Merge main into #2620; clean merge, no conflicts

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

.github/workflows/windows-arm64.yml

@@ -29,7 +29,7 @@ permissions:
 jobs:
   windows-arm64:
     # Immutable supporting workflow revision until the new install contract lands upstream.
-    uses: storytold/craft-common-actions/.github/workflows/windows-arm64.yml@8bb4e5ab95443171104ad88113fe1ef9b0e5ce3f
+    uses: storytold/craft-common-actions/.github/workflows/windows-arm64.yml@fa5ef18780cf5e7d5d3b8de068de56cffc83cac5
     with:
       app-name: effectcraft
       app-dir: EffectCraft

CONTRIBUTING.md

@@ -7,12 +7,36 @@ work apply to everyone, people and AI agents alike, and they are not negotiable.
 
 You need [Rust](https://rustup.rs/) 1.95 or newer.
 
+On Linux the desktop app plays preview sound through `cpal`, so the build needs a usable ALSA
+pkg-config package: an `alsa.pc` that pkg-config can find, naming the linkable ALSA runtime
+library (usually `libasound.so.2`). `alsa-sys` runs pkg-config at build time; it does not compile
+ALSA's headers. Without a usable package the build fails at link time with an unrelated-looking
+error; `cargo xtask ci` probes pkg-config up front and names the package:
+
+```sh
+sudo dnf install alsa-lib-devel        # Fedora
+sudo apt install libasound2-dev        # Debian / Ubuntu
+sudo pacman -S alsa-lib                # Arch
+```
+
+If you cannot install the package, point `PKG_CONFIG_PATH` at a directory holding an `alsa.pc`
+whose `Libs` line names your system's `libasound` (usually `libasound.so.2`); every CI run needs
+that variable set.
+
 ```sh
 cargo run -p effectcraft -- --demo       # the desktop app, with the demo project
 cargo test --workspace
 cargo xtask ci                           # what every commit must pass
 ```
 
+The default `dev` profile keeps debug info to line tables: builds are fast and panics/backtraces
+still name the file and line, but a debugger cannot show local variables. For an interactive
+debugger session use the `dev-full` profile, which is the same build with full debug info:
+
+```sh
+cargo run --profile dev-full -p effectcraft -- --demo
+```
+
 ## Ground rules
 
 - **Clean room.** Work from After Effects' public documentation and its observable behaviour only.

Cargo.lock

@@ -1623,6 +1623,7 @@ name = "effectcraft-media"
 version = "0.18.0"
 dependencies = [
  "craft-docpath",
+ "effectcraft-color",
  "effectcraft-model",
  "effectcraft-pdf",
  "effectcraft-project",
@@ -7199,6 +7200,7 @@ name = "xtask"
 version = "0.18.0"
 dependencies = [
  "chrono",
+ "pkg-config",
  "serde_json",
  "tempfile",
 ]

Cargo.toml

@@ -153,6 +153,13 @@ opt-level = 1
 # Panics and backtraces keep file and line; full debug info only made the many test binaries large.
 debug = "line-tables-only"
 
+# Same settings as `dev`, but with full debug info for interactive debugger sessions: local
+# variables, parameters and column breakpoints work. Use `--profile dev-full` when debugging;
+# everything else stays on the fast default. See CONTRIBUTING.md, "Setup".
+[profile.dev-full]
+inherits = "dev"
+debug = true
+
 # Pixel hot loops: keep debug builds interactive.
 [profile.dev.package.effectcraft-raster]
 opt-level = 3

README.md

@@ -20,7 +20,7 @@
 
 <p align="center">
   A free, open-source compositor: compositions, layers,
-  keyframes, 306 effects, layer styles, expressions, 3D cameras and lights, and a render queue, native on macOS,
+  keyframes, 308 effects, layer styles, expressions, 3D cameras and lights, and a render queue, native on macOS,
   Windows and Linux, and in the browser. Young, moving fast, and already usable.
 </p>
 
@@ -84,9 +84,10 @@ a few places where it matters to us:
   without a plugin.
 - **A project file you can read.** Projects are versioned JSON (`.ecproj`), so they diff cleanly
   in version control.
-- **Everything is scriptable.** Every menu item, timeline drag and property edit goes through one
-  command registry, so the same actions are reachable from a command line, a JSON control
-  channel and an MCP server for agents.
+- **Everything is scriptable.** Menu actions, timeline edits and property changes are exposed as
+  commands. Engine commands are available through the CLI, JSON control channel and MCP;
+  UI-only commands use the frontend dispatcher and can be invoked through the control channel
+  or an attached MCP bridge.
 - **No FFmpeg.** Video and audio decoding and encoding are pure Rust: FilmCraft's codecs and
   EffectCraft's own VP9, AV1, HEVC and Opus encoders.
 
@@ -126,7 +127,7 @@ or into the Timeline, between layers and at the time you point to.
 
 ## Effects
 
-306 built-in effects across its categories, each with its parameter names, order and
+308 built-in effects across its categories, each with its parameter names, order and
 defaults: blur and sharpen, channel, color correction (Curves, Levels, Hue/Saturation, a full
 color-grading panel…), distort (Warp, Bulge, Turbulent Displace, CC Power Pin…), generate (Fractal Noise,
 Gradient Ramp, Stroke, Write-on, Audio Spectrum…), keying, matte, noise and grain, perspective,
@@ -173,8 +174,10 @@ cannot express; File ▸ Import ▸ Lottie… opens one as a new composition.
 
 ## Built for agents
 
-Everything you can do from a menu is a command with an id, and agents can reach every one of
-them:
+Engine commands are available through the CLI, JSON control channel and MCP. UI-only commands
+need the running app's frontend dispatcher: complete menu access requires the app's control
+channel or an attached MCP bridge. Headless MCP sessions expose supported engine commands,
+but not UI-only commands or bridge-only `ui_*` tools.
 
 - **MCP server:** `effectcraft-cli mcp` speaks the Model Context Protocol over stdio, headless
   or bridged to the running app (`--bridge 9877`). Tools cover commands, the project and property
@@ -228,7 +231,7 @@ tests, layering, asset attribution and the WebAssembly build). See [CONTRIBUTING
 ## Where it stands
 
 EffectCraft is young: its first commit was on 1 October 2026. A comprehensive feature set
-exists, including 306 effects, but breadth is not the same as full maturity across every edge
+exists, including 308 effects, but breadth is not the same as full maturity across every edge
 case. Today it's a good place to try things and to tell us what breaks. It isn't yet recommended
 for production client work. In particular:
 

ROADMAP.md

@@ -2,7 +2,7 @@
 
 **Stage: alpha** · next: beta, ~30 points of "ready for real work" and ~350–620 h away
 
-> **Last reviewed:** 2026-10-12 · **Last updated:** 2026-10-12 · **Change:** minor (open-issue count, crash list and localization share re-audited against `upstream/main` 470ea7a3) · **Target:** Adobe After Effects 2026 (26.5.0.89)
+> **Last reviewed:** 2026-10-22 · **Last updated:** 2026-10-30 · **Change:** minor (localization: 303 more panel/dialog rows in Japanese and the Chinese catalogs; recounted after #1774: Japanese 27% → 46%, Simplified Chinese 29% → 46%, Traditional Chinese 29% → 38%, overall 18% → 24%) · **Target:** Adobe After Effects 2026 (26.5.0.89)
 
 EffectCraft aims to do what After Effects does, with the same panels, menus and behaviour, written
 from scratch in Rust. This page is the one-page summary; the evidence is in
@@ -51,7 +51,7 @@ Linux/Windows reliability (30–50 h) and depth in animation, masks, effects and
 | UI/UX fidelity | 65% | 60–120 | [ui-parity.md](docs/ui-parity.md) |
 | File formats | 50% | 130–230 | [file-format-parity.md](docs/file-format-parity.md) |
 | Hardware | 40% | 60–120 | [hardware-parity.md](docs/hardware-parity.md) |
-| Localization | 18% | 60–110 + review | [localization-parity.md](docs/localization-parity.md) |
+| Localization | 24% | 60–110 + review | [localization-parity.md](docs/localization-parity.md) |
 | Performance | 35% | 50–100 | [gaps.md](docs/gaps.md#g5-performance-at-real-world-scale) |
 | Stability | 45% | 40–80 | [gaps.md](docs/gaps.md#g3-stability-and-a-green-main) |
 | Platforms | 65% | 30–60 | [gaps.md](docs/gaps.md#g2-real-user-reliability-on-every-platform) |
@@ -80,24 +80,24 @@ Weights and evidence per row: [target-app-parity.md](docs/target-app-parity.md#b
 
 ## Languages
 
-UI strings translated out of ≈ 3,900 (detail: [localization-parity.md](docs/localization-parity.md)).
+UI strings translated out of ≈ 4,200 (detail: [localization-parity.md](docs/localization-parity.md)).
 
 | Language | Status | % |
 |---|---|---:|
 | English | full | 100% |
-| Simplified Chinese | partial (menus, part of the panels) | 29% |
-| Spanish | menus only | 16% |
+| Simplified Chinese | partial (menus, most of the panels) | 46% |
+| Spanish | menus only | 29% |
 | Hindi | none | 0% |
 | Arabic | none | 0% |
 | French | menus only | 16% |
-| Portuguese (Brazil) | partial (menus, part of the panels) | 26% |
+| Portuguese (Brazil) | partial (menus, part of the panels) | 34% |
 | Indonesian | none | 0% |
-| Japanese | partial (menus, part of the panels) | 27% |
+| Japanese | partial (menus, most of the panels) | 46% |
 | German | menus only | 16% |
 | Korean | none | 0% |
 | Vietnamese | none | 0% |
 
-Also shipped: Traditional Chinese (partial, 29%), Ukrainian (partial, 29%), Czech (partial, 29%), Georgian (partial, 38%; native-speaker reviewed) and Russian (menus only, 16%). No other language has had
+Also shipped: Traditional Chinese (partial, 38%), Ukrainian (partial, 29%), Czech (partial, 29%), Polish (partial, 34%), Georgian (partial, 39%; native-speaker reviewed) and Russian (menus only, 15%). No other language has had
 native-speaker review.
 
 ## Upcoming
@@ -120,10 +120,22 @@ Come tell us what matters most to you on [Discord](https://discord.gg/artcraft).
 - 2026-10-28: A shape layer's Rectangle and Ellipse Size get the Constrain Proportions chain
   that Scale has, so a circle stays a circle while its size is typed, scrubbed or keyed; it
   starts off, so existing shapes behave as before (#2489).
+- 2026-10-24: Shape layers have the Wiggle Transform path operation (Contents ▸ Add, or
+  `layer.addShapeItem {kind: "wiggler"}`): it wiggles the anchor point, position, scale and
+  rotation of the paths above it by random amounts that change over time, up to the Transform
+  values it holds. The copies of a Repeater above it wiggle independently as far as its
+  Correlation allows; with the Repeater below it, they wiggle together.
+- 2026-10-22: Localization: the panel/dialog catalogs gain 303 rows in Japanese, Simplified
+  Chinese and Traditional Chinese — panel tabs, form and dialog labels, panel context menus,
+  tracker/graph/text-panel controls, File-panel footers and credits. Recounted after #1774:
+  Japanese is 1,923 of ≈ 4,200 interface strings (46%, with 297 effect names); the Chinese
+  panel catalogs hold 998 (Simplified) and 951 (Traditional) rows, and Simplified Chinese is
+  46% with its 307 effect names; the overall share is ≈ 24%.
 - 2026-10-16: Convert To Bezier Path turns a shape layer's Rectangle, Ellipse or Polystar
   path into an editable Path 1 with the same geometry, as After Effects does; it used to
   apply to mask RotoBezier only, so a parametric shape path could not be converted at all
   and its vertices could not be edited or animated (#932).
+- 2026-10-14: Georgian (`ka`): every menu row, every panel-catalog row the Chinese catalogs have plus 195 Georgian-only ones, and the effect names and categories; Match System for `ka` / `ka-GE` / `ka_GE.UTF-8` locales. Reviewed by a native speaker.
 - 2026-10-12: Roto Brush span edits report strokes outside a trimmed layer without panicking;
   strokes and undo history are preserved so restoring the timing allows the span edit again.
 - 2026-10-11: Ukrainian panels caught up with the Chinese catalogs. The 95 rows the panel
@@ -138,7 +150,6 @@ Come tell us what matters most to you on [Discord](https://discord.gg/artcraft).
   follow the shared standard: `docs/parity.md` became `docs/target-app-parity.md`; new
   `docs/roadmap.md`, `localization-parity.md`, `file-format-parity.md`, `hardware-parity.md`,
   `ui-parity.md`, `effects-parity.md` and `scripting-parity.md`.
-- 2026-10-14: Georgian (`ka`): every menu row, every panel-catalog row the Chinese catalogs have plus 195 Georgian-only ones, and the effect names and categories; Match System for `ka` / `ka-GE` / `ka_GE.UTF-8` locales. Reviewed by a native speaker.
 - 2026-10-10: Spanish (#460) and Brazilian Portuguese (#217) menu translations.
 - 2026-10-10: Japanese now translates the interface below the menu bar too: `crates/ui-egui/src/i18n/ui.rs` has a Japanese table with the same 396 rows as the Chinese ones (panels, dialogs, buttons and tooltips; the shape test keeps the three catalogs listing the same source strings). Menus were already Japanese.
 - 2026-10-09: Ukrainian now covers all 396 current panel-catalog strings, including dialogs, buttons and tooltips, alongside its menu translation. The catalog keeps the same source keys and placeholder counts as the Chinese catalogs; missing or engine-generated text still falls back to English.
@@ -158,11 +169,12 @@ Come tell us what matters most to you on [Discord](https://discord.gg/artcraft).
 
 | Date | Change | Summary |
 |---|---|---|
+| 2026-10-22 | minor | Localization: 300 more panel/dialog rows in Japanese and the Chinese catalogs, plus the review's three missing rows (Basic, Advanced, Play/Stop) — panel tabs, form and dialog labels, context menus, tracker/graph/text-panel controls, File-panel footers, credits; language shares recounted after #1774 (Japanese 27% → 46% with 297 effect names, Simplified Chinese 29% → 46% with 307 effect names, Traditional Chinese 29% → 38%, overall 18% → 24%) |
 | 2026-10-12 | minor | Open-issue count (134 to 216), crash list and localization share (12% to 18%) updated to match docs/gaps.md |
 | 2026-10-12 | patch | Roto Brush span validation after trimming; command regressions for both layer edges |
+| 2026-10-12 | minor | Shared PDF object/xref parsing with bounded app-owned conversion and preserved stream budgets; drawing, EPS and image/font policy remain unchanged |
 | 2026-10-10 | minor | Hours to ≈ 95% for each audience |
 | 2026-10-10 | minor | Headline adds mainstream practitioner (≈ 47%) and essentials user (≈ 52%) |
-| 2026-10-12 | minor | Shared PDF object/xref parsing with bounded app-owned conversion and preserved stream budgets; drawing, EPS and image/font policy remain unchanged |
-| 2026-10-10 | minor | Stage checked against the new core-workflow gate (all six pass; still alpha) |
 | 2026-10-10 | major | Rewritten to the shared progress-docs standard: stage, two numbers, dimensions, features, languages, upcoming, progress log; milestones moved to docs/roadmap.md |
+| 2026-10-10 | minor | Stage checked against the new core-workflow gate (all six pass; still alpha) |
 | 2026-10-05 | major | Two numbers (breadth vs real use) and workstreams G1–G9 |

apps/effectcraft-cli/src/main.rs

@@ -1296,7 +1296,7 @@ fn adv3d_bench_comp(p: &mut effectcraft_engine::project::Project) -> Option<Item
         set(l, "cameraOptions/highlightGain", Value::Scalar(20.0));
         set(l, "cameraOptions/highlightThreshold", Value::Scalar(200.0));
     });
-    comp.layers = layers;
+    comp.layers = layers.into();
     Some(p.add_item("Advanced 3D (bench)", effectcraft_engine::color::Label::None, None, ItemKind::Comp(comp.into())))
 }
 

apps/effectcraft-web/Cargo.toml

@@ -37,6 +37,8 @@ js-sys = "0.3"
 web-sys = { version = "0.3", features = [
     "Blob",
     "BlobPropertyBag",
+    "AbortController",
+    "AbortSignal",
     "CssStyleDeclaration",
     "Document",
     "Element",
@@ -51,6 +53,12 @@ web-sys = { version = "0.3", features = [
     "HtmlInputElement",
     "Location",
     "Navigator",
+    "ReadableStream",
+    "ReadableStreamDefaultReader",
+    "Request",
+    "RequestCache",
+    "RequestInit",
+    "Response",
     "Url",
     "UrlSearchParams",
     "Window",

apps/effectcraft-web/src/app.rs

@@ -6,7 +6,8 @@ use std::sync::atomic::{AtomicBool, Ordering};
 
 use effectcraft_engine::Session;
 
-use crate::{api, audio, browse, diskcache, files, frames, persist, storage, worker};
+use crate::startup::Startup;
+use crate::{api, audio, browse, config_file, diskcache, files, frames, persist, storage, worker};
 use effectcraft_ui_egui::EffectcraftApp;
 use serde_json::json;
 use wasm_bindgen::prelude::*;
@@ -83,8 +84,12 @@ pub(crate) fn open_or_import(app: &mut EffectcraftApp, paths: Vec<String>) {
 /// The eframe app: the shared EffectCraft UI plus the browser host's per-frame duties.
 pub struct WebApp {
     pub app: EffectcraftApp,
-    /// Keep the session snapshot (off with `?empty`).
+    /// Keep the session snapshot (off with `?empty`; off with an explicit `"demo"` startup until
+    /// the user's own work begins, see `demo_start`).
     pub persist: bool,
+    /// Started on the demo by the config: the snapshot stays off, so the demo never replaces the
+    /// last visit's project, until the user opens a project from a file or edits the demo.
+    pub demo_start: bool,
 }
 
 impl eframe::App for WebApp {
@@ -117,6 +122,11 @@ impl eframe::App for WebApp {
         api::poll_replies();
         // Render Queue outputs written this frame (here or by a worker) → downloads.
         files::flush_downloads();
+        // The user's own work after a demo start is worth keeping too: turn the snapshot on.
+        if self.demo_start && (self.app.session.path.is_some() || self.app.session.is_dirty()) {
+            self.demo_start = false;
+            self.persist = true;
+        }
         // What a reload comes back to.
         if self.persist {
             // The app's monotonic clock: `ctx.input(|i| i.time)` is stale in a logic-only tick.
@@ -223,6 +233,11 @@ pub async fn start(canvas_id: String) -> Result<(), JsValue> {
     };
     api::set_info("storage", json!({"backend": persist::backend(), "entries": stored, "loadMs": t0.elapsed().as_secs_f64() * 1000.0}));
     audio::install_unlock();
+    // `./effectcraft-config.json`: what to open on load.
+    // `?empty` and `?demo` decide by themselves, so they skip the request.
+    let startup = if empty || query_flag("demo") { Startup::default() } else { config_file::startup().await };
+    // An explicit `"demo"` start leaves the saved session alone until the user opens or edits something.
+    let keep_session = !empty && startup.keeps_session();
     browse::restore();
     diskcache::init();
     storage::refresh();
@@ -248,7 +263,7 @@ pub async fn start(canvas_id: String) -> Result<(), JsValue> {
                     // The canvas can't present any more (#225): the page says so over it and
                     // offers a reload, which brings the session back when browser storage keeps it.
                     let lost = gpu_failures.clone();
-                    let kept = !empty && persist::backend() != "memory";
+                    let kept = keep_session && persist::backend() != "memory";
                     rs.device.set_device_lost_callback(move |reason, message| {
                         let message = format!("GPU device lost ({reason:?}): {message}");
                         lost.report(&message, true);
@@ -257,11 +272,14 @@ pub async fn start(canvas_id: String) -> Result<(), JsValue> {
                 }
                 let mut session = session();
                 session.load_settings();
+                // Scripts in Scripts/Startup run before a project opens.
+                let _ = session.execute("file.runStartupScripts", json!({}));
                 let recovery = session.begin_recovery();
-                // `?empty`: a blank project; `?demo`: the demo project; otherwise the last visit's
-                // project (the demo on a first visit).
-                let restored = !empty && !query_flag("demo") && persist::restore(&mut session);
-                if !restored && !empty {
+                // `?empty`: a blank project; `?demo`: the demo project; otherwise what the config's
+                // `startup` says (default: the last visit's project, the demo on a first visit).
+                let demo = query_flag("demo");
+                let restored = !empty && !demo && startup.restores() && persist::restore(&mut session);
+                if !restored && !empty && (demo || startup.demo_when_nothing_restored()) {
                     let _ = session.execute("file.openDemoProject", json!({}));
                 }
                 api::set_info("restored", json!(restored));
@@ -287,7 +305,7 @@ pub async fn start(canvas_id: String) -> Result<(), JsValue> {
                 app = app.with_control(rx);
                 let backend = cc.wgpu_render_state.as_ref().map(|rs| format!("{:?}", rs.adapter.get_info().backend));
                 api::set_info("backend", json!(backend));
-                Ok(Box::new(WebApp { app, persist: !empty }))
+                Ok(Box::new(WebApp { app, persist: keep_session, demo_start: !empty && !keep_session }))
             }),
         )
         .await?;

apps/effectcraft-web/src/config_file.rs

@@ -0,0 +1,73 @@
+//! `./effectcraft-config.json`, fetched once per page load and shared by whoever reads a key.
+
+use std::cell::RefCell;
+
+use wasm_bindgen::{JsCast, closure::Closure};
+use wasm_bindgen_futures::JsFuture;
+
+use crate::startup::{self, Startup};
+
+/// Longest the request and the body read may take (ms); a stalled server must not hold up start-up.
+const TIMEOUT_MS: i32 = 5_000;
+
+thread_local! {
+    /// `None`: not fetched yet; `Some(None)`: no usable file.
+    static FILE: RefCell<Option<Option<Vec<u8>>>> = const { RefCell::new(None) };
+}
+
+/// The config file's bytes, or `None` when it is missing, too large, unreadable or the request
+/// takes longer than [`TIMEOUT_MS`] (the timer aborts the request and covers the body read).
+async fn fetch() -> Option<Vec<u8>> {
+    let win = web_sys::window()?;
+    let ctl = web_sys::AbortController::new().ok()?;
+    let init = web_sys::RequestInit::new();
+    // Always ask the server: the file is the operator's switch, never a cached copy.
+    init.set_cache(web_sys::RequestCache::NoCache);
+    init.set_signal(Some(&ctl.signal()));
+    let on_timeout = Closure::once(move || ctl.abort());
+    let timer = win.set_timeout_with_callback_and_timeout_and_arguments_0(on_timeout.as_ref().unchecked_ref(), TIMEOUT_MS).ok()?;
+    let out = read(&win, &init).await;
+    win.clear_timeout_with_handle(timer);
+    out
+}
+
+/// Fetch the file and read its body chunk by chunk, giving up as soon as it passes `CONFIG_MAX`.
+async fn read(win: &web_sys::Window, init: &web_sys::RequestInit) -> Option<Vec<u8>> {
+    let req = web_sys::Request::new_with_str_and_init("effectcraft-config.json", init).ok()?;
+    let resp: web_sys::Response = JsFuture::from(win.fetch_with_request(&req)).await.ok()?.dyn_into().ok()?;
+    if resp.status() != 200 {
+        return None;
+    }
+    let reader: web_sys::ReadableStreamDefaultReader = resp.body()?.get_reader().unchecked_into();
+    let mut out = Vec::new();
+    loop {
+        let chunk = JsFuture::from(reader.read()).await.ok()?;
+        if js_sys::Reflect::get(&chunk, &"done".into()).ok()?.as_bool() == Some(true) {
+            return Some(out);
+        }
+        let bytes: js_sys::Uint8Array = js_sys::Reflect::get(&chunk, &"value".into()).ok()?.dyn_into().ok()?;
+        if out.len().saturating_add(bytes.length() as usize) > startup::CONFIG_MAX {
+            // Stop the download: the limit is enforced while reading, not after the whole body arrived.
+            let _ = reader.cancel();
+            return None;
+        }
+        out.extend_from_slice(&bytes.to_vec());
+    }
+}
+
+/// The config file's bytes (`None` when there is none), fetched on the first call.
+pub async fn bytes() -> Option<Vec<u8>> {
+    if let Some(done) = FILE.with(|f| f.borrow().clone()) {
+        return done;
+    }
+    let got = fetch().await;
+    FILE.with(|f| *f.borrow_mut() = Some(got.clone()));
+    got
+}
+
+/// The configured startup behaviour.
+pub async fn startup() -> Startup {
+    let s = bytes().await.map(|b| startup::parse(&b)).unwrap_or_default();
+    log::info!("startup: {s:?}");
+    s
+}

apps/effectcraft-web/src/lib.rs

@@ -18,10 +18,11 @@
 //! | cpal audio output | Web Audio: an AudioWorklet fed from the preview mixdown (`audio`) |
 //! | TCP control channel / MCP | `window.effectcraft` JavaScript API (`api`) |
 //!
-//! [`store`] is portable (unit-tested natively); everything else is `wasm32`-only.
+//! [`store`] and [`startup`] are portable (unit-tested natively); everything else is `wasm32`-only.
 
 #![deny(clippy::unwrap_used, clippy::expect_used, clippy::panic, clippy::unimplemented, clippy::todo, clippy::unreachable)]
 
+pub mod startup;
 pub mod store;
 
 #[cfg(target_arch = "wasm32")]
@@ -33,6 +34,8 @@ pub mod audio;
 #[cfg(target_arch = "wasm32")]
 pub mod browse;
 #[cfg(target_arch = "wasm32")]
+pub mod config_file;
+#[cfg(target_arch = "wasm32")]
 pub mod diskcache;
 #[cfg(target_arch = "wasm32")]
 pub mod files;

apps/effectcraft-web/src/startup.rs

@@ -0,0 +1,55 @@
+//! The `startup` key of `./effectcraft-config.json`: which project the page opens on load.
+//!
+//! | Value | On load |
+//! |---|---|
+//! | `"last"` (and absent) | the last visit's project; the demo project on a first visit |
+//! | `"empty"` | the last visit's project; a blank project on a first visit, never the demo |
+//! | `"demo"` | the demo project, whatever the last visit left |
+//!
+//! The `?empty` and `?demo` URL flags still win. Anything else (a missing key, another type, an
+//! unknown value, a config that is not JSON) is the default, `"last"`.
+
+use serde_json::Value;
+
+/// What the page opens on load.
+#[derive(Clone, Copy, Debug, Default, PartialEq, Eq)]
+pub enum Startup {
+    #[default]
+    Last,
+    Empty,
+    Demo,
+}
+
+/// The largest config file read (bytes).
+pub const CONFIG_MAX: usize = 64 * 1024;
+
+/// The `startup` key of a config file's bytes.
+pub fn parse(bytes: &[u8]) -> Startup {
+    if bytes.len() > CONFIG_MAX {
+        return Startup::default();
+    }
+    let Ok(v) = serde_json::from_slice::<Value>(bytes) else { return Startup::default() };
+    match v.get("startup").and_then(Value::as_str) {
+        Some("empty") => Startup::Empty,
+        Some("demo") => Startup::Demo,
+        _ => Startup::Last,
+    }
+}
+
+impl Startup {
+    /// Whether the last visit's project is restored (off for the demo).
+    pub fn restores(self) -> bool {
+        self != Startup::Demo
+    }
+
+    /// Whether the session snapshot keeps being saved (off for the demo, so it never replaces the
+    /// project the last visit left).
+    pub fn keeps_session(self) -> bool {
+        self != Startup::Demo
+    }
+
+    /// Whether the demo project opens when nothing was restored (off for a blank start).
+    pub fn demo_when_nothing_restored(self) -> bool {
+        self != Startup::Empty
+    }
+}

apps/effectcraft-web/tests/it/main.rs

@@ -0,0 +1 @@
+mod startup_tests;

apps/effectcraft-web/tests/it/startup_tests.rs

@@ -0,0 +1,52 @@
+//! The `startup` key of the config file.
+
+use effectcraft_web::startup::{CONFIG_MAX, Startup, parse};
+
+/// The three accepted values parse.
+#[test]
+fn the_three_values() {
+    assert_eq!(parse(br#"{"startup":"empty"}"#), Startup::Empty);
+    assert_eq!(parse(br#"{"startup":"demo"}"#), Startup::Demo);
+    assert_eq!(parse(br#"{"startup":"last"}"#), Startup::Last);
+}
+
+/// A missing key, a wrong type, an unknown value or a non-object file gives `Last`.
+#[test]
+fn absent_or_invalid_is_the_default() {
+    for bytes in
+        [&b"{}"[..], b"", b"not json", b"[]", b"null", br#"{"startup":1}"#, br#"{"startup":"Empty"}"#, br#"{"startup":null}"#, br#"{"startup":["empty"]}"#]
+    {
+        assert_eq!(parse(bytes), Startup::Last, "{:?}", String::from_utf8_lossy(bytes));
+    }
+}
+
+/// Other keys do not hide `startup`.
+#[test]
+fn a_config_with_other_keys_still_has_its_startup() {
+    assert_eq!(parse(br#"{"remote":{"mounts":[]},"startup":"empty"}"#), Startup::Empty);
+    assert_eq!(parse(br#"{"startup":"demo","unknown":{"a":1}}"#), Startup::Demo);
+}
+
+/// A file over `CONFIG_MAX` is ignored.
+#[test]
+fn an_oversized_file_is_the_default() {
+    let mut big = br#"{"startup":"empty","pad":""#.to_vec();
+    big.extend(std::iter::repeat_n(b'x', CONFIG_MAX));
+    big.extend_from_slice(br#""}"#);
+    assert_eq!(parse(&big), Startup::Last);
+}
+
+/// Which project each value restores or opens.
+#[test]
+fn what_each_value_does_on_load() {
+    assert!(Startup::Last.restores() && Startup::Last.demo_when_nothing_restored());
+    assert!(Startup::Empty.restores() && !Startup::Empty.demo_when_nothing_restored());
+    assert!(!Startup::Demo.restores() && Startup::Demo.demo_when_nothing_restored());
+}
+
+/// Only the explicit demo start stops saving the session.
+#[test]
+fn only_the_demo_start_leaves_the_saved_session_alone() {
+    assert!(Startup::Last.keeps_session() && Startup::Empty.keeps_session());
+    assert!(!Startup::Demo.keeps_session());
+}

apps/effectcraft-web/web/sw.js

@@ -3,7 +3,8 @@
 // `cargo xtask web` fills in the build's file list and version. Every file is precached into a
 // cache named after the version, served cache-first (responses keep the server's headers, so
 // the page stays cross-origin isolated: COOP/COEP), and old versions are dropped once the new
-// one activates. Anything else same-origin is fetched from the network and cached for next time.
+// one activates. Anything else same-origin is fetched from the network and cached for next time,
+// except the config file, which must stay live.
 const VERSION = "__EC_VERSION__";
 const FILES = __EC_FILES__;
 const CACHE = `effectcraft-${VERSION}`;
@@ -30,6 +31,7 @@ self.addEventListener("fetch", (event) => {
   const req = event.request;
   const url = new URL(req.url);
   if (req.method !== "GET" || url.origin !== self.location.origin) return;
+  if (url.pathname.endsWith("/effectcraft-config.json")) return;
   event.respondWith(
     (async () => {
       const cache = await caches.open(CACHE).catch(() => null);

apps/effectcraft/src/main.rs

@@ -263,6 +263,9 @@ fn main() -> eframe::Result {
             // Fit the window to its monitor, or put it back where it was (still hidden).
             let saved_window = session.config.as_deref().and_then(window::load);
             let opened = cc.winit_window().map(|w| window::restore(w, saved_window));
+            // Scripts in Scripts/Startup run before a project opens (a failing one is reported in
+            // a toast).
+            let _ = session.execute("file.runStartupScripts", json!({}));
             let recovery = if control_port.is_none() { session.begin_recovery() } else { None };
             let project = files.iter().find(|f| is_project_file(f)).cloned();
             if let Some(p) = project {
@@ -495,6 +498,8 @@ impl eframe::App for Desktop {
         self.launch.exited();
         self.window.save(self.app.session.config.as_deref());
         self.app.on_exit();
+        // Scripts in Scripts/Shutdown run with the project closed.
+        let _ = self.app.session.execute("file.runShutdownScripts", json!({}));
     }
 
     fn raw_input_hook(&mut self, ctx: &egui::Context, raw_input: &mut egui::RawInput) {

contributors/people.toml

@@ -22,6 +22,11 @@ real_name = "Brandon Thomas"
 display_name = "Brandon Thomas"
 sync_github_name = false
 
+[people.lewandowskit]
+real_name = "Tomasz Lewandowski"
+display_name = "Tomasz Lewandowski"
+sync_github_name = false
+
 [people.switch87]
 real_name = "Gert Pellin"
 display_name = "Gert Pellin"

crates/automation/src/confine.rs

@@ -30,10 +30,9 @@ pub struct Confinement {
     write: Vec<PathBuf>,
 }
 
-/// Commands that run code, act outside the project or open other applications.
+/// Commands that run code, act outside the project or open other applications, besides the
+/// commands that run scripts ([`effectcraft_engine::commands::scripts::RUNS_SCRIPTS`]).
 const REFUSED: &[&str] = &[
-    "script.run",
-    "file.runScript",
     "file.installScript",
     "file.installScriptUIPanel",
     "file.uninstallScript",
@@ -167,7 +166,7 @@ impl Confinement {
     /// Check engine command `id` with `params` before it runs. Returns what must still be looked
     /// up and passed to [`Confinement::check_lookup`] for commands that write implicitly.
     pub fn check_command(&self, id: &str, params: &Value) -> Result<Option<Lookup>> {
-        if REFUSED.contains(&id) {
+        if REFUSED.contains(&id) || effectcraft_engine::commands::scripts::RUNS_SCRIPTS.contains(&id) {
             return Err(Error::BadArgs(format!("`{id}` is not available while file access is confined (--automation-read-root/--automation-write-root)")));
         }
         // Scripts can't grant themselves the access the user withheld
@@ -397,6 +396,7 @@ mod tests {
             let classified = keys_of(READS, id).is_some()
                 || keys_of(WRITES, id).is_some()
                 || REFUSED.contains(&id)
+                || effectcraft_engine::commands::scripts::RUNS_SCRIPTS.contains(&id)
                 || IMPLICIT_WRITES.contains(&id)
                 || id.starts_with("renderQueue.")
                 || id == "render.addOutputModule"

crates/automation/src/tests.rs

@@ -1412,6 +1412,18 @@ fn automation_roots_confine_file_access() {
     // Scripts can read and write anything: refused.
     denied(&mut s, "run_script", json!({"code": "1 + 1"}));
     denied(&mut s, "execute_command", json!({"command": "file.runScript", "params": {"path": p(&read, "x.jsx")}}));
+    for (id, params) in [
+        ("file.runStartupScripts", json!({})),
+        ("file.runShutdownScripts", json!({})),
+        // ScriptUI panels run their script when they open.
+        ("window.scriptPanel", json!({"name": "Layer Tools.jsx"})),
+        ("window.restoreScriptPanels", json!({})),
+    ] {
+        let msg = denied(&mut s, "execute_command", json!({"command": id, "params": params}));
+        assert!(msg.contains("not available while file access is confined"), "{id}: {msg}");
+        let msg = denied(&mut s, "batch", json!({"steps": [{"command": id, "params": params}]}));
+        assert!(msg.contains("not available while file access is confined"), "{id}: {msg}");
+    }
     // Writes to the files the agent named: none outside.
     assert_eq!(std::fs::read_dir(&outside).unwrap().count(), 1, "only the unconfined save");
     let _ = std::fs::remove_dir_all(&base);

crates/automation/tests/qa/compositing.rs

@@ -35,7 +35,7 @@ fn import_footage(qa: &mut Qa) -> (Value, Value) {
     // Footage: the sequence, and a layered PSD written by the app itself (Save Frame As ▸
     // Photoshop Layers) from a small comp.
     let seq = write_sequence(qa);
-    let imp = qa.exec("file.import", json!({"paths": [seq]}));
+    let imp = qa.exec("file.import", json!({"paths": [seq], "sequence": true}));
     let seq_item = imp["items"][0].clone();
     let project = qa.tool("get_project", json!({}));
     let it = project["items"].as_array().unwrap().iter().find(|i| i["id"] == seq_item).unwrap().clone();

crates/automation/tests/qa/tracking.rs

@@ -52,7 +52,7 @@ fn shake_offset(f: u32) -> (i64, i64) {
 
 /// Import a sequence at 12 fps and make a comp of it; returns (comp, layer).
 fn plate_comp(qa: &mut Qa, first: &str, name: &str) -> (Value, Value) {
-    let item = qa.exec("file.import", json!({"paths": [first]}))["items"][0].clone();
+    let item = qa.exec("file.import", json!({"paths": [first], "sequence": true}))["items"][0].clone();
     qa.exec("file.interpretFootage", json!({"items": [item.clone()], "frameRate": 12}));
     let comp = qa.exec("comp.new", json!({"name": name, "width": 160, "height": 90, "frameRate": 12, "duration": 1}))["comp"].clone();
     let layer = qa.exec("layer.addItem", json!({"item": item}))["layer"].clone();

crates/av1enc/src/decide.rs

@@ -174,6 +174,8 @@ pub(crate) struct Decider<'a> {
     ac_q: f32,
     dc_qi: i64,
     ac_qi: i64,
+    /// Smallest magnitude that quantises to a non-zero level, `[dc, ac][intra]`.
+    dead_zone: [[f32; 2]; 2],
     lambda: f64,
     lambda_sad: f64,
     /// Half-sample interpolations of the reference luma (visible area): (8, 0), (0, 8), (8, 8).
@@ -183,6 +185,9 @@ pub(crate) struct Decider<'a> {
 }
 
 const MODE_BITS_INTRA: f64 = 3.0;
+/// Dead-zone quantiser rounding offsets (below one half) for inter and intra blocks.
+const INTER_RND: f32 = 0.30;
+const INTRA_RND: f32 = 0.38;
 
 impl<'a> Decider<'a> {
     pub fn new(g: &'a FrameGeom, bd: u32, qidx: u8, intra_only: bool, src: &'a [Plane; 3], refr: Option<&'a RefFrame>) -> Self {
@@ -209,6 +214,7 @@ impl<'a> Decider<'a> {
             ac_q: ac_qi as f32,
             dc_qi,
             ac_qi,
+            dead_zone: [dc_qi, ac_qi].map(|q| [INTER_RND, INTRA_RND].map(|rnd| zero_threshold(q as f32, rnd))),
             lambda,
             lambda_sad: lambda.sqrt(),
             half: match refr {
@@ -577,8 +583,9 @@ impl<'a> Decider<'a> {
             let (dy, dx) = (m[0] >> 3, m[1] >> 3);
             dx >= lim_x.0 && dx <= lim_x.1 && dy >= lim_y.0 && dy <= lim_y.1
         };
+        let lg = log2_table();
         let mv_bits = |m: [i32; 2]| -> f64 {
-            let comp = |d: i32| if d == 0 { 0.5 } else { 2.0 + 2.0 * ((d.abs() / 8) as f64 + 1.0).log2() };
+            let comp = |d: i32| if d == 0 { 0.5 } else { 2.0 + 2.0 * log2_of(lg, (d.abs() / 8) as usize + 1) };
             comp(m[0] - pred_mv[0]) + comp(m[1] - pred_mv[1])
         };
         let cost =
@@ -863,12 +870,18 @@ impl<'a> Decider<'a> {
         }
         forward_2d(res, coef, n, tx_type);
         // dead-zone quantiser: rounding offset below one half
-        let rnd = if intra { 0.38f32 } else { 0.30f32 };
+        let rnd = if intra { INTRA_RND } else { INTER_RND };
+        let [dc_thr, ac_thr] = [self.dead_zone[0][intra as usize], self.dead_zone[1][intra as usize]];
         levels.fill(0);
         let mut nonzero = false;
         for (k, (&cf, l)) in coef.iter().zip(levels.iter_mut()).enumerate() {
-            let q = if k == 0 { self.dc_q } else { self.ac_q };
-            let a = (cf.abs() / q + rnd).floor() as i32;
+            let (q, thr) = if k == 0 { (self.dc_q, dc_thr) } else { (self.ac_q, ac_thr) };
+            // dead zone: below the exact threshold the level is zero, no division needed
+            if cf.abs() < thr {
+                continue;
+            }
+            // the operand is >= 0, so truncation equals floor
+            let a = (cf.abs() / q + rnd) as i32;
             if a != 0 {
                 *l = if cf < 0.0 { -a.min(1 << 16) } else { a.min(1 << 16) };
                 nonzero = true;
@@ -913,6 +926,33 @@ impl<'a> Decider<'a> {
     }
 }
 
+/// Smallest `x >= 0` with `(x / q + rnd) as i32 >= 1` in f32 arithmetic. The expression is
+/// monotone in `x`, so a binary search over the bit patterns finds the exact boundary.
+fn zero_threshold(q: f32, rnd: f32) -> f32 {
+    let (mut lo, mut hi) = (0u32, f32::MAX.to_bits());
+    while lo < hi {
+        let mid = lo + (hi - lo) / 2;
+        if (f32::from_bits(mid) / q + rnd) as i32 >= 1 {
+            hi = mid;
+        } else {
+            lo = mid + 1;
+        }
+    }
+    f32::from_bits(lo)
+}
+
+const LOG2_TABLE_LEN: usize = 1025;
+
+/// `log2(i)` for `i < LOG2_TABLE_LEN`, computed with the same `f64::log2` call as the direct form.
+fn log2_table() -> &'static [f64; LOG2_TABLE_LEN] {
+    static TABLE: std::sync::OnceLock<[f64; LOG2_TABLE_LEN]> = std::sync::OnceLock::new();
+    TABLE.get_or_init(|| std::array::from_fn(|i| (i as f64).log2()))
+}
+
+fn log2_of(table: &[f64; LOG2_TABLE_LEN], v: usize) -> f64 {
+    if v < LOG2_TABLE_LEN { table[v] } else { (v as f64).log2() }
+}
+
 /// Unnormalised Walsh-Hadamard transform of 4 or 8 values, in place.
 fn hadamard(v: &mut [i32]) {
     let n = v.len();
@@ -941,13 +981,14 @@ fn estimate_bits(levels: &[i32], tx_sz: usize) -> f64 {
     if eob == 0 {
         return 1.0;
     }
-    let mut bits = 3.0 + (eob as f64).log2();
+    let lg = log2_table();
+    let mut bits = 3.0 + log2_of(lg, eob);
     for &pos in &scan[..eob] {
         let a = levels[pos as usize].unsigned_abs();
         bits += match a {
             0 => 0.7,
             1 => 2.5,
-            _ => 3.5 + 1.6 * (a as f64).log2(),
+            _ => 3.5 + 1.6 * log2_of(lg, a as usize),
         };
     }
     bits
@@ -961,3 +1002,64 @@ pub(crate) fn scan_for(tx_sz: usize) -> &'static [u16] {
         _ => &DEFAULT_SCAN_32X32,
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::tables::{AC_QLOOKUP, DC_QLOOKUP};
+
+    /// The quantiser as it was before the dead-zone threshold and the truncation.
+    fn quant_ref(cf: f32, q: f32, rnd: f32) -> i32 {
+        (cf.abs() / q + rnd).floor() as i32
+    }
+
+    fn quant_new(cf: f32, q: f32, rnd: f32, thr: f32) -> i32 {
+        if cf.abs() < thr {
+            return 0;
+        }
+        (cf.abs() / q + rnd) as i32
+    }
+
+    #[test]
+    fn dead_zone_threshold_is_exact() {
+        let mut state = 0x1234_5678_9abc_def0u64;
+        let mut next = move || {
+            state ^= state << 13;
+            state ^= state >> 7;
+            state ^= state << 17;
+            state
+        };
+        for table in AC_QLOOKUP.iter().chain(DC_QLOOKUP.iter()) {
+            for &qi in table.iter() {
+                let q = qi as f32;
+                for rnd in [INTER_RND, INTRA_RND] {
+                    let thr = zero_threshold(q, rnd);
+                    // the boundary itself and its neighbours
+                    let b = thr.to_bits();
+                    for bits in b.saturating_sub(3)..=b + 3 {
+                        let cf = f32::from_bits(bits);
+                        assert_eq!(quant_ref(cf, q, rnd), quant_new(cf, q, rnd, thr), "q {q} rnd {rnd} cf {cf}");
+                        assert_eq!(quant_ref(-cf, q, rnd), quant_new(-cf, q, rnd, thr));
+                    }
+                    for _ in 0..200 {
+                        let cf = f32::from_bits((next() >> 32) as u32 & 0x7fff_ffff);
+                        if cf.is_nan() {
+                            continue;
+                        }
+                        assert_eq!(quant_ref(cf, q, rnd), quant_new(cf, q, rnd, thr));
+                        let cf = (next() % 100_000) as f32 / 100.0;
+                        assert_eq!(quant_ref(cf, q, rnd), quant_new(cf, q, rnd, thr));
+                    }
+                }
+            }
+        }
+    }
+
+    #[test]
+    fn log2_table_matches_direct_log2() {
+        let t = log2_table();
+        for v in 1..3000usize {
+            assert_eq!(log2_of(t, v).to_bits(), (v as f64).log2().to_bits(), "{v}");
+        }
+    }
+}

crates/effects/src/audio_fx.rs

@@ -206,6 +206,12 @@ pub fn reverses(id: &str) -> bool {
     id == "ec.audio.backwards"
 }
 
+/// Does each output sample depend only on the input sample at the same time (no state), so the
+/// mixer may run the effect in short pieces with parameters animated between them?
+pub fn per_sample(id: &str) -> bool {
+    matches!(id, "ec.audio.stereomixer" | "ec.audio.backwards")
+}
+
 /// Seconds of input history the effect needs before a block to reach the state it would have
 /// had when processing continuously.
 pub fn preroll(id: &str, params: &Params) -> f64 {

crates/effects/src/catalog.rs

@@ -182,6 +182,20 @@ mod tests {
         assert!(have == want, "docs/effects.md is stale: UPDATE_DOCS=1 cargo test -p effectcraft-effects --lib effects_doc_is_current");
     }
 
+    /// The README quotes the number of effects (#2565): every count it gives is the registry's.
+    #[test]
+    fn readme_effect_counts_are_current() {
+        let readme = std::fs::read_to_string(concat!(env!("CARGO_MANIFEST_DIR"), "/../../README.md")).unwrap_or_default();
+        let words: Vec<&str> = readme.split_whitespace().collect();
+        let counts: Vec<&str> = words
+            .windows(3)
+            .filter(|w| w[0].parse::<u32>().is_ok() && (w[1].starts_with("effects") || (w[1] == "built-in" && w[2].starts_with("effects"))))
+            .map(|w| w[0])
+            .collect();
+        let n = super::registry().len().to_string();
+        assert!(!counts.is_empty() && counts.iter().all(|c| *c == n), "README.md says {counts:?} effects; the registry has {n}");
+    }
+
     #[test]
     fn cpu_only_controls_keep_effects_off_the_gpu() {
         use effectcraft_keyframe::Value;

crates/effects/src/channel3d.rs

@@ -7,6 +7,11 @@
 //! pass for a precomp of a 3D comp. Without auxiliary channels they pass the layer through
 //! (EXtractoR still maps the layer's own R, G, B and A).
 //!
+//! 3D Layer Instance (Create 3D Layer Instance's own effect, Layer ▸ Create) is not an aux
+//! reader: it replaces the layer's pixels with a referenced layer's render — for a 3D model
+//! layer, its render on its own through the comp's camera — so 2D effects can be applied to a
+//! 3D layer's render.
+//!
 //! Aux pixels are looked up nearest-neighbour (IDs must not be interpolated) at each buffer
 //! pixel's layer position, so render scale and layer padding are respected.
 
@@ -582,6 +587,19 @@ fn extractor(ctx: &EffectCtx, mut b: Buf) -> Buf {
     b
 }
 
+/// A 2D copy of a referenced layer (Create 3D Layer Instance's solid): the layer's pixels
+/// replaced with the referenced layer's render, alpha included — the copy is transparent
+/// where the referenced layer isn't. A 3D model or primitive layer is rendered on its own
+/// through the comp's camera, as After Effects renders 3D layers; another layer is read with
+/// its masks and effects. With no layer chosen the effect passes the layer through, as a layer
+/// parameter with nothing chosen does.
+fn instance_3d(ctx: &EffectCtx, mut b: Buf) -> Buf {
+    if let Some(o) = ctx.layer_param("layer", true) {
+        b.img = crate::util::fit_layer(ctx, &b, &o, false);
+    }
+    b
+}
+
 pub fn specs() -> Vec<EffectSpec> {
     let text = |id: &'static str, name: &'static str, d: &str| p(id, name, Value::Str(d.into()), ParamUi::Text);
     vec![
@@ -682,6 +700,7 @@ pub fn specs() -> Vec<EffectSpec> {
             ],
             identifier,
         ),
+        spec("ec.3d.instance3d", "3D Layer Instance", vec![p("layer", "Layer", Value::Layer(None), ParamUi::Layer)], instance_3d),
     ]
 }
 

crates/effects/src/channel3d/tests.rs

@@ -373,3 +373,29 @@ fn channel_extract_antialias_averages_sub_pixels() {
     let soft = run("ec.3d.channelextract", &[vals.as_slice(), &[("antialias", Value::Bool(true))]].concat(), &host);
     assert!((soft.get(5, 5)[0] - 0.5).abs() < 1e-5, "{:?}", soft.get(5, 5));
 }
+
+#[test]
+fn instance3d_replaces_the_pixels_with_the_referenced_layer() {
+    // Create 3D Layer Instance's copy: the chosen layer's render takes the place of the layer's
+    // own pixels, alpha included — the copy is transparent where the referenced layer isn't —
+    // and with no layer chosen the layer passes through.
+    struct Host(Image);
+    impl EffectHost for Host {
+        fn layer(&self, id: u64, _: bool) -> Option<LayerPixels> {
+            (id == 7).then(|| LayerPixels { buf: Buf { img: self.0.clone(), offset: [0.0; 2], scale: 1.0 }, size: [self.0.width as f64, self.0.height as f64] })
+        }
+        fn audio(&self, _: u64, _: f64, _: usize, _: u32) -> Option<Vec<f32>> {
+            None
+        }
+    }
+    let solid = || Image::filled(4, 4, [1.0, 1.0, 1.0, 1.0]);
+    let mut render = Image::new(4, 4);
+    render.set(1, 1, [1.0, 0.0, 0.0, 1.0]);
+    let env = EffectEnv { host: Some(&Host(render)), ..Default::default() };
+    let out = run_fx("ec.3d.instance3d", &[("layer", Value::Layer(Some(7)))], solid(), 0.0, env);
+    assert_eq!(out.img.get(1, 1), [1.0, 0.0, 0.0, 1.0], "the referenced layer's pixel");
+    assert_eq!(out.img.get(3, 3), [0.0; 4], "transparent where the referenced layer isn't");
+    // No layer chosen: the layer's own pixels.
+    let out = run_fx("ec.3d.instance3d", &[], solid(), 0.0, EffectEnv::default());
+    assert_eq!(out.img.data, solid().data);
+}

crates/effects/src/distort2.rs

@@ -95,6 +95,9 @@ fn turbulent_displace(ctx: &EffectCtx, mut b: Buf) -> Buf {
     let size = (ctx.params.f("size") * b.scale).max(1.0);
     if ctx.params.b("resizeLayer") && !ctx.adjustment {
         b.pad(amount.abs().ceil() as u32 + 1);
+    } else {
+        // Room for pixels displaced past the content, up to the layer's edge (#1205).
+        b.pad(crate::cover_pad(ctx, [b.img.width, b.img.height], b.offset, b.scale, amount.abs().ceil() as u32 + 1));
     }
     let off = b.to_px(ctx.params.v2("offset"));
     let oct = ctx.params.f("complexity").clamp(1.0, 10.0);

crates/effects/src/lib.rs

@@ -312,17 +312,47 @@ impl Buf {
         self.offset[0] += l as f64;
         self.offset[1] += t as f64;
     }
-    /// Grow by `pad` transparent pixels on every side.
+    /// Grow by `left` and `top` transparent pixels on those sides only.
+    pub fn grow_left_top(&mut self, left: u32, top: u32) {
+        self.pad_sides([left, top, 0, 0]);
+    }
+    /// Give the buffer the pixel-grid phase (modulo [`GRID_ALIGN`]) that [`Buf::cover`] of
+    /// `size` would, by growing left/top only ([`align_plan`]). A downscaled layer is resampled
+    /// through a pyramid whose 2x2 blocks follow the buffer's grid, so a buffer that starts at
+    /// its content's corner instead of the cover's resamples to different pixels (#1205).
+    pub fn align(&mut self, size: [f64; 2]) {
+        if let Some((l, t)) = align_plan(self.offset, self.scale, size, self.img.width, self.img.height) {
+            self.grow_left_top(l, t);
+        }
+    }
+    /// Grow by `pad` transparent pixels on every side, within [`pad_within_budget`] and as
+    /// clamped by [`Image::effective_pad`].
     pub fn pad(&mut self, pad: u32) {
-        if pad == 0 {
+        let eff = self.img.effective_pad(pad_within_budget(self.img.width, self.img.height, pad));
+        if eff == 0 {
             return;
         }
-        self.img = self.img.padded(pad);
-        self.offset[0] += pad as f64;
-        self.offset[1] += pad as f64;
+        self.img = self.img.padded(eff);
+        self.offset[0] += eff as f64;
+        self.offset[1] += eff as f64;
     }
 }
 
+/// `pad` on every side of a `w` × `h` effect buffer, cut so the padded buffer stays within
+/// 16 Mpx (256 MiB of f32 RGBA) or four times its own area, whichever is larger: a small layer
+/// far from an effect's centre can't ask for gigabytes (#2261). Shared with the GPU path.
+pub fn pad_within_budget(w: u32, h: u32, pad: u32) -> u32 {
+    const MIN_BUDGET: f64 = 16_777_216.0;
+    let (w, h) = (f64::from(w), f64::from(h));
+    let budget = MIN_BUDGET.max(4.0 * w * h);
+    if (w + 2.0 * f64::from(pad)) * (h + 2.0 * f64::from(pad)) <= budget {
+        return pad;
+    }
+    // (w + 2p)(h + 2p) = budget, solved for p.
+    let p = (((w - h).powi(2) + 4.0 * budget).sqrt() - (w + h)) / 4.0;
+    (p.floor().max(0.0) as u32).min(pad)
+}
+
 /// Motion Tile's output frame for a buffer with layer origin `offset` (pixels) at `scale`:
 /// `(width, height, offset)`. Output Width / Height grow (or crop) the layer rectangle about its
 /// centre, on adjustment layers too, where the rectangle is the comp's and starts at the comp
@@ -360,6 +390,33 @@ pub fn adjustment_crop(offset: [f64; 2], canvas_offset: [f64; 2], size: (u32, u3
     Some((dx as i64, dy as i64))
 }
 
+/// Effects that grow their own buffer by what they need (blur and glow margins, Repeat Edge
+/// Pixels through [`Buf::cover`], displacement through [`cover_pad`]): a stack of only these
+/// skips the renderer's cover of the whole layer rectangle (#1205).
+pub const SKIPS_COVER: &[&str] = &["ec.blur.gaussian", "ec.blur.fastbox", "ec.stylize.glow", "ec.distort.turbulentdisplace"];
+
+/// The grid phase [`Buf::align`] keeps and the step [`cover_pad`] grows in: covers the levels
+/// of the resampling pyramid used for downscaled layers.
+pub const GRID_ALIGN: u32 = 64;
+
+/// Left/top growth giving a buffer [`cover_plan`]'s grid phase modulo [`GRID_ALIGN`]; `None`
+/// when there is nothing to add.
+pub fn align_plan(offset: [f64; 2], scale: f64, size: [f64; 2], width: u32, height: u32) -> Option<(u32, u32)> {
+    let (dx, dy, _, _) = cover_plan(offset, scale, size, width, height)?;
+    let (l, t) = (dx % GRID_ALIGN, dy % GRID_ALIGN);
+    (l != 0 || t != 0).then_some((l, t))
+}
+
+/// Padding for an effect that moves pixels up to `want` past the content (not an adjustment
+/// layer): `want`, capped at what reaches the layer rectangle, in whole [`GRID_ALIGN`] steps so
+/// the grid phase stays. 0 once the buffer covers the layer.
+pub fn cover_pad(ctx: &EffectCtx, size: [u32; 2], offset: [f64; 2], scale: f64, want: u32) -> u32 {
+    if ctx.adjustment {
+        return 0;
+    }
+    want.min(util::layer_cover_pad(ctx, size, offset, scale)).div_ceil(GRID_ALIGN) * GRID_ALIGN
+}
+
 /// Where [`Buf::cover`] would take a buffer: shift its pixels by `(dx, dy)` and resize it to
 /// `width` × `height` so it spans the `size`-layer-pixel region that starts at its offset — the
 /// whole layer rectangle, which a sized source's buffer already is. `None` when the buffer
@@ -538,6 +595,15 @@ pub struct EffectSpec {
     pub float: bool,
 }
 
+impl EffectSpec {
+    /// True when this effect grows its own buffer (blur/glow margins, Repeat Edge
+    /// [`Buf::cover`], displacement [`cover_pad`]) so a stack of only these can skip the
+    /// renderer's full-layer cover and keep the pyramid grid phase (#1205).
+    pub fn skips_cover(&self) -> bool {
+        SKIPS_COVER.contains(&self.id)
+    }
+}
+
 pub(crate) fn p(id: &'static str, name: &'static str, default: Value, ui: ParamUi) -> ParamSpec {
     ParamSpec { id, name, default, ui }
 }
@@ -1344,6 +1410,23 @@ pub(crate) fn run_fx(id: &str, vals: &[(&str, Value)], img: Image, time: f64, en
 mod tests {
     use super::*;
 
+    /// #2261: a 20 × 20 layer with CC Radial Fast Blur's Center far away grows to at most 16 Mpx;
+    /// big layers may still grow to four times their area, and small pads are untouched.
+    #[test]
+    fn padded_buffers_stay_within_the_budget() {
+        let area = |w: u32, h: u32, p: u32| (u64::from(w) + 2 * u64::from(p)) * (u64::from(h) + 2 * u64::from(p));
+        let far = radial_fast_pad((6500.0, 6500.0), 20, 20, 0.8);
+        assert_eq!(far, 4096, "the effect asks for its full pad");
+        let mut b = Buf { img: Image::new(20, 20), offset: [0.0; 2], scale: 1.0 };
+        b.pad(far);
+        assert!(area(20, 20, 0) < area(b.img.width, b.img.height, 0) && area(b.img.width, b.img.height, 0) <= 1 << 24, "{}x{}", b.img.width, b.img.height);
+        assert_eq!(b.offset, [f64::from((b.img.width - 20) / 2); 2], "the content keeps its place");
+        let p = pad_within_budget(3840, 2160, 4096);
+        assert!(p > 1000 && area(3840, 2160, p) <= 4 * 3840 * 2160 && area(3840, 2160, p + 1) > 4 * 3840 * 2160);
+        assert_eq!(pad_within_budget(640, 360, 200), 200);
+        assert_eq!(pad_within_budget(20, 20, 0), 0);
+    }
+
     #[test]
     fn run_fx_passthrough() {
         let img = Image::filled(4, 3, [0.5, 0.25, 0.125, 1.0]);
@@ -1351,6 +1434,20 @@ mod tests {
         assert_eq!(out.img.data, img.data);
     }
 
+    #[test]
+    fn pad_offset_follows_the_clamped_pad() {
+        // Image::padded clamps a hostile pad to keep each side within MAX_PADDED_SIDE; the offset
+        // must move by the pad actually applied, or the content drifts from its layer position.
+        let mut img = Image::new(29_990, 2);
+        img.set(0, 0, [1.0, 0.0, 0.0, 1.0]);
+        let mut buf = Buf { img, offset: [3.0, 4.0], scale: 1.0 };
+        buf.pad(u32::MAX);
+        // Width binds: (MAX_PADDED_SIDE - 29 990) / 2 = 5.
+        assert_eq!(buf.offset, [8.0, 9.0]);
+        let (x, y) = buf.to_px([-3.0, -4.0]);
+        assert_eq!(buf.img.get(x as i64, y as i64), [1.0, 0.0, 0.0, 1.0]);
+    }
+
     #[test]
     #[ignore]
     fn dump_registry() {
@@ -1535,4 +1632,24 @@ mod tests {
         assert_eq!(g.get("noiseSourceLayerSource").map(|p| p.value.clone()), Some(Value::Enum(0)));
         assert_eq!(g.props().filter(|p| p.match_id == "noiseSourceLayerSource").count(), 1);
     }
+
+    #[test]
+    fn align_plan_is_cover_shift_mod_grid() {
+        // Content inset from the layer origin: pixel 0 maps to layer (50, 30).
+        let offset = [-50.0, -30.0];
+        let scale = 1.0;
+        let size = [1920.0, 1080.0];
+        let (dx, dy, _, _) = cover_plan(offset, scale, size, 80, 40).unwrap();
+        assert_eq!((dx, dy), (50, 30));
+        assert_eq!(align_plan(offset, scale, size, 80, 40), Some((50, 30)));
+        assert_eq!(align_plan([-64.0, -128.0], 1.0, size, 80, 40), None);
+    }
+
+    #[test]
+    fn known_margin_effects_skip_cover_and_twirl_does_not() {
+        for id in SKIPS_COVER {
+            assert!(find(id).expect(id).skips_cover(), "{id}");
+        }
+        assert!(!find("ec.distort.twirl").unwrap().skips_cover());
+    }
 }

crates/effects/src/misc.rs

@@ -34,6 +34,9 @@ fn gaussian(ctx: &EffectCtx, mut b: Buf) -> Buf {
     let repeat = ctx.params.b("repeatEdge");
     if !repeat && !ctx.adjustment {
         b.pad((s * 3.0).ceil() as u32);
+    } else if repeat && !ctx.adjustment {
+        // The edge it repeats is the layer's, not the painted content's (#1205).
+        b.cover(ctx.layer_size);
     }
     let (sx, sy) = (s * kx, s * ky);
     // Small sigmas: integer-radius box passes would step (and do nothing below ~0.6 px), so sample the kernel (#1939).
@@ -60,6 +63,9 @@ fn box_blur(ctx: &EffectCtx, mut b: Buf) -> Buf {
     if !repeat && !ctx.adjustment {
         let reach = if frac > 0.0 { r + 1 } else { r };
         b.pad((reach * it) as u32 + 1);
+    } else if repeat && !ctx.adjustment {
+        // The edge it repeats is the layer's, not the painted content's (#1205).
+        b.cover(ctx.layer_size);
     }
     let edge = repeat || ctx.adjustment;
     let lo = effectcraft_raster::box_blur(&b.img, r * kx as usize, r * ky as usize, it, edge);

crates/effects/src/utility.rs

@@ -100,17 +100,11 @@ impl Cineon {
     fn knee(&self) -> f32 {
         1.0 - (self.rolloff / 100.0).clamp(0.0, 0.99)
     }
-    /// Normalised code value (code / 1023) → linear.
+    /// Normalized code value (code / 1023) → linear, raised to `1.7 / gamma`
+    /// ([`effectcraft_project::cineon_log_to_lin`], which Interpret Footage ▸ Cineon Settings
+    /// also uses with `1 / gamma`).
     pub fn log_to_lin(&self, v: f32) -> f32 {
-        let off = self.offset();
-        let code = v * 1023.0;
-        let mut lin = (10f32.powf((code - self.white) * 0.002 / 0.6) - off) / (1.0 - off).max(1e-6);
-        lin = lin.max(0.0).powf(1.7 / self.gamma.max(0.01));
-        let k = self.knee();
-        if k < 1.0 && lin > k {
-            let w = 1.0 - k;
-            lin = k + w * (1.0 - (-(lin - k) / w).exp());
-        }
+        let lin = effectcraft_project::cineon_log_to_lin(v, self.black, self.white, 1.7, self.gamma, self.rolloff);
         self.ib + (self.iw - self.ib) * lin
     }
     /// Linear → normalised code value.
@@ -495,6 +489,87 @@ mod tests {
         assert!(c.log_to_lin(95.0 / 1023.0).abs() < 1e-4);
     }
 
+    /// Interpret Footage ▸ Cineon Settings and the Cineon Converter's Log to Linear give the same
+    /// values for the same points and Highlight Rolloff when the converter's Gamma is 1.7 times
+    /// Cineon Settings' Gamma: the converter's default 1.7 and Cineon Settings' Gamma 1 both give
+    /// linear light (code 400 is 0.10251).
+    #[test]
+    fn cineon_converter_matches_interpret_footage() {
+        let codes = [0.0f32, 95.0, 250.0, 400.0, 560.0, 685.0, 800.0, 1023.0];
+        for (gamma, rolloff) in [(1.0, 20.0), (1.0, 0.0), (1.7, 50.0), (2.4, 50.0)] {
+            let mut img = Image::new(codes.len() as u32, 1);
+            for (x, code) in codes.iter().enumerate() {
+                let v = code / 1023.0;
+                img.set(x as u32, 0, [v, v, v, 1.0]);
+            }
+            let vals = [("conversionType", Value::Enum(1)), ("gamma", num(gamma * 1.7)), ("highlightRolloff", num(rolloff))];
+            let out = run("ec.utility.cineon", &vals, img);
+            let settings = effectcraft_project::CineonSettings { log_conversion: true, gamma: gamma as f32, rolloff: rolloff as f32, ..Default::default() };
+            for (x, code) in codes.iter().enumerate() {
+                let footage = settings.convert(code / 1023.0);
+                let effect = out.img.data[x][0];
+                assert!((footage - effect).abs() < 1e-6, "gamma {gamma}, rolloff {rolloff}, code {code}: {footage} vs {effect}");
+            }
+        }
+        let linear = effectcraft_project::CineonSettings { gamma: 1.0, rolloff: 0.0, ..Default::default() };
+        assert!((linear.convert(400.0 / 1023.0) - 0.10251).abs() < 1e-4);
+    }
+
+    /// The Cineon Converter gives the same values as before Cineon Settings shared its
+    /// log-to-linear function, at the default Gamma (1.7) and at Gamma 2.4, for all three
+    /// conversion types.
+    #[test]
+    fn cineon_converter_output_is_unchanged() {
+        fn log_to_lin(v: f32, gamma: f32, rolloff: f32, black: f32, white: f32) -> f32 {
+            let off = 10f32.powf((black - white) * 0.002 / 0.6);
+            let mut lin = (10f32.powf((v * 1023.0 - white) * 0.002 / 0.6) - off) / (1.0 - off).max(1e-6);
+            lin = lin.max(0.0).powf(1.7 / gamma.max(0.01));
+            let k = 1.0 - (rolloff / 100.0).clamp(0.0, 0.99);
+            if k < 1.0 && lin > k {
+                let w = 1.0 - k;
+                lin = k + w * (1.0 - (-(lin - k) / w).exp());
+            }
+            lin
+        }
+        fn lin_to_log(v: f32, gamma: f32, rolloff: f32, black: f32, white: f32) -> f32 {
+            let off = 10f32.powf((black - white) * 0.002 / 0.6);
+            let mut lin = v;
+            let k = 1.0 - (rolloff / 100.0).clamp(0.0, 0.99);
+            if k < 1.0 && lin > k {
+                let w = 1.0 - k;
+                lin = k - w * (1.0 - (lin - k) / w).max(1e-6).ln();
+            }
+            lin = lin.max(0.0).powf(gamma.max(0.01) / 1.7);
+            (white + (lin * (1.0 - off) + off).max(1e-9).log10() * 0.6 / 0.002) / 1023.0
+        }
+        let codes = [0.0f32, 95.0, 250.0, 400.0, 560.0, 685.0, 800.0, 1023.0];
+        for gamma in [None, Some(2.4)] {
+            for kind in 0..3 {
+                let mut img = Image::new(codes.len() as u32, 1);
+                for (x, code) in codes.iter().enumerate() {
+                    let v = code / 1023.0;
+                    img.set(x as u32, 0, [v, v, v, 1.0]);
+                }
+                let mut vals = vec![("conversionType", Value::Enum(kind))];
+                if let Some(g) = gamma {
+                    vals.push(("gamma", num(g)));
+                }
+                let out = run("ec.utility.cineon", &vals, img);
+                let g = gamma.unwrap_or(1.7) as f32;
+                for (x, code) in codes.iter().enumerate() {
+                    let v = code / 1023.0;
+                    let want = match kind {
+                        0 => lin_to_log(v, g, 20.0, 95.0, 685.0),
+                        1 => log_to_lin(v, g, 20.0, 95.0, 685.0),
+                        _ => lin_to_log(log_to_lin(v, g, 20.0, 95.0, 685.0), 1.7, 20.0, 95.0, 685.0),
+                    };
+                    let got = out.img.data[x][0];
+                    assert!((want - got).abs() < 1e-6, "gamma {g}, type {kind}, code {code}: {want} vs {got}");
+                }
+            }
+        }
+    }
+
     #[test]
     fn hdr_compression_behaviour() {
         let mut img = Image::new(2, 1);

crates/engine/presets/text_animators.json

@@ -77,7 +77,7 @@
           "name": "Tracking In",
           "properties": { "tracking": 0, "opacity": 100 },
           "keys": {
-            "tracking": [[0, 400], [1.6, 0]],
+            "tracking": [[0, 40], [1.6, 0]],
             "opacity": [[0, 0], [0.8, 100]]
           },
           "ease": true,

crates/engine/src/analysis/tracking.rs

@@ -197,7 +197,8 @@ pub(crate) struct Work {
 }
 
 /// The layer's source frame at comp time `t` at 100 % (layer pixels + offset = image pixels).
-/// Footage at its native size is used straight from the footage source (no copy).
+/// Footage at its native size is used straight from the footage source (no copy unless its
+/// Cineon Settings convert it).
 pub(crate) fn source_frame(
     r: &Renderer,
     project: &Project,
@@ -207,7 +208,7 @@ pub(crate) fn source_frame(
     t: Tick,
     expr: Option<&dyn ExprHost>,
 ) -> Option<(Arc<Image>, [f64; 2])> {
-    let ctx = EvalCtx { project, comp_id: cid, comp, time: t, expr, footage: None };
+    let ctx = EvalCtx { project, comp_id: cid, comp, time: t, expr, footage: None, property_overrides: &[], media_overrides: &[] };
     if let effectcraft_project::LayerSource::Footage { item } = &layer.source
         && let Some(effectcraft_project::ItemKind::Footage(f)) = project.item(*item).map(|i| &i.kind)
         && f.has_video
@@ -215,7 +216,7 @@ pub(crate) fn source_frame(
         && img.width == f.width
         && img.height == f.height
     {
-        return Some((img, [0.0; 2]));
+        return Some((effectcraft_render::cineon_frame(img, f), [0.0; 2]));
     }
     let buf = r.layer_source(&ctx, layer)?;
     if (buf.scale - 1.0).abs() > 1e-9 && buf.scale > 0.0 {

crates/engine/src/cmd/app_more.rs

@@ -152,7 +152,7 @@ fn clear_recent_presets(s: &mut Session, _: &Value) -> Result<Value> {
 
 fn save_copy_xml(s: &mut Session, p: &Value) -> Result<Value> {
     let path = str_p(p, "path").ok_or_else(|| bad("file.saveCopyAsXml", "missing `path` (.ecprojx)"))?;
-    let xml = crate::xml_project::to_xml(&s.project.to_file_json_with_view(&s.saved_view())?).map_err(EngineError::Other)?;
+    let xml = crate::xml_project::to_xml(&s.project.to_file_json_with_view(&s.saved_view(), false)?).map_err(EngineError::Other)?;
     s.services.write_file(path, xml.as_bytes()).map_err(|e| EngineError::Other(format!("cannot write {path}: {e}")))?;
     s.toast(format!("Saved an XML copy to {path}"));
     Ok(json!({"path": path, "bytes": xml.len()}))
@@ -240,7 +240,7 @@ fn replace_with_precomp(s: &mut Session, p: &Value) -> Result<Value> {
             let ids: Vec<ItemId> = proj.items.keys().copied().filter(|c| *c != comp).collect();
             for cid in ids {
                 if let Some(c) = proj.comp_mut(cid) {
-                    for l in c.layers.iter_mut().filter(|l| is_user(l)) {
+                    for l in c.layers.iter_mut_where(|l| is_user(l)) {
                         l.source = LayerSource::Comp { item: comp };
                         n += 1;
                     }

crates/engine/src/cmd/batch.rs

@@ -9,8 +9,9 @@ use serde_json::{Value, json};
 use super::{CommandSpec, always, bad, str_p};
 use crate::{EngineError, Result, Session};
 
-/// Commands that can't run inside a batch (they replace the project or nest batches).
-const NOT_IN_BATCH: &[&str] = &["engine.batch", "file.runScript", "script.run"];
+/// Commands that can't run inside a batch (they nest batches), besides the commands that run
+/// scripts ([`super::scripts::RUNS_SCRIPTS`]).
+const NOT_IN_BATCH: &[&str] = &["engine.batch"];
 
 /// Resolve a `$N` / `$N.key.0.key` reference against the results so far.
 fn reference(s: &str, results: &[Value]) -> Option<Result<Value>> {
@@ -78,7 +79,7 @@ fn batch(s: &mut Session, p: &Value) -> Result<Value> {
                 .or_else(|| step.get("id"))
                 .and_then(Value::as_str)
                 .ok_or_else(|| bad("engine.batch", "each step needs `command` (a command id)"))?;
-            if NOT_IN_BATCH.contains(&id) {
+            if NOT_IN_BATCH.contains(&id) || super::scripts::RUNS_SCRIPTS.contains(&id) {
                 return Err(bad("engine.batch", format!("`{id}` can't run inside a batch")));
             }
             let params = substitute(step.get("params").unwrap_or(&json!({})), results)?;

crates/engine/src/cmd/comp.rs

@@ -35,7 +35,7 @@ fn apply_settings(c: &mut Comp, p: &Value) {
         let dx = (c.width as f64 - ow as f64) * (a % 3) as f64 / 2.0;
         let dy = (c.height as f64 - oh as f64) * (a / 3) as f64 / 2.0;
         if dx != 0.0 || dy != 0.0 {
-            for l in c.layers.iter_mut().filter(|l| l.parent.is_none()) {
+            for l in c.layers.iter_mut_where(|l| l.parent.is_none()) {
                 if let Some(tr) = l.transform_mut() {
                     super::layer::offset_position(tr, dx, dy);
                 }

crates/engine/src/cmd/comp_more.rs

@@ -5,7 +5,7 @@ use effectcraft_project::Marker;
 use effectcraft_time::Tick;
 use serde_json::{Value, json};
 
-use super::{CommandSpec, always, bad, comp_id, f_p, has_comp, has_layers, layers_p, str_p};
+use super::{CommandSpec, always, b_p, bad, comp_id, f_p, has_comp, has_layers, layers_p, str_p};
 use crate::prefs::CompPreset;
 use crate::{EngineError, Result, Session, cmd, query};
 
@@ -25,7 +25,7 @@ fn crop(s: &mut Session, cid: effectcraft_project::ItemId, r: [f64; 4], label: &
         let (old_w, old_h) = (c.width, c.height);
         c.width = w;
         c.height = h;
-        for l in c.layers.iter_mut().filter(|l| l.parent.is_none()) {
+        for l in c.layers.iter_mut_where(|l| l.parent.is_none()) {
             if let Some(tr) = l.transform_mut() {
                 super::layer::offset_position(tr, -x, -y);
             }
@@ -82,7 +82,7 @@ pub(crate) fn encode_png(rgba: &[u8], w: u32, h: u32) -> std::result::Result<Vec
 /// Save Frame As ▸ File with `queue`: a Render Queue item for the current frame, from the Frame
 /// Default templates (Edit ▸ Templates).
 fn queue_frame(s: &mut Session, p: &Value) -> Result<Value> {
-    use effectcraft_project::render_queue::{RenderQueueItem, TimeSpan};
+    use effectcraft_project::render_queue::{Channels, RenderQueueItem, TimeSpan};
     use effectcraft_project::render_templates::TemplateSlot;
     let cid = comp_id(s, p)?;
     let comp = s.project.comp(cid).ok_or(EngineError::NoComp)?;
@@ -91,6 +91,9 @@ fn queue_frame(s: &mut Session, p: &Value) -> Result<Value> {
     it.settings = s.project.render_templates.default_render_settings(TemplateSlot::Still);
     it.settings.time_span = TimeSpan::Custom { start: t, end: t + comp.frame_duration() };
     it.output = s.project.render_templates.default_output_module(TemplateSlot::Still);
+    if b_p(p, "transparent") == Some(false) {
+        it.output.channels = Channels::Rgb;
+    }
     if let Some(path) = str_p(p, "path") {
         it.output.output = path.to_string();
     } else if !it.output.format.is_sequence() {
@@ -107,7 +110,7 @@ fn queue_frame(s: &mut Session, p: &Value) -> Result<Value> {
 }
 
 fn save_frame(s: &mut Session, p: &Value) -> Result<Value> {
-    if p.get("queue").and_then(Value::as_bool) == Some(true) {
+    if b_p(p, "queue") == Some(true) {
         return queue_frame(s, p);
     }
     let path = str_p(p, "path").ok_or_else(|| bad("comp.saveFrameAs", "missing `path` (.png)"))?.to_string();
@@ -117,7 +120,7 @@ fn save_frame(s: &mut Session, p: &Value) -> Result<Value> {
     let scale = f_p(p, "scale").unwrap_or(1.0).clamp(0.01, 4.0);
     let bg = comp.background;
     let img = s.render(cid, t, effectcraft_render::RenderOpts { scale, backend: effectcraft_render::Backend::Auto, ..Default::default() });
-    let rgba = img.to_rgba8_over(bg);
+    let rgba = if b_p(p, "transparent") == Some(false) { img.to_rgba8_over(bg) } else { img.to_rgba8() };
     let png = encode_png(&rgba, img.width, img.height).map_err(|e| EngineError::Other(format!("PNG encoding failed: {e}")))?;
     s.services.write_file(&path, &png).map_err(|e| EngineError::Other(format!("cannot write {path}: {e}")))?;
     s.toast(format!("Saved frame to {path}"));
@@ -235,7 +238,7 @@ pub fn specs() -> Vec<CommandSpec> {
             "File...",
             ["Composition", "Save Frame As"],
             Some("Cmd+Alt+S"),
-            "{path (.png; with queue: an output path or template), time?, scale?, queue?: bool (add a Render Queue item from the Frame Default templates instead of writing now)}",
+            "{path (.png; with queue: an output path or template), time?, scale?, queue?: bool (add a Render Queue item from the Frame Default templates instead of writing now), transparent?: bool (default true)}",
             has_comp,
             save_frame
         ),

crates/engine/src/cmd/create.rs

@@ -1,14 +1,17 @@
 //! Layer ▸ Create: Convert to Editable Text (Photoshop type layers), Create Shapes from Text,
-//! Create Masks from Text and Create Shapes from Vector Layer (SVG footage).
+//! Create Masks from Text, Create Shapes from Vector Layer (SVG footage) and Create 3D Layer
+//! Instance (a 2D copy of a 3D model layer that 2D effects can be applied to).
 
 use effectcraft_color::Label;
+use effectcraft_keyframe::Value as KV;
+use effectcraft_project::build::{self, Ids};
 use effectcraft_project::{ItemKind, LayerSource, Solid};
 use serde_json::{Value, json};
 
 use super::{CommandSpec, bad, has_layers, layers_p, str_p};
 use crate::{EngineError, Result, Session, cmd};
 
-const OPS: &str = "editableText|shapesFromText|masksFromText|shapesFromVector";
+const OPS: &str = "editableText|shapesFromText|masksFromText|shapesFromVector|instance3d";
 
 fn create(s: &mut Session, p: &Value) -> Result<Value> {
     let op = str_p(p, "op").ok_or_else(|| bad("layer.create", format!("missing `op` ({OPS})")))?;
@@ -19,6 +22,69 @@ fn create(s: &mut Session, p: &Value) -> Result<Value> {
     let time = s.time();
     let mut created = vec![];
     let mut skipped = vec![];
+    // All the selected models in one edit: one undo (or redo) removes (or restores) every
+    // instance at once, as one command in the History panel.
+    if op == "instance3d" {
+        // After Effects' Create 3D Layer Instance (Layer ▸ Create): 3D model layers take
+        // no masks or effects, so a comp-sized solid goes at the top of the layer stack
+        // with a 3D Layer Instance effect referencing the model — a 2D copy of its render,
+        // through the comp's camera, that 2D effects can be applied to. The model is switched
+        // off, as After Effects does (back on to keep its shadow).
+        let comp = s.project.comp(cid).ok_or(EngineError::NoComp)?.clone();
+        let mut eligible = vec![];
+        for lid in &lids {
+            match comp.layer(*lid) {
+                Some(src) if src.source.is_model() => eligible.push((*lid, src.clone())),
+                Some(src) => skipped.push(format!("{}: not a 3D model layer", src.name)),
+                None => {}
+            }
+        }
+        if !eligible.is_empty() {
+            let ids = s.edit("Create 3D Layer Instance", None, |proj, st| {
+                let mut ids = vec![];
+                for (lid, src) in &eligible {
+                    let name = proj.comp(cid).ok_or(EngineError::NoComp)?.unique_layer_name(&format!("{} Instance", src.name));
+                    let folder = proj.folder_named("Solids").unwrap_or_else(|| proj.add_item("Solids", Label::Yellow, None, ItemKind::Folder));
+                    let sid = proj.add_item(
+                        &name,
+                        src.label,
+                        Some(folder),
+                        ItemKind::Solid(Solid { color: [1.0, 1.0, 1.0], width: comp.width, height: comp.height, pixel_aspect: 1.0 }),
+                    );
+                    let mut l = build::layer(proj, &comp, &name, LayerSource::Solid { item: sid }, (comp.width, comp.height), None);
+                    // A soloed source keeps its Solo switch with video off, and any_solo hides
+                    // the non-soloed copy: the copy takes the Solo over to stay visible.
+                    l.switches.solo = src.switches.solo;
+                    // A 3D Layer Instance effect referencing the 3D layer: the solid shows its
+                    // render (the 2D copy).
+                    let fx = effectcraft_effects::find("ec.3d.instance3d").ok_or_else(|| bad("layer.create", "the 3D Layer Instance effect is missing"))?;
+                    let mut g = effectcraft_effects::instantiate(fx, &mut Ids(&mut proj.next_id), fx.name, [comp.width as f64, comp.height as f64]);
+                    if let Some(pr) = g.get_mut("layer") {
+                        pr.value = KV::Layer(Some(lid.0));
+                    }
+                    if let Some(fxg) = l.props.sub_mut("effects") {
+                        fxg.children.push(g.into());
+                    }
+                    // The model is switched off (After Effects turns the referenced layer off);
+                    // the copies go at the top of the stack, selected.
+                    let c = proj.comp_mut(cid).ok_or(EngineError::NoComp)?;
+                    if let Some(m) = c.layers.iter_mut().find(|x| x.id == *lid) {
+                        m.switches.video = false;
+                    }
+                    let id = l.id;
+                    c.layers.insert(0, l);
+                    ids.push(id);
+                }
+                st.selected_layers = ids.clone();
+                Ok(ids)
+            })?;
+            created.extend(ids.iter().map(|i| i.0));
+        }
+        if created.is_empty() && !skipped.is_empty() {
+            return Err(bad("layer.create", skipped.join("; ")));
+        }
+        return Ok(json!({"layers": created, "skipped": skipped}));
+    }
     for lid in lids {
         let comp = s.project.comp(cid).ok_or(EngineError::NoComp)?.clone();
         let Some(src) = comp.layer(lid).cloned() else { continue };
@@ -198,5 +264,5 @@ fn insert_above(
 }
 
 pub fn specs() -> Vec<CommandSpec> {
-    vec![cmd!("layer.create", "Create", [], None, "{op: editableText|shapesFromText|masksFromText|shapesFromVector, layers?}", has_layers, create)]
+    vec![cmd!("layer.create", "Create", [], None, "{op: editableText|shapesFromText|masksFromText|shapesFromVector|instance3d, layers?}", has_layers, create)]
 }

crates/engine/src/cmd/edit.rs

@@ -74,9 +74,9 @@ fn select_all(s: &mut Session, _: &Value) -> Result<Value> {
     Ok(json!(s.state.selected_layers.len()))
 }
 fn deselect_all(s: &mut Session, _: &Value) -> Result<Value> {
-    // A deselected layer never keeps an open text edit: commit the edit first, exactly as
-    // `text.endEdit` (an empty Type-tool layer included), so every route — menu, shortcut,
-    // script, MCP — leaves one final state.
+    // A deselected layer never keeps an open text edit: commit it first, exactly as `text.endEdit`,
+    // so every route — menu, shortcut, script, MCP — leaves one final state. An empty Type-tool
+    // layer survives, as it does in After Effects.
     super::text_edit::end_edit(s, &Value::Null)?;
     s.state.selected_layers.clear();
     s.state.selected_props.clear();
@@ -90,7 +90,7 @@ fn deselect_all(s: &mut Session, _: &Value) -> Result<Value> {
 fn relink_copies(comp: &mut Comp, map: &[(LayerId, LayerId)]) {
     let present: Vec<LayerId> = comp.layers.iter().map(|l| l.id).collect();
     let link = |id: LayerId| map.iter().find(|(o, _)| *o == id).map(|(_, c)| *c).or(present.contains(&id).then_some(id));
-    for l in comp.layers.iter_mut().filter(|l| map.iter().any(|(_, c)| *c == l.id)) {
+    for l in comp.layers.iter_mut_where(|l| map.iter().any(|(_, c)| *c == l.id)) {
         l.parent = l.parent.and_then(link);
         l.track_matte = l.track_matte.and_then(|m| link(m.layer).map(|layer| TrackMatte { layer, ..m }));
     }
@@ -146,6 +146,11 @@ fn duplicate(s: &mut Session, p: &Value) -> Result<Value> {
         st.selected_layers = created.clone();
         Ok(created)
     })?;
+    // Duplicating selects the copies, so an open text edit on a now-deselected layer ends
+    // (#2226): typing must not keep editing an unselected layer.
+    if s.state.text_edit.as_ref().is_some_and(|e| !s.state.selected_layers.contains(&e.layer)) {
+        super::text_edit::end_edit(s, &Value::Null)?;
+    }
     Ok(json!(new.iter().map(|l| l.0).collect::<Vec<_>>()))
 }
 
@@ -680,7 +685,7 @@ fn label(s: &mut Session, p: &Value) -> Result<Value> {
             }
         }
         if let Some(comp) = proj.comp_mut(cid) {
-            for l in comp.layers.iter_mut().filter(|l| ids.contains(&l.id)) {
+            for l in comp.layers.iter_mut_where(|l| ids.contains(&l.id)) {
                 l.label = lab;
             }
         }

crates/engine/src/cmd/effect.rs

@@ -136,7 +136,16 @@ fn warning(s: &mut Session, p: &Value) -> Result<Value> {
     let layer = comp.layer(lid).ok_or(EngineError::NoComp)?;
     let g = layer.effects().and_then(|fx| fx.groups().find(|g| g.uid == uid)).ok_or_else(|| bad(cmd, "no such effect"))?;
     let t = super::time_p(s, p, Some(comp));
-    let ctx = effectcraft_render::EvalCtx { project: &s.project, comp_id: cid, comp, time: t, expr: s.expr.as_deref(), footage: None };
+    let ctx = effectcraft_render::EvalCtx {
+        project: &s.project,
+        comp_id: cid,
+        comp,
+        time: t,
+        expr: s.expr.as_deref(),
+        footage: None,
+        property_overrides: &[],
+        media_overrides: &[],
+    };
     Ok(json!({"effect": uid, "warning": effectcraft_effects::warning(g, &mut |pr| ctx.value(layer, pr))}))
 }
 
@@ -160,7 +169,16 @@ fn pick_color(s: &mut Session, p: &Value) -> Result<Value> {
     .filter(|pr| pr.ui == effectcraft_project::ParamUi::Color)
     .ok_or_else(|| bad(cmd, "not a colour parameter of this effect"))?;
     let t = super::time_p(s, p, Some(comp));
-    let ctx = effectcraft_render::EvalCtx { project: &s.project, comp_id: cid, comp, time: t, expr: s.expr.as_deref(), footage: None };
+    let ctx = effectcraft_render::EvalCtx {
+        project: &s.project,
+        comp_id: cid,
+        comp,
+        time: t,
+        expr: s.expr.as_deref(),
+        footage: None,
+        property_overrides: &[],
+        media_overrides: &[],
+    };
     let mut r = effectcraft_render::Renderer::new(&s.project, &*s.footage, effectcraft_render::RenderOpts::default());
     r.expr = s.expr.as_deref();
     r.cache = Some(&s.layer_cache);
@@ -288,7 +306,16 @@ impl CryptoProbe {
             let comp = r.project.comp(cid).ok_or("no composition")?;
             let layer = comp.layer(lid).ok_or("no such layer")?;
             let g = layer.effects().and_then(|fx| fx.groups().nth(pos)).ok_or("no such effect")?;
-            let ctx = effectcraft_render::EvalCtx { project: r.project, comp_id: cid, comp, time, expr: r.expr, footage: None };
+            let ctx = effectcraft_render::EvalCtx {
+                project: r.project,
+                comp_id: cid,
+                comp,
+                time,
+                expr: r.expr,
+                footage: None,
+                property_overrides: &[],
+                media_overrides: &[],
+            };
             let params = effectcraft_effects::flatten_params(g, &mut |pr| ctx.value(layer, pr));
             let want = effectcraft_effects::CRYPTO_LAYERS.get(params.e("layer") as usize).copied().unwrap_or("CryptoAsset");
             let aux = r.layer_aux(&ctx, layer).ok_or(NO_CRYPTO)?;
@@ -351,7 +378,16 @@ fn probe_key<'a>(s: &'a Session, p: &Value, cmd: &str) -> Result<(ProbeKey, Tick
     let g = fx.groups().nth(pos).ok_or_else(|| bad(cmd, "no such effect"))?;
     let prop = g.prop("selection").filter(|_| g.match_id == "ec.3d.cryptomatte").ok_or_else(|| bad(cmd, "not a Cryptomatte effect"))?;
     let time = super::time_p(s, p, Some(comp));
-    let ctx = effectcraft_render::EvalCtx { project: &s.project, comp_id: cid, comp, time, expr: s.expr.as_deref(), footage: None };
+    let ctx = effectcraft_render::EvalCtx {
+        project: &s.project,
+        comp_id: cid,
+        comp,
+        time,
+        expr: s.expr.as_deref(),
+        footage: None,
+        property_overrides: &[],
+        media_overrides: &[],
+    };
     let frame = probe_frame(&ctx, layer, pos);
     let o = s.render_opts(Default::default());
     let prefs = (o.nested_switches, o.draft_shadows);
@@ -503,7 +539,16 @@ fn crypto_hit(s: &Session, p: &Value, cmd: &str) -> Result<Hit> {
     let Some(hash) = b.aux.index_at(ax, ay).and_then(|i| b.aux.crypto_id_at(&b.layer, i)) else { return Ok(Hit::Nothing) };
     let (cid, lid, ..) = key.at;
     let comp = s.project.comp(cid).ok_or(EngineError::NoComp)?;
-    let ctx = effectcraft_render::EvalCtx { project: &s.project, comp_id: cid, comp, time, expr: s.expr.as_deref(), footage: None };
+    let ctx = effectcraft_render::EvalCtx {
+        project: &s.project,
+        comp_id: cid,
+        comp,
+        time,
+        expr: s.expr.as_deref(),
+        footage: None,
+        property_overrides: &[],
+        media_overrides: &[],
+    };
     let selection = effectcraft_effects::flatten_params(g, &mut |pr| ctx.value(layer, pr)).s("selection").to_string();
     let driven = prop.expr.as_ref().is_some_and(|e| e.enabled);
     let (aux, layer_name) = (b.aux.clone(), b.layer.clone());

crates/engine/src/cmd/expr_tools.rs

@@ -163,6 +163,8 @@ pub fn language_menu() -> Vec<(&'static str, Vec<(&'static str, &'static str)>)>
                 ("easeIn(t, tMin, tMax, value1, value2)", "easeIn(t, tMin, tMax, value1, value2)"),
                 ("easeOut(t, value1, value2)", "easeOut(t, value1, value2)"),
                 ("easeOut(t, tMin, tMax, value1, value2)", "easeOut(t, tMin, tMax, value1, value2)"),
+                ("bezier(t, value1, value2, [x1, y1, x2, y2])", "bezier(t, value1, value2, [x1, y1, x2, y2])"),
+                ("bezier(t, tMin, tMax, value1, value2, [x1, y1, x2, y2])", "bezier(t, tMin, tMax, value1, value2, [x1, y1, x2, y2])"),
             ],
         ),
         (

crates/engine/src/cmd/file.rs

@@ -87,7 +87,8 @@ pub(crate) fn open(s: &mut Session, p: &Value) -> Result<Value> {
 /// project opened from an XML copy saves as XML again). Fails, writing nothing, when the project
 /// wouldn't read back.
 pub(crate) fn file_text(s: &Session, path: &str) -> Result<String> {
-    let json = s.project.to_file_json_with_view(&s.saved_view())?;
+    let compact = s.prefs.project.compact_project_files && !crate::xml_project::is_xml_path(path);
+    let json = s.project.to_file_json_with_view(&s.saved_view(), compact)?;
     if crate::xml_project::is_xml_path(path) { crate::xml_project::to_xml(&json).map_err(EngineError::Other) } else { Ok(json) }
 }
 
@@ -124,7 +125,8 @@ fn revert(s: &mut Session, _: &Value) -> Result<Value> {
 }
 
 /// File ▸ Import; with `addToComp` (files dropped on the Timeline or the Composition viewer) they
-/// also become layers of the active comp ([`add_to_comp`]).
+/// also become layers of the active comp ([`add_to_comp`]); with `newComp` (the empty viewer's
+/// New Composition From Footage) they become one new composition instead ([`new_comp`]).
 ///
 /// With `background` (files dropped on the window or picked in the Import dialog) the files are
 /// probed on a background thread, so decoding a slow video doesn't freeze the app: the job shows
@@ -174,10 +176,10 @@ fn import_cmd(s: &mut Session, p: &Value) -> Result<Value> {
     Ok(r)
 }
 
-/// After an import (its result `r`): with `addToComp`, the new items become layers of `target`;
-/// what couldn't be added joins the result's errors.
+/// After an import (its result `r`): with `newComp`, the new items become one new composition;
+/// otherwise with `addToComp`, layers of `target`. What couldn't be added joins the result's errors.
 fn finish_import(s: &mut Session, r: &mut Value, target: Option<ItemId>, p: &Value) {
-    let errors = add_to_comp(s, r, target, p);
+    let errors = if b_p(p, "newComp").unwrap_or(false) { new_comp(s, r) } else { add_to_comp(s, r, target, p) };
     if !errors.is_empty()
         && let Some(e) = r.get_mut("errors").and_then(Value::as_array_mut)
     {
@@ -191,18 +193,7 @@ fn finish_import(s: &mut Session, r: &mut Value, target: Option<ItemId>, p: &Val
 /// Project panel) and the other footage. `target` stays open. Returns what couldn't be added.
 pub(crate) fn add_to_comp(s: &mut Session, r: &Value, target: Option<ItemId>, p: &Value) -> Vec<String> {
     let Some(cid) = target.filter(|_| p.get("addToComp").and_then(Value::as_bool).unwrap_or(false)) else { return vec![] };
-    let ids = |k: &str| r.get(k).and_then(Value::as_array).into_iter().flatten().filter_map(Value::as_u64).collect::<Vec<u64>>();
-    let comps = ids("comps");
-    let in_comps: std::collections::HashSet<u64> = comps
-        .iter()
-        .filter_map(|c| s.project.comp(ItemId(*c)))
-        .flat_map(|c| c.layers.iter())
-        .filter_map(|l| match l.source {
-            LayerSource::Footage { item } | LayerSource::Comp { item } | LayerSource::Solid { item } => Some(item.0),
-            _ => None,
-        })
-        .collect();
-    let add: Vec<u64> = comps.iter().copied().chain(ids("items").into_iter().filter(|i| !in_comps.contains(i))).collect();
+    let add = imported(s, r);
     let mut errors = vec![];
     for (k, item) in add.into_iter().enumerate() {
         let mut params = json!({"comp": cid.0, "item": item, "time": p.get("time"), "position": p.get("position")});
@@ -219,6 +210,55 @@ pub(crate) fn add_to_comp(s: &mut Session, r: &Value, target: Option<ItemId>, p:
     errors
 }
 
+/// What an import (its result `r`) made that belongs in a comp: the comps of layered files
+/// (their layers' footage, in their precomps too, stays in the Project panel), then the other items,
+/// without those comps again or the files' folders.
+fn imported(s: &Session, r: &Value) -> Vec<u64> {
+    let ids = |k: &str| r.get(k).and_then(Value::as_array).into_iter().flatten().filter_map(Value::as_u64).collect::<Vec<u64>>();
+    let comps = ids("comps");
+    let mut in_comps = std::collections::HashSet::new();
+    let mut todo = comps.clone();
+    while let Some(c) = todo.pop() {
+        for l in s.project.comp(ItemId(c)).into_iter().flat_map(|c| c.layers.iter()) {
+            match l.source {
+                LayerSource::Comp { item } if in_comps.insert(item.0) => todo.push(item.0),
+                LayerSource::Footage { item } | LayerSource::Solid { item } => {
+                    in_comps.insert(item.0);
+                }
+                _ => {}
+            }
+        }
+    }
+    let rest = ids("items").into_iter().filter(|i| !in_comps.contains(i) && !comps.contains(i) && !s.project.item(ItemId(*i)).is_some_and(|it| it.is_folder()));
+    comps.iter().copied().chain(rest).collect()
+}
+
+/// With `newComp`, make one composition of the footage and solids an import (its result `r`)
+/// made, as New Comp from Selection does with `single` (first item on top, its settings). A comp
+/// the import made (a layered file) already is the composition, so it stays out, as does data
+/// footage; none left, no new comp. Returns what went wrong.
+fn new_comp(s: &mut Session, r: &Value) -> Vec<String> {
+    let items: Vec<ItemId> = imported(s, r)
+        .into_iter()
+        .map(ItemId)
+        .filter(|i| {
+            s.project.item(*i).is_some_and(|it| match &it.kind {
+                ItemKind::Footage(f) => f.kind != FootageKind::Data,
+                ItemKind::Solid(_) => true,
+                ItemKind::Comp(_) | ItemKind::Folder => false,
+            })
+        })
+        .collect();
+    if items.is_empty() {
+        return vec![];
+    }
+    s.state.project_selection = items;
+    match s.execute("file.newCompFromSelection", json!({"single": true})) {
+        Ok(_) => vec![],
+        Err(e) => vec![e.to_string()],
+    }
+}
+
 /// File ▸ Import, all in one go (scripts and commands built on it); see [`import_cmd`].
 pub(crate) fn import(s: &mut Session, p: &Value) -> Result<Value> {
     let pending = prepare_import(s, p)?;
@@ -745,7 +785,7 @@ pub fn specs() -> Vec<CommandSpec> {
             "File...",
             ["File", "Import"],
             Some("Cmd+I"),
-            "{paths: [string] (files or folders), sequence?: bool (the Sequence checkbox: true imports numbered stills of one run as one image sequence, one picked file bringing its whole run and several picked files that range; default: a numbered still brings its run, except dropped files (drag), which import as stills as in After Effects; folders' runs import as sequences; false imports stills and a folder's files individually), alphabetical?: bool (Force Alphabetical Order: every image of that type in the folder, by name), frameRate?: fps (image sequences; default Settings ▸ Import ▸ Sequence Footage), importAs?: footage|composition|compositionLayerSizes (Photoshop, PDF, Illustrator and EPS files), layer?: name|index (footage of one Photoshop layer), page?: number from 1 (PDF / Illustrator page), drag?: bool (dropped files: Settings ▸ Import ▸ Default Drag Import As; files import as stills unless sequence), addToComp?: bool (also add them to the active comp, at time?, index?, position? as in layer.addItem), background?: bool (probe the files in a background job, jobs.list / jobs.wait; returns {job})}",
+            "{paths: [string] (files or folders), sequence?: bool (the Sequence checkbox: true imports numbered stills of one run as one image sequence, one picked file bringing its whole run and several picked files that range; default false: picked or dropped files import as stills, as in After Effects; folders' runs import as sequences; false imports stills and a folder's files individually), alphabetical?: bool (Force Alphabetical Order: every image of that type in the folder, by name), frameRate?: fps (image sequences; default Settings ▸ Import ▸ Sequence Footage), importAs?: footage|composition|compositionLayerSizes (Photoshop, PDF, Illustrator and EPS files), layer?: name|index (footage of one Photoshop layer), page?: number from 1 (PDF / Illustrator page), drag?: bool (dropped files: Settings ▸ Import ▸ Default Drag Import As; files import as stills unless sequence), addToComp?: bool (also add them to the active comp, at time?, index?, position? as in layer.addItem), newComp?: bool (make one new composition of the footage and solids imported, as file.newCompFromSelection with single; a layered file imported as a composition is that composition and gets no other; takes precedence over addToComp), background?: bool (probe the files in a background job, jobs.list / jobs.wait; returns {job})}",
             always,
             import_cmd
         ),

crates/engine/src/cmd/file_more.rs

@@ -5,7 +5,7 @@
 use std::collections::{BTreeMap, BTreeSet};
 
 use effectcraft_color::Label;
-use effectcraft_project::{AlphaMode, Comp, Footage, FootageKind, ItemId, ItemKind, LayerSource, Project, Solid, limits};
+use effectcraft_project::{AlphaMode, CineonSettings, CineonUnits, Comp, Footage, FootageKind, ItemId, ItemKind, LayerSource, Project, Solid, limits};
 use effectcraft_time::{FrameRate, Tick};
 use serde_json::{Value, json};
 
@@ -501,7 +501,7 @@ fn run_script(s: &mut Session, p: &Value) -> Result<Value> {
             }
             _ => return Err(bad("file.runScript", format!("step {}: needs `command`", i + 1))),
         };
-        if id == "file.runScript" || id == "script.run" {
+        if super::scripts::RUNS_SCRIPTS.contains(&id.as_str()) {
             return Err(bad("file.runScript", "scripts can't run scripts"));
         }
         let r = if from_file { s.execute_for_script(&id, params) } else { s.execute(&id, params) };
@@ -536,7 +536,7 @@ fn is_jsxbin(name: &str) -> bool {
 }
 
 /// A script error becomes a toast and a command error.
-fn report_js(s: &mut Session, name: &str, out: Value) -> Result<Value> {
+pub(crate) fn report_js(s: &mut Session, name: &str, out: Value) -> Result<Value> {
     if let Some(e) = out.get("error").filter(|e| !e.is_null()) {
         let line = e.get("line").and_then(Value::as_u64).map(|l| format!(" (line {l})")).unwrap_or_default();
         let msg = e.get("message").and_then(Value::as_str).unwrap_or("script error");
@@ -552,6 +552,13 @@ pub(crate) fn run_js_named(s: &mut Session, code: &str, name: &str) -> Result<Va
     report_js(s, name, out)
 }
 
+/// Run the code of the script file at `path` (its `#include`s and `$.fileName` use that path),
+/// reported under its file name `name` (Startup and Shutdown scripts).
+pub(crate) fn run_js_file(s: &mut Session, code: &str, path: &str, name: &str) -> Result<Value> {
+    let out = run_js(s, code, path, false)?;
+    report_js(s, name, out)
+}
+
 /// Run JavaScript through the session's scripting engine.
 fn run_js(s: &mut Session, code: &str, name: &str, console: bool) -> Result<Value> {
     let runner = s.script.ok_or_else(|| EngineError::Other("JavaScript scripting is not available in this build".into()))?;
@@ -594,6 +601,131 @@ pub(crate) struct Interpretation {
     preserve_rgb: Option<bool>,
     /// Start Timecode.
     start: Option<StartTimecode>,
+    /// Cineon Settings (DPX and Cineon footage).
+    cineon: CineonEdit,
+}
+
+/// Interpret Footage ▸ Cineon Settings parsed from command parameters (every field optional).
+#[derive(Clone, Debug, Default)]
+struct CineonEdit {
+    /// Logarithmic Conversion.
+    log: Option<bool>,
+    units: Option<CineonUnits>,
+    /// The units the Converted Black and White Points are given in (`pointUnits`, else `cineonUnits`,
+    /// else the footage's own Units).
+    point_units: Option<CineonUnits>,
+    converted_black: Option<f64>,
+    converted_white: Option<f64>,
+    /// 10 Bit Black and White Points.
+    black: Option<f64>,
+    white: Option<f64>,
+    gamma: Option<f64>,
+    rolloff: Option<f64>,
+}
+
+impl CineonEdit {
+    fn parse(p: &Value, cmd: &str) -> Result<CineonEdit> {
+        let units = |key: &str| -> Result<Option<CineonUnits>> {
+            match str_p(p, key) {
+                None => Ok(None),
+                Some(u) => CineonUnits::parse(u).map(Some).ok_or_else(|| bad(cmd, format!("{key}: 10bit|8bit|float, not `{u}`"))),
+            }
+        };
+        let num = |key: &str, lo: f64, hi: f64| -> Result<Option<f64>> {
+            match p.get(key) {
+                None | Some(Value::Null) => Ok(None),
+                Some(v) => v
+                    .as_f64()
+                    .filter(|x| x.is_finite() && (lo..=hi).contains(x))
+                    .map(Some)
+                    .ok_or_else(|| bad(cmd, format!("{key}: a number from {lo} to {hi}"))),
+            }
+        };
+        let units_now = units("cineonUnits")?;
+        Ok(CineonEdit {
+            log: b_p(p, "logConversion"),
+            units: units_now,
+            point_units: units("pointUnits")?.or(units_now),
+            // Range-checked once their units are known (`settings_for`).
+            converted_black: num("convertedBlack", f64::MIN, f64::MAX)?,
+            converted_white: num("convertedWhite", f64::MIN, f64::MAX)?,
+            black: num("tenBitBlack", 0.0, 1023.0)?,
+            white: num("tenBitWhite", 0.0, 1023.0)?,
+            gamma: num("currentGamma", 0.1, 10.0)?,
+            rolloff: num("highlightRolloff", 0.0, 100.0)?,
+        })
+    }
+
+    fn is_empty(&self) -> bool {
+        self.log.is_none()
+            && self.units.is_none()
+            && self.converted_black.is_none()
+            && self.converted_white.is_none()
+            && self.black.is_none()
+            && self.white.is_none()
+            && self.gamma.is_none()
+            && self.rolloff.is_none()
+    }
+
+    /// Footage `f`'s Cineon Settings after this edit; `None` when nothing changes them (no Cineon
+    /// parameters, or `f` is not a DPX or Cineon file).
+    fn settings_for(&self, f: &Footage, cmd: &str) -> Result<Option<CineonSettings>> {
+        if self.is_empty() || !f.is_cineon_file() {
+            return Ok(None);
+        }
+        let mut c = f.cineon;
+        let units = self.point_units.unwrap_or(c.units);
+        let point = |v: f64| -> Result<f32> {
+            let ten = units.to_ten_bit(v);
+            let max = units.from_ten_bit(f64::from(CineonSettings::MAX));
+            if (0.0..=f64::from(CineonSettings::MAX)).contains(&ten) {
+                Ok(ten as f32)
+            } else {
+                Err(bad(cmd, format!("converted points: 0 to {max} in {} units", units.label())))
+            }
+        };
+        if let Some(v) = self.converted_black {
+            c.converted_black = point(v)?;
+        }
+        if let Some(v) = self.converted_white {
+            c.converted_white = point(v)?;
+        }
+        if let Some(v) = self.log {
+            c.log_conversion = v;
+        }
+        if let Some(u) = self.units {
+            c.units = u;
+        }
+        if let Some(v) = self.black {
+            c.black = v as f32;
+        }
+        if let Some(v) = self.white {
+            c.white = v as f32;
+        }
+        if let Some(v) = self.gamma {
+            c.gamma = v as f32;
+        }
+        if let Some(v) = self.rolloff {
+            c.rolloff = v as f32;
+        }
+        if c.black >= c.white {
+            return Err(bad(cmd, "the 10 Bit Black Point must be below the 10 Bit White Point"));
+        }
+        Ok(Some(c))
+    }
+}
+
+/// Footage `f`'s Cineon Settings as commands report them (`null` for files they don't apply to).
+fn cineon_json(f: &Footage) -> Value {
+    if !f.is_cineon_file() {
+        return Value::Null;
+    }
+    let c = &f.cineon;
+    json!({
+        "logConversion": c.log_conversion, "units": c.units.id(),
+        "convertedBlack": c.units.from_ten_bit(f64::from(c.converted_black)), "convertedWhite": c.units.from_ten_bit(f64::from(c.converted_white)),
+        "tenBitBlack": c.black, "tenBitWhite": c.white, "currentGamma": c.gamma, "highlightRolloff": c.rolloff,
+    })
 }
 
 /// Interpret Footage ▸ Start Timecode.
@@ -687,9 +819,23 @@ impl Interpretation {
                 v.as_f64().filter(|x| x.is_finite() && (0.0..=StartTimecode::MAX as f64).contains(x)).map(|x| x.round() as i64).ok_or_else(start_err)?,
             )),
         };
+        it.cineon = CineonEdit::parse(p, cmd)?;
         Ok(it)
     }
 
+    /// Check the Cineon Settings this interpretation gives each of `footage`: an error names a
+    /// value out of range, or Cineon parameters when none of the footage is DPX or Cineon.
+    pub(crate) fn check<'a>(&self, footage: impl IntoIterator<Item = &'a Footage>, cmd: &str) -> Result<()> {
+        if self.cineon.is_empty() {
+            return Ok(());
+        }
+        let mut any = false;
+        for f in footage {
+            any |= self.cineon.settings_for(f, cmd)?.is_some();
+        }
+        if any { Ok(()) } else { Err(bad(cmd, "Cineon Settings apply to DPX and Cineon footage only")) }
+    }
+
     pub(crate) fn apply(&self, f: &mut Footage, guessed: Option<(AlphaMode, [f32; 3])>) {
         let before = f.frame_rate;
         self.apply_settings(f, guessed);
@@ -749,6 +895,10 @@ impl Interpretation {
         if let Some(v) = self.preserve_rgb {
             f.preserve_rgb = v;
         }
+        // Checked before the edit (`Interpretation::check`).
+        if let Ok(Some(c)) = self.cineon.settings_for(f, "file.interpretFootage") {
+            f.cineon = c;
+        }
         // After the frame rate: timecode is read at the footage's rate.
         if let Some(start) = self.start.as_ref().and_then(|t| t.frame(f.frame_rate)) {
             f.start_timecode = start;
@@ -795,6 +945,11 @@ fn interpret(s: &mut Session, p: &Value) -> Result<Value> {
         return Err(bad("file.interpretFootage", "select footage"));
     }
     let it = Interpretation::parse(p, "file.interpretFootage")?;
+    let footage = items.iter().filter_map(|i| match s.project.item(*i).map(|x| &x.kind) {
+        Some(ItemKind::Footage(f)) => Some(f),
+        _ => None,
+    });
+    it.check(footage, "file.interpretFootage")?;
     let guesses: Vec<Option<(AlphaMode, [f32; 3])>> = items
         .iter()
         .map(|i| match (it.guess, s.project.item(*i).map(|x| &x.kind)) {
@@ -830,7 +985,7 @@ fn interpret(s: &mut Session, p: &Value) -> Result<Value> {
                 "item": i.0, "alpha": format!("{:?}", f.alpha), "matteColor": f.premul_color, "invertAlpha": f.invert_alpha,
                 "fields": f.fields.label(), "pixelAspect": f.pixel_aspect, "loop": f.loop_count, "frameRate": f.frame_rate.as_f64(),
                 "linearLight": f.linear_light, "preserveRgb": f.preserve_rgb, "startTimecode": f.timecode(0), "overrideStart": f.start_timecode.is_some(),
-                "frames": f.sequence_frames(),
+                "frames": f.sequence_frames(), "cineon": cineon_json(f),
             })),
             _ => None,
         })
@@ -861,6 +1016,9 @@ fn apply_interpretation(s: &mut Session, p: &Value) -> Result<Value> {
                 f.linear_light = src.linear_light;
                 f.preserve_rgb = src.preserve_rgb;
                 f.color_profile = src.color_profile;
+                if f.is_cineon_file() && src.is_cineon_file() {
+                    f.cineon = src.cineon;
+                }
                 if src.native_rate.is_some() {
                     if f.native_rate.is_none() {
                         f.native_rate = Some(f.frame_rate);
@@ -878,10 +1036,34 @@ fn replace_footage(s: &mut Session, p: &Value) -> Result<Value> {
     let path = str_p(p, "path").ok_or_else(|| bad("file.replaceFootage", "missing `path`"))?.to_string();
     let item = *items_p(s, p).first().ok_or_else(|| bad("file.replaceFootage", "select footage"))?;
     let importer = s.importer.clone().ok_or_else(|| EngineError::Other("media import is not available in this build".into()))?;
-    // A numbered still brings its image sequence, as on import (`sequence: false` for one frame).
-    let opts = SequenceOptions::from_params(p);
+    // Replacing a still keeps it a still; replacing a sequence keeps bringing the new file's run.
+    // `sequence`/`alphabetical` override that (#2073).
+    let previous = match s.project.item(item).map(|it| &it.kind) {
+        Some(ItemKind::Footage(f)) if f.kind == FootageKind::Sequence => (true, true, f.alphabetical),
+        _ => (false, false, false),
+    };
+    // Only `sequence` decides whether the item keeps its kind; `alphabetical` is a sequence
+    // modifier, not a request to make one.
+    let inherited = b_p(p, "sequence").is_none();
+    let mut opts = SequenceOptions::from_params(p);
+    if inherited {
+        (opts.sequence, opts.folders) = (previous.0, previous.1);
+        if previous.0 && b_p(p, "alphabetical").is_none() {
+            opts.alphabetical = previous.2;
+        }
+    }
     let src = crate::sequence::source_of(s.services.as_ref(), &path, opts);
-    let f = crate::sequence::probe(importer.as_ref(), &src, s.sequence_rate()).map_err(|e| EngineError::Other(format!("{path}: {e}")))?;
+    let mut f = crate::sequence::probe(importer.as_ref(), &src, s.sequence_rate()).map_err(|e| EngineError::Other(format!("{path}: {e}")))?;
+    // A single-file source comes back as a still; an inherited sequence kind keeps it a
+    // one-frame sequence, so a later default replacement still brings numbered runs (#2073).
+    if inherited && previous.0 && matches!(src, crate::sequence::Source::File(_)) && f.kind == FootageKind::Still {
+        f.kind = FootageKind::Sequence;
+        f.sequence = vec![f.path.clone()];
+        f.alphabetical = opts.alphabetical;
+        f.frame_rate = s.sequence_rate();
+        f.native_rate = None;
+        f.sync_sequence_duration();
+    }
     let name = src.name();
     // Replacing a missing file relinks the other missing files that moved with it (as After Effects
     // does when you locate one).
@@ -1066,7 +1248,7 @@ pub fn specs() -> Vec<CommandSpec> {
             "Main...",
             ["File", "Interpret Footage"],
             Some("Cmd+Alt+G"),
-            "{items?|item?, frameRate?: fps|\"file\", alpha?: straight|premultiplied|ignore|guess, guessAlpha?, matteColor?|premulColor?, invertAlpha?, loop?, pixelAspect?, fields?: off|upper|lower, colorProfile?: srgb|rec709|rec2020|p3|auto, linearLight?, preserveRgb? (the file's values unconverted), overrideStart?: bool (false: Use Source File Timecode), startTimecode?: timecode|frame (Override Start)}",
+            "{items?|item?, frameRate?: fps|\"file\", alpha?: straight|premultiplied|ignore|guess, guessAlpha?, matteColor?|premulColor?, invertAlpha?, loop?, pixelAspect?, fields?: off|upper|lower, colorProfile?: srgb|rec709|rec2020|p3|auto, linearLight?, preserveRgb? (the file's values unconverted), overrideStart?: bool (false: Use Source File Timecode), startTimecode?: timecode|frame (Override Start), logConversion? (Cineon Settings of DPX and Cineon files), cineonUnits?: 10bit|8bit|float, convertedBlack?, convertedWhite?, pointUnits?: 10bit|8bit|float (the units of convertedBlack and convertedWhite; default cineonUnits, else the footage's Units), tenBitBlack?, tenBitWhite? (0..1023), currentGamma? (0.1..10), highlightRolloff? (0..100)}",
             has_footage_selection,
             interpret
         ),
@@ -1093,7 +1275,7 @@ pub fn specs() -> Vec<CommandSpec> {
             "File...",
             ["File", "Replace Footage"],
             Some("Cmd+H"),
-            "{path, item?, sequence?: bool (default true: a numbered still brings its image sequence), alphabetical?: bool}",
+            "{path, item?, sequence?: bool (a numbered still brings its image sequence; default: the item keeps its kind, so a still stays a still and a sequence stays a sequence), alphabetical?: bool}",
             has_footage_selection,
             replace_footage
         ),

crates/engine/src/cmd/focus.rs

@@ -78,6 +78,12 @@ fn set_to_layer(s: &mut Session, p: &Value) -> Result<Value> {
     let c = "camera.setFocusToLayer";
     let (cid, cam, target) = refs(s, p, c, true)?;
     let d = focus_depth(s, cid, cam, target.ok_or_else(|| bad(c, "no layer"))?).ok_or_else(|| bad(c, "can't evaluate the layers"))?;
+    // Only a finite depth can be stored: JSON has no infinity or NaN, so the project could no
+    // longer be saved. Extreme but finite positions can still produce one, and `d <= 0.0` is
+    // false for NaN.
+    if !d.is_finite() {
+        return Err(bad(c, "can't measure the distance to the layer (the camera or layer position is out of range)"));
+    }
     if d <= 0.0 {
         return Err(bad(c, "the layer is behind the camera"));
     }

crates/engine/src/cmd/footage_panel.rs

@@ -56,6 +56,12 @@ pub fn timecode(item: Option<&effectcraft_project::Item>, fr: effectcraft_time::
     }
 }
 
+/// The frame the Footage panel shows: footage `f` at source time `t`, with its Cineon Settings
+/// applied.
+pub fn frame(s: &Session, item: ItemId, f: &effectcraft_project::Footage, t: Tick) -> Option<std::sync::Arc<effectcraft_raster::Image>> {
+    s.footage.frame(item, f, t).map(|img| effectcraft_render::cineon_frame(img, f))
+}
+
 fn source_time(s: &Session, p: &Value, item: ItemId) -> Option<Tick> {
     let (_, fr) = source_timing(s, item);
     if let Some(t) = f_p(p, "time") {

crates/engine/src/cmd/layer.rs

@@ -48,7 +48,7 @@ pub fn specs() -> Vec<CommandSpec> {
             "Text",
             ["Layer", "New"],
             Some("Cmd+Alt+Shift+T"),
-            "{text?, name? (layer name; default the text), position? [x,y], box? [x,y,w,h] (paragraph text, comp space), vertical?, edit? (start editing), font?, style?, size?, fill?, stroke?, applyFill?, applyStroke?, strokeWidth?, tracking?, leading?, baselineShift?, hScale?, vScale?, tsume?, fauxBold?, fauxItalic?, allCaps?, smallCaps?, baseline?, superscript?, subscript?, kerning?, ligatures?, justify?, indentLeft?, indentRight?, indentFirst?, spaceBefore?, spaceAfter?, direction?, composer?, hangingPunctuation?, strokeOverFill?} (attributes as layer.setText)",
+            "{text?, name? (layer name; default the text), position? [x,y], box? [x,y,w,h] (paragraph text, comp space), vertical?, edit? (start editing), font?, style?, size?, fill?, stroke?, applyFill?, applyStroke?, strokeWidth?, tracking?, leading?, baselineShift?, hScale?, vScale?, tsume?, fauxBold?, fauxItalic?, allCaps?, smallCaps?, baseline?, superscript?, subscript?, kerning?, ligatures?, justify?, indentLeft?, indentRight?, indentFirst?, spaceBefore?, spaceAfter?, direction?, composer?, hangingPunctuation?, strokeOverFill?, lineJoin?} (attributes as layer.setText)",
             has_comp,
             new_text
         ),
@@ -121,7 +121,7 @@ pub fn specs() -> Vec<CommandSpec> {
             "Track Matte",
             [],
             None,
-            "{layer?, matte: layer|null, kind?: alpha|alphaInverted|luma|lumaInverted}",
+            "{layers? | layer?, matte: layer|null, kind?: alpha|alphaInverted|luma|lumaInverted|preserve}",
             has_layers,
             track_matte
         ),
@@ -183,7 +183,7 @@ pub fn specs() -> Vec<CommandSpec> {
             "Add (Shape)",
             [],
             None,
-            "{layer?, kind: group|rect|ellipse|star|polygon|path|fill|stroke|gfill|gstroke|trim|repeater|round|offset|pucker|twist|zigzag|wiggle|merge|frontColor|bevelColor|sideColor|backColor, group?: uid|path} → {uid, path} (frontColor…backColor: the group's Front / Bevel / Side / Back item, which colours that surface of every extruded paint in the group in Advanced 3D)",
+            "{layer?, kind: group|rect|ellipse|star|polygon|path|fill|stroke|gfill|gstroke|trim|repeater|round|offset|pucker|twist|zigzag|wiggle|wiggler|merge|frontColor|bevelColor|sideColor|backColor, group?: uid|path} → {uid, path} (frontColor…backColor: the group's Front / Bevel / Side / Back item, which colours that surface of every extruded paint in the group in Advanced 3D)",
             has_layers,
             add_shape_item
         ),
@@ -192,7 +192,7 @@ pub fn specs() -> Vec<CommandSpec> {
             "Edit Text",
             [],
             None,
-            "{layer?, range?: [start, end] (characters; default all), text?, font?, style?, size?, fill?, stroke?, applyFill?, applyStroke?, strokeWidth?, tracking?, leading?: px|\"auto\", baselineShift? px, hScale? %, vScale? %, tsume? %, fauxBold?, fauxItalic?, allCaps?, smallCaps?, baseline?: normal|superscript|subscript, superscript?, subscript?, kerning?: metrics|optical|number, ligatures?, discretionaryLigatures? (OpenType), contextualAlternates?, stylisticAlternates?, stylisticSets?: [1–20], ss01?, ss02?, ss03?, ss04?, ss05?, ss06?, ss07?, ss08?, ss09?, ss10?, ss11?, ss12?, ss13?, ss14?, ss15?, ss16?, ss17?, ss18?, ss19?, ss20?, swash?, titling?, ordinals?, fractions?, allSmallCaps?, figureStyle?: default|lining|oldStyle, figureWidth?: default|proportional|tabular, figures?, variations?: {tag: value} (variable font axes; null resets), justify?: left|center|right|justifyLeft|justifyCenter|justifyRight|justifyAll, indentLeft?, indentRight?, indentFirst?, spaceBefore?, spaceAfter?, direction?: ltr|rtl, composer?: everyLine|singleLine, hangingPunctuation?, strokeOverFill?, box?: [x,y,w,h]|null (layer space), vertical?}",
+            "{layer?, range?: [start, end] (characters; default all), text?, font?, style?, size?, fill?, stroke?, applyFill?, applyStroke?, strokeWidth?, tracking?, leading?: px|\"auto\", baselineShift? px, hScale? %, vScale? %, tsume? %, fauxBold?, fauxItalic?, allCaps?, smallCaps?, baseline?: normal|superscript|subscript, superscript?, subscript?, kerning?: metrics|optical|number, ligatures?, discretionaryLigatures? (OpenType), contextualAlternates?, stylisticAlternates?, stylisticSets?: [1–20], ss01?, ss02?, ss03?, ss04?, ss05?, ss06?, ss07?, ss08?, ss09?, ss10?, ss11?, ss12?, ss13?, ss14?, ss15?, ss16?, ss17?, ss18?, ss19?, ss20?, swash?, titling?, ordinals?, fractions?, allSmallCaps?, figureStyle?: default|lining|oldStyle, figureWidth?: default|proportional|tabular, figures?, variations?: {tag: value} (variable font axes; null resets), justify?: left|center|right|justifyLeft|justifyCenter|justifyRight|justifyAll, indentLeft?, indentRight?, indentFirst?, spaceBefore?, spaceAfter?, direction?: ltr|rtl, composer?: everyLine|singleLine, hangingPunctuation?, strokeOverFill?, lineJoin?: miter|round|bevel, box?: [x,y,w,h]|null (layer space), vertical?}",
             has_layers,
             set_text
         ),

crates/engine/src/cmd/layer/create.rs

@@ -161,7 +161,7 @@ pub(super) fn text_range_p(p: &Value) -> Option<std::ops::Range<usize>> {
 /// It is left justified unless `justify` is given. The layer is named by `name`, else the first 40
 /// characters of the first text line, else "Text". `edit: true` also opens a new editing
 /// session with anchor `0` and the caret after the text, selecting all initial text so the next
-/// insertion replaces it. The session has `created: true`, so leaving it empty removes the layer.
+/// insertion replaces it. The session has `created: true`; leaving it empty keeps the layer, as After Effects does.
 pub(super) fn new_text(s: &mut Session, p: &Value) -> Result<Value> {
     let cid = comp_id(s, p)?;
     let comp = s.project.comp(cid).ok_or(EngineError::NoComp)?.clone();

crates/engine/src/cmd/layer/parent.rs

@@ -1,4 +1,4 @@
-use super::{Comp, EngineError, ItemId, KV, Layer, LayerId, PropGroup, Result, Session, Tick, Value, b_p, bad, layers_p, resolve_layer};
+use super::{Comp, EngineError, ItemId, KV, Layer, LayerId, PropGroup, Result, Session, Tick, Value, b_p, bad, layers_p, resolve_layer, unlocked};
 
 /// Re-express a layer in its new parent space without moving its anchor.
 pub(crate) struct ParentFix {
@@ -9,10 +9,20 @@ pub(crate) struct ParentFix {
     rotation: f64,
     /// Multiply Scale.
     scale: [f64; 2],
-    /// 3D AV layers retain their world-space anchor, including Z.
+    /// 3D AV layers retain their world-space anchor, including Z. Cameras and lights also
+    /// re-express their Point of Interest.
     position_3d: Option<effectcraft_geom::Mat4>,
-    /// A uniform relative parent transform can preserve static Orientation and Scale.
-    pose_3d: Option<([f64; 3], f64)>,
+    /// A uniform relative parent transform re-expresses static Orientation and Scale.
+    pose_3d: Option<Pose3d>,
+}
+
+/// A uniform relative parent transform, as it applies to a 3D layer's Orientation and Scale.
+#[derive(Clone, Copy)]
+struct Pose3d {
+    /// Rotation that Orientation is re-expressed under: `Orientation' = correction * Orientation`.
+    correction: effectcraft_geom::Mat4,
+    /// Uniform scale factor, multiplied into Scale (negative for a mirrored parent).
+    factor: f64,
 }
 
 impl ParentFix {
@@ -22,7 +32,7 @@ impl ParentFix {
         if let Some(m) = self.position_3d {
             // Spatial Position speed measures distance along its path. Its parent-space
             // unit changes even when the child's Orientation cannot be re-expressed.
-            let position_speed = uniform_parent_pose(m, [0.0; 3]).map(|(_, factor)| factor.abs());
+            let position_speed = uniform_rotation(m).map(|(_, factor)| factor.abs());
             let map_position = |v: &KV| {
                 let q = m.apply(effectcraft_geom::Vec3::from(v.as_vec3()));
                 KV::Vec3([q.x, q.y, q.z])
@@ -44,7 +54,8 @@ impl ParentFix {
                     }
                 }
             }
-            if let Some(pr) = tr.get_mut("position") {
+            // Position and a camera's or light's Point of Interest are both points in the parent's space.
+            let map_point = |pr: &mut effectcraft_project::Property| {
                 pr.value = map_position(&pr.value);
                 for key in &mut pr.keys {
                     key.value = map_position(&key.value);
@@ -64,34 +75,19 @@ impl ParentFix {
                         }
                     }
                 }
+            };
+            if let Some(pr) = tr.get_mut("position") {
+                map_point(pr);
             }
-            // Cameras and lights aim with Point of Interest: move it by the same parent-space
-            // change, so a two-node rig keeps its world frame (#1010, #1020).
             if let Some(pr) = tr.get_mut("poi") {
-                pr.value = map_position(&pr.value);
-                for key in &mut pr.keys {
-                    key.value = map_position(&key.value);
-                    for tangent in [&mut key.spatial_in, &mut key.spatial_out] {
-                        let v = m.apply_vec(effectcraft_geom::Vec3::from(*tangent));
-                        *tangent = [v.x, v.y, v.z];
-                    }
-                }
-                if let Some(factor) = position_speed
-                    .filter(|_| pr.spatial)
-                    .filter(|factor| pr.keys.iter().flat_map(|key| key.in_ease.iter().chain(&key.out_ease)).all(|ease| (ease.speed * *factor).is_finite()))
-                {
-                    for key in &mut pr.keys {
-                        for ease in key.in_ease.iter_mut().chain(&mut key.out_ease) {
-                            ease.speed *= factor;
-                        }
-                    }
-                }
+                map_point(pr);
             }
-            if let Some((orientation, factor)) = self.pose_3d {
+            if let Some(pose) = self.pose_3d {
                 if let Some(pr) = tr.get_mut("orientation") {
-                    pr.value = KV::Vec3(orientation);
+                    reexpress_orientation(pose.correction, pr);
                 }
                 if let Some(pr) = tr.get_mut("scale") {
+                    let factor = pose.factor;
                     let scaled = |value: &KV| KV::Vec3(value.as_vec3().map(|v| v * factor));
                     pr.value = scaled(&pr.value);
                     for key in &mut pr.keys {
@@ -154,13 +150,10 @@ impl ParentFix {
     }
 }
 
-/// A uniform factor commutes with authored axis Rotation and Scale; prepend its orthogonal
-/// rotation to static Orientation using the existing Rz * Ry * Rx order.
-fn uniform_parent_pose(m: effectcraft_geom::Mat4, orientation: [f64; 3]) -> Option<([f64; 3], f64)> {
-    use effectcraft_geom::{Mat4, Vec3, vec3};
-    if !orientation.iter().all(|v| v.is_finite()) {
-        return None;
-    }
+/// The rotation and signed scale factor of a uniform parent transform's linear part (negative for a
+/// mirrored parent). `None` for a non-uniform or degenerate transform.
+fn uniform_rotation(m: effectcraft_geom::Mat4) -> Option<(effectcraft_geom::Mat4, f64)> {
+    use effectcraft_geom::{Mat4, vec3};
     let a = m.0;
     let columns = [vec3(a[0][0], a[1][0], a[2][0]), vec3(a[0][1], a[1][1], a[2][1]), vec3(a[0][2], a[1][2], a[2][2])];
     let magnitude = columns[0].x.hypot(columns[0].y).hypot(columns[0].z);
@@ -179,15 +172,188 @@ fn uniform_parent_pose(m: effectcraft_geom::Mat4, orientation: [f64; 3]) -> Opti
             rotation.0[row][col] = a[row][col] / factor;
         }
     }
-    if (0..3).all(|row| (0..3).all(|col| (rotation.0[row][col] - if row == col { 1.0 } else { 0.0 }).abs() < 1e-12)) {
-        return Some((orientation, factor));
-    }
-    let r = (rotation * Mat4::orientation(Vec3::from(orientation))).0;
+    Some((rotation, factor))
+}
+
+/// The turn (degrees) of a rotation about Z alone, or `None` for any other rotation.
+fn z_only_turn(correction: effectcraft_geom::Mat4) -> Option<f64> {
+    let m = correction.0;
+    let about_z = [m[0][2], m[1][2], m[2][0], m[2][1]].iter().all(|v| v.abs() < 1e-9) && (m[2][2] - 1.0).abs() < 1e-9;
+    about_z.then(|| m[1][0].atan2(m[0][0]).to_degrees())
+}
+
+/// ZYX Euler angles in degrees of a row-major rotation (`Rz * Ry * Rx`), safe at gimbal lock.
+fn euler_zyx(r: [[f64; 4]; 4]) -> [f64; 3] {
     // atan2 rather than asin: near ±90 degrees asin loses precision, while cos(y) stays exact.
     let cy = r[0][0].hypot(r[1][0]);
     let y = (-r[2][0]).atan2(cy);
     let (x, z) = if cy > 1e-9 { (r[2][1].atan2(r[2][2]), r[1][0].atan2(r[0][0])) } else { ((-r[1][2]).atan2(r[1][1]), 0.0) };
-    Some(([x.to_degrees(), y.to_degrees(), z.to_degrees()], factor))
+    [x.to_degrees(), y.to_degrees(), z.to_degrees()]
+}
+
+/// The equivalent ZYX Euler triple nearest `reference`: each axis moved by whole turns, or the
+/// `(x + 180, 180 - y, z + 180)` form when that is nearer.
+fn nearest_euler(euler: [f64; 3], reference: [f64; 3]) -> [f64; 3] {
+    let near = |v: [f64; 3]| -> [f64; 3] { std::array::from_fn(|i| v[i] + ((reference[i] - v[i]) / 360.0).round() * 360.0) };
+    let natural = near(euler);
+    let flipped = near([euler[0] + 180.0, 180.0 - euler[1], euler[2] + 180.0]);
+    let distance = |v: [f64; 3]| v.iter().zip(reference.iter()).map(|(a, b)| (a - b).powi(2)).sum::<f64>();
+    if distance(flipped) < distance(natural) { flipped } else { natural }
+}
+
+/// The Euler Orientation of `correction * Orientation(o)`, in the form nearest `reference`.
+fn reexpress_euler(correction: effectcraft_geom::Mat4, o: [f64; 3], reference: [f64; 3]) -> [f64; 3] {
+    let world = correction * effectcraft_geom::Mat4::orientation(effectcraft_geom::Vec3::from(o));
+    nearest_euler(euler_zyx(world.0), reference)
+}
+
+/// Largest angle (degrees) a baked Orientation may drift from the exact rotation between its keys.
+const BAKE_TOLERANCE_DEGREES: f64 = 0.05;
+/// How many times a segment may be halved while baking, and the most keys a property may end up with.
+const BAKE_MAX_DEPTH: u32 = 10;
+const BAKE_MAX_KEYS: usize = 4096;
+
+/// The angle (degrees) between two rotations.
+fn rotation_angle(a: effectcraft_geom::Mat4, b: effectcraft_geom::Mat4) -> f64 {
+    let trace: f64 = (0..3).flat_map(|i| (0..3).map(move |j| (i, j))).map(|(i, j)| a.0[i][j] * b.0[i][j]).sum();
+    ((trace - 1.0) / 2.0).clamp(-1.0, 1.0).acos().to_degrees()
+}
+
+/// Adds keys between `(ta, ea)` and `(tb, eb)` (already converted) wherever the straight Euler blend
+/// between them drifts from `correction * Orientation(authored)` by more than the tolerance. `out`
+/// never grows past `budget` keys: what the whole property may still add, not what one segment may.
+fn bake_between(
+    correction: effectcraft_geom::Mat4,
+    authored: &effectcraft_project::Property,
+    (ta, ea): (Tick, [f64; 3]),
+    (tb, eb): (Tick, [f64; 3]),
+    depth: u32,
+    budget: usize,
+    out: &mut Vec<effectcraft_keyframe::Keyframe>,
+) {
+    use effectcraft_geom::{Mat4, Vec3};
+    if depth == 0 || tb.0 - ta.0 < 2 || out.len() >= budget {
+        return;
+    }
+    let tm = Tick(ta.0 + (tb.0 - ta.0) / 2);
+    let blend = [(ea[0] + eb[0]) / 2.0, (ea[1] + eb[1]) / 2.0, (ea[2] + eb[2]) / 2.0];
+    let exact = correction * Mat4::orientation(Vec3::from(authored.value_at(tm).as_vec3()));
+    // Symmetric easing crosses the straight blend at its midpoint. Check both sides too before
+    // accepting a segment whose original easing will be replaced with a linear blend.
+    let quarter = (tb.0 - ta.0) / 4;
+    if [Tick(ta.0 + quarter), tm, Tick(tb.0 - quarter)].into_iter().all(|t| {
+        let u = (t.0 - ta.0) as f64 / (tb.0 - ta.0) as f64;
+        let linear = std::array::from_fn(|i| ea[i] + (eb[i] - ea[i]) * u);
+        let target = correction * Mat4::orientation(Vec3::from(authored.value_at(t).as_vec3()));
+        rotation_angle(Mat4::orientation(Vec3::from(linear)), target) <= BAKE_TOLERANCE_DEGREES
+    }) {
+        return;
+    }
+    let em = nearest_euler(euler_zyx(exact.0), blend);
+    bake_between(correction, authored, (ta, ea), (tm, em), depth - 1, budget, out);
+    if out.len() >= budget {
+        return;
+    }
+    out.push(effectcraft_keyframe::Keyframe::new(tm, KV::Vec3(em)));
+    bake_between(correction, authored, (tm, em), (tb, eb), depth - 1, budget, out);
+}
+
+/// Re-expresses Orientation as `correction * Orientation`. A Z-only correction shifts Z exactly in the
+/// value and every key. For any other correction a static value is converted directly; keys are
+/// converted, and keys are added between them wherever the Euler blend between two keys would drift
+/// from the exact rotation (the segments become linear, with the original easing baked in).
+fn reexpress_orientation(correction: effectcraft_geom::Mat4, pr: &mut effectcraft_project::Property) {
+    if let Some(turn) = z_only_turn(correction) {
+        // No turn (an identity correction) leaves every authored value as it is.
+        if turn.abs() <= 1e-12 {
+            return;
+        }
+        let shift = |value: &KV| {
+            let [x, y, z] = value.as_vec3();
+            KV::Vec3([x, y, z + turn])
+        };
+        pr.value = shift(&pr.value);
+        for key in &mut pr.keys {
+            key.value = shift(&key.value);
+        }
+        return;
+    }
+    let value = pr.value.as_vec3();
+    pr.value = KV::Vec3(reexpress_euler(correction, value, value));
+    if pr.keys.is_empty() {
+        return;
+    }
+    let authored = pr.clone();
+    // Each key keeps the authored change from the previous key on top of its converted value.
+    let mut converted: Vec<[f64; 3]> = vec![];
+    let mut prev: Option<([f64; 3], [f64; 3])> = None;
+    for key in &authored.keys {
+        let o = key.value.as_vec3();
+        let reference = match prev {
+            Some((before, after)) => [after[0] + o[0] - before[0], after[1] + o[1] - before[1], after[2] + o[2] - before[2]],
+            None => o,
+        };
+        let n = reexpress_euler(correction, o, reference);
+        converted.push(n);
+        prev = Some((o, n));
+    }
+    use effectcraft_keyframe::Interp;
+    let mut keys: Vec<effectcraft_keyframe::Keyframe> = vec![];
+    let mut after_baked_segment = false;
+    for (i, key) in authored.keys.iter().enumerate() {
+        let mut k = key.clone();
+        k.value = KV::Vec3(converted[i]);
+        if after_baked_segment {
+            k.in_interp = Interp::Linear;
+            k.in_ease.clear();
+            k.auto_bezier = false;
+            k.continuous = false;
+        }
+        after_baked_segment = false;
+        let segment = authored.keys.get(i + 1).filter(|_| key.out_interp != Interp::Hold);
+        let mut between = vec![];
+        if let Some(next) = segment {
+            // What the whole property may still add: the keys it will have already (the ones written
+            // and the authored ones still to come) count against the cap.
+            let budget = BAKE_MAX_KEYS.saturating_sub(keys.len() + authored.keys.len() - i);
+            bake_between(correction, &authored, (key.time, converted[i]), (next.time, converted[i + 1]), BAKE_MAX_DEPTH, budget, &mut between);
+            // With the cap reached the segment can't be checked or subdivided: it keeps its authored easing between
+            // the converted keys, rather than becoming a straight blend that was never checked against the original.
+            if between.len() >= budget {
+                between.clear();
+            // An eased segment, or one that gained keys, becomes a run of straight blends.
+            } else if !between.is_empty() || key.out_interp != Interp::Linear || next.in_interp != Interp::Linear {
+                k.out_interp = Interp::Linear;
+                k.out_ease.clear();
+                k.auto_bezier = false;
+                k.continuous = false;
+                after_baked_segment = true;
+            }
+        }
+        keys.push(k);
+        keys.extend(between);
+    }
+    pr.keys = keys;
+}
+
+/// Correction for a two-node rig's Orientation: after a uniform parent change its aim is
+/// `rotation * aim`, so the roll is re-expressed against that aim. `None` for a degenerate aim.
+fn aim_correction(rotation: effectcraft_geom::Mat4, aim: [f64; 3]) -> Option<effectcraft_geom::Mat4> {
+    use effectcraft_geom::vec3;
+    use effectcraft_render::three_d::camera::basis_rotation;
+    let [x, y, z] = aim;
+    let length = (x * x + y * y + z * z).sqrt();
+    if !length.is_finite() || length <= 1e-9 {
+        return None;
+    }
+    let dir = vec3(x / length, y / length, z / length);
+    let turned = rotation.apply_vec(dir);
+    // A view along the up axis has no roll to keep, and its basis is undefined.
+    if 1.0 - dir.y * dir.y < 1e-12 || 1.0 - turned.y * turned.y < 1e-12 {
+        return None;
+    }
+    let up = vec3(0.0, 1.0, 0.0);
+    Some(basis_rotation(turned, up).transpose() * rotation * basis_rotation(dir, up))
 }
 
 /// A parent change retains 2D transforms and the world-space anchor of 3D layers (Position,
@@ -196,8 +362,16 @@ fn uniform_parent_pose(m: effectcraft_geom::Mat4, orientation: [f64; 3]) -> Opti
 /// time.
 pub(crate) fn parent_fixes(s: &Session, cid: ItemId, ids: &[LayerId], parent: Option<LayerId>) -> Vec<ParentFix> {
     let Some(comp) = s.project.comp(cid) else { return vec![] };
-    let ectx =
-        effectcraft_render::EvalCtx { project: &s.project, comp_id: cid, comp, time: s.time(), expr: s.expr.as_deref(), footage: Some(s.footage.as_ref()) };
+    let ectx = effectcraft_render::EvalCtx {
+        project: &s.project,
+        comp_id: cid,
+        comp,
+        time: s.time(),
+        expr: s.expr.as_deref(),
+        footage: Some(s.footage.as_ref()),
+        property_overrides: &[],
+        media_overrides: &[],
+    };
     let space = |id: Option<LayerId>| -> effectcraft_geom::Mat3 {
         id.and_then(|i| comp.layer(i)).filter(|l| !l.is_3d()).map(|l| ectx.layer_to_comp(l).0).unwrap_or(effectcraft_geom::Mat3::IDENTITY)
     };
@@ -235,31 +409,58 @@ pub(crate) fn parent_fixes(s: &Session, cid: ItemId, ids: &[LayerId], parent: Op
         })
     };
     if let Some(inv) = space_3d(parent).inverse().filter(|m| m.0.iter().flatten().all(|v| v.is_finite())) {
-        // Cameras and lights compensate like 3D layers (Position, and Point of Interest for
-        // two-node rigs), so parenting keeps the world frame (#1010, #1020). They have no
-        // Scale, so `pose_3d` below stays `None` and Orientation is kept as authored.
         for layer in comp.layers.iter().filter(|l| ids.contains(&l.id) && l.is_3d() && l.parent != parent) {
             let m = inv * space_3d(layer.parent);
+            // A one-node camera or light has no Scale to carry a mirror, and its frame (forward and
+            // down) would come out reversed: compensate none of it, so Position and Orientation stay
+            // as authored instead of half-following the parent.
+            let rig = layer.is_camera() || layer.is_light();
+            if rig && !effectcraft_render::three_d::camera::is_two_node(layer) && uniform_rotation(m).is_some_and(|(_, factor)| factor <= 0.0) {
+                continue;
+            }
             if m.0.iter().flatten().all(|v| v.is_finite()) {
                 let pose_3d = layer.transform().and_then(|tr| {
                     let orientation = tr.get("orientation")?;
-                    let scale = tr.get("scale")?;
-                    // Animated Euler Orientation and auto-orient cannot be re-expressed by
-                    // prepending a constant Euler value. Expression-driven values stay authored.
-                    if !orientation.keys.is_empty()
-                        || orientation.expr.is_some()
-                        || scale.expr.is_some()
-                        || layer.auto_orient != effectcraft_project::AutoOrient::Off
+                    // Cameras and lights have no Scale; their Orientation is re-expressed alone.
+                    let scale = tr.get("scale");
+                    // Expression-driven values stay authored. Auto-orient replaces Orientation, except
+                    // a two-node rig, whose roll is re-expressed against its new aim.
+                    let two_node = (layer.is_camera() || layer.is_light()) && effectcraft_render::three_d::camera::is_two_node(layer);
+                    if orientation.expr.is_some()
+                        || scale.is_some_and(|scale| scale.expr.is_some())
+                        || (layer.auto_orient != effectcraft_project::AutoOrient::Off && !two_node)
                     {
                         return None;
                     }
-                    let pose = uniform_parent_pose(m, orientation.value.as_vec3())?;
-                    let factor = pose.1;
-                    let values_finite = std::iter::once(&scale.value)
-                        .chain(scale.keys.iter().map(|key| &key.value))
-                        .all(|value| value.as_vec3().iter().all(|v| (v * factor).is_finite()));
-                    let speeds_finite = scale.keys.iter().flat_map(|key| key.in_ease.iter().chain(&key.out_ease)).all(|ease| (ease.speed * factor).is_finite());
-                    (values_finite && speeds_finite).then_some(pose)
+                    let (rotation, factor) = uniform_rotation(m)?;
+                    let correction = if two_node {
+                        // A mirrored parent flips the aim, which this correction does not model.
+                        if factor <= 0.0 {
+                            return None;
+                        }
+                        let (w, h) = (comp.width as f64, comp.height as f64);
+                        let pos = ectx.v3(layer, tr, "position", [w / 2.0, h / 2.0, -1000.0]);
+                        let poi = ectx.v3(layer, tr, "poi", [w / 2.0, h / 2.0, 0.0]);
+                        aim_correction(rotation, [poi[0] - pos[0], poi[1] - pos[1], poi[2] - pos[2]])?
+                    } else {
+                        rotation
+                    };
+                    let orientation_finite = std::iter::once(&orientation.value)
+                        .chain(orientation.keys.iter().map(|key| &key.value))
+                        .all(|value| value.as_vec3().iter().all(|v| v.is_finite()));
+                    if !correction.0.iter().flatten().all(|v| v.is_finite()) || !orientation_finite {
+                        return None;
+                    }
+                    if let Some(scale) = scale {
+                        let values_finite = std::iter::once(&scale.value)
+                            .chain(scale.keys.iter().map(|key| &key.value))
+                            .all(|value| value.as_vec3().iter().all(|v| (v * factor).is_finite()));
+                        let speeds_finite = scale.keys.iter().all(|key| key.in_ease.iter().chain(&key.out_ease).all(|ease| (ease.speed * factor).is_finite()));
+                        if !values_finite || !speeds_finite {
+                            return None;
+                        }
+                    }
+                    Some(Pose3d { correction, factor })
                 });
                 fixes.push(ParentFix { layer: layer.id, m: effectcraft_geom::Mat3::IDENTITY, rotation: 0.0, scale: [1.0; 2], position_3d: Some(m), pose_3d });
             }
@@ -309,6 +510,8 @@ fn check_parent_chain(comp: &Comp, ids: &[LayerId], parent: Option<LayerId>, max
 
 pub(super) fn set_parent(s: &mut Session, p: &Value) -> Result<Value> {
     let (cid, ids) = layers_p(s, p)?;
+    // Locked layers keep their parent (several at once: the others are parented).
+    let ids = unlocked(s, cid, ids, "layer.setParent")?;
     let comp = s.project.comp(cid).ok_or(EngineError::NoComp)?;
     let parent = match p.get("parent") {
         None | Some(Value::Null) => None,
@@ -323,7 +526,7 @@ pub(super) fn set_parent(s: &mut Session, p: &Value) -> Result<Value> {
     let fixes = if compensate { parent_fixes(s, cid, &ids, parent) } else { vec![] };
     s.edit("Parent", None, |proj, _| {
         let comp = proj.comp_mut(cid).ok_or(EngineError::NoComp)?;
-        for l in comp.layers.iter_mut().filter(|l| ids.contains(&l.id)) {
+        for l in comp.layers.iter_mut_where(|l| ids.contains(&l.id)) {
             l.parent = parent;
             if let Some(f) = fixes.iter().find(|f| f.layer == l.id) {
                 f.apply(l);

crates/engine/src/cmd/layer/switches.rs

@@ -1,6 +1,6 @@
 use super::{
     BlendMode, EngineError, FrameBlend, ItemId, KV, Layer, LayerId, MatteKind, Quality, Result, Session, TrackMatte, Value, b_p, bad, json, layer_mut, layer_p,
-    layers_p, merge_p, resolve_layer, str_p,
+    layers_p, merge_p, resolve_layer, str_p, unlocked,
 };
 
 pub(super) fn set_switch(s: &mut Session, p: &Value) -> Result<Value> {
@@ -19,7 +19,7 @@ pub(super) fn set_switch(s: &mut Session, p: &Value) -> Result<Value> {
         let first = comp.layers.iter().find(|l| ids.contains(&l.id)).map(|l| switch_value(l, &name)).unwrap_or(Some(false));
         let Some(first) = first else { return Err(bad("layer.setSwitch", format!("unknown switch `{name}`"))) };
         let target = v.unwrap_or(!first);
-        for l in comp.layers.iter_mut().filter(|l| ids.contains(&l.id)) {
+        for l in comp.layers.iter_mut_where(|l| ids.contains(&l.id)) {
             set_switch_value(l, &name, target);
             last = target;
         }
@@ -55,7 +55,7 @@ fn set_switch_others(s: &mut Session, cid: ItemId, ids: &[LayerId], name: &str,
             alone &= on == (ids.contains(&l.id) == active);
         }
         let others = value.unwrap_or(alone == active);
-        for l in comp.layers.iter_mut().filter(|l| applies(l)) {
+        for l in comp.layers.iter_mut_where(|l| applies(l)) {
             let v = if ids.contains(&l.id) { active } else { others };
             set_switch_value(l, name, v);
         }
@@ -152,7 +152,7 @@ pub(super) fn set_comment(s: &mut Session, p: &Value) -> Result<Value> {
     let text = str_p(p, "comment").ok_or_else(|| bad("layer.setComment", "missing `comment`"))?.to_string();
     s.edit("Layer Comment", None, |proj, _| {
         let comp = proj.comp_mut(cid).ok_or(EngineError::NoComp)?;
-        for l in comp.layers.iter_mut().filter(|l| ids.contains(&l.id)) {
+        for l in comp.layers.iter_mut_where(|l| ids.contains(&l.id)) {
             l.comment = text.clone();
         }
         Ok(())
@@ -169,7 +169,7 @@ pub(super) fn blend(s: &mut Session, p: &Value) -> Result<Value> {
     }
     s.edit("Blending Mode", None, |proj, _| {
         let comp = proj.comp_mut(cid).ok_or(EngineError::NoComp)?;
-        for l in comp.layers.iter_mut().filter(|l| ids.contains(&l.id)) {
+        for l in comp.layers.iter_mut_where(|l| ids.contains(&l.id)) {
             l.blend_mode = match mode {
                 Some(m) => m,
                 None if step > 0 => l.blend_mode.next(),
@@ -181,33 +181,122 @@ pub(super) fn blend(s: &mut Session, p: &Value) -> Result<Value> {
     Ok(Value::Null)
 }
 
+/// `layer.setTrackMatte`: `layers` (or `layer`, else the first selected layer; locked ones left
+/// as they are) use `matte` as their track matte (none when null), in one undo step. `kind` sets the mode; `preserve` keeps
+/// each layer's own (Alpha for a layer without a matte), so changing the matte of several layers
+/// at once keeps their modes.
 pub(super) fn track_matte(s: &mut Session, p: &Value) -> Result<Value> {
-    let (cid, lid) = layer_p(s, p, "layer.setTrackMatte")?;
+    let (cid, ids) = match p.get("layers") {
+        Some(_) => layers_p(s, p)?,
+        None => layer_p(s, p, "layer.setTrackMatte").map(|(c, l)| (c, vec![l]))?,
+    };
+    // Locked layers keep their matte (several at once: the others get it).
+    let ids = unlocked(s, cid, ids, "layer.setTrackMatte")?;
     let comp = s.project.comp(cid).ok_or(EngineError::NoComp)?;
     let matte = match p.get("matte") {
         None | Some(Value::Null) => None,
         Some(v) => Some(resolve_layer(comp, v).ok_or_else(|| bad("layer.setTrackMatte", "no such matte layer"))?),
     };
-    let kind = str_p(p, "kind")
-        .map(|k| match k.to_ascii_lowercase().replace([' ', '_', '-'], "").as_str() {
+    if ids.is_empty() {
+        return Err(bad("layer.setTrackMatte", "no layers"));
+    }
+    if matte.is_some_and(|m| ids.contains(&m)) {
+        return Err(bad("layer.setTrackMatte", "a layer can't be its own matte"));
+    }
+    // None: each layer keeps its own mode.
+    let kind = match str_p(p, "kind").map(|k| k.to_ascii_lowercase().replace([' ', '_', '-'], "")) {
+        Some(k) if k == "preserve" => None,
+        Some(k) => Some(match k.as_str() {
             "alphainverted" | "alphainv" => MatteKind::AlphaInverted,
             "luma" => MatteKind::Luma,
             "lumainverted" | "lumainv" => MatteKind::LumaInverted,
             _ => MatteKind::Alpha,
-        })
-        .unwrap_or(MatteKind::Alpha);
+        }),
+        None => Some(MatteKind::Alpha),
+    };
     s.edit("Track Matte", None, |proj, _| {
         let comp = proj.comp_mut(cid).ok_or(EngineError::NoComp)?;
-        if let Some(m) = matte {
-            if m == lid {
-                return Err(bad("layer.setTrackMatte", "a layer can't be its own matte"));
-            }
-            if let Some(ml) = comp.layer_mut(m) {
-                ml.switches.video = false;
-            }
+        if let Some(ml) = matte.and_then(|m| comp.layer_mut(m)) {
+            ml.switches.video = false;
+        }
+        for lid in &ids {
+            let l = comp.layer_mut(*lid).ok_or(EngineError::NoComp)?;
+            let kind = kind.unwrap_or_else(|| l.track_matte.map(|m| m.kind).unwrap_or_default());
+            l.track_matte = matte.map(|layer| TrackMatte { layer, kind });
         }
-        comp.layer_mut(lid).ok_or(EngineError::NoComp)?.track_matte = matte.map(|layer| TrackMatte { layer, kind });
         Ok(())
     })?;
     Ok(Value::Null)
 }
+
+#[cfg(test)]
+mod track_matte_batch_tests {
+    use super::*;
+    use std::sync::Arc;
+
+    fn matte_of(s: &Session, id: u64) -> Option<(u64, MatteKind)> {
+        s.active_comp().unwrap().layer(LayerId(id)).unwrap().track_matte.map(|m| (m.layer.0, m.kind))
+    }
+
+    /// #1260: several layers take one matte layer at once, in one undo step; `kind: "preserve"`
+    /// keeps each one's mode; refused calls change nothing; one `layer` still works.
+    #[test]
+    fn several_layers_take_one_matte_and_keep_their_modes() {
+        let mut s = Session::default();
+        s.execute("comp.new", json!({"name":"Mattes","width":16,"height":16,"duration":1})).unwrap();
+        let [a, b, c, x, y] = ["A", "B", "C", "X", "Y"].map(|n| s.execute("layer.newSolid", json!({"name": n})).unwrap()["layer"].as_u64().unwrap());
+        s.execute("layer.setTrackMatte", json!({"layer": a, "matte": x, "kind": "luma"})).unwrap();
+        s.execute("layer.setTrackMatte", json!({"layer": b, "matte": x})).unwrap();
+        assert_eq!((matte_of(&s, a), matte_of(&s, b)), (Some((x, MatteKind::Luma)), Some((x, MatteKind::Alpha))), "one layer, as before");
+        let (before, undo) = (s.project.clone(), s.history.undo.len());
+        s.execute("layer.setTrackMatte", json!({"layers": [a, b, c], "matte": y, "kind": "preserve"})).unwrap();
+        assert_eq!(
+            [matte_of(&s, a), matte_of(&s, b), matte_of(&s, c)],
+            [Some((y, MatteKind::Luma)), Some((y, MatteKind::Alpha)), Some((y, MatteKind::Alpha))],
+            "each keeps its mode (Alpha without one)"
+        );
+        assert!(!s.active_comp().unwrap().layer(LayerId(y)).unwrap().switches.video, "the matte is hidden");
+        assert_eq!(s.history.undo.len(), undo + 1, "one undo step");
+        s.execute("edit.undo", json!({})).unwrap();
+        assert!(s.project.same_content(&before));
+        // Refused: a layer as its own matte, an unknown layer, no layers. Nothing changes.
+        for p in [
+            json!({"layers": [a, y], "matte": y}),
+            json!({"layers": [a, 9999], "matte": y}),
+            json!({"layers": [], "matte": y}),
+            json!({"layers": [a], "matte": 9999}),
+        ] {
+            let (project, revision) = (s.project.clone(), s.revision);
+            assert!(s.execute("layer.setTrackMatte", p.clone()).is_err(), "{p}");
+            assert!(Arc::ptr_eq(&project, &s.project) && s.revision == revision, "{p} changed nothing");
+        }
+        s.execute("layer.setTrackMatte", json!({"layers": [a, b], "matte": null})).unwrap();
+        assert_eq!((matte_of(&s, a), matte_of(&s, b)), (None, None), "both lose it");
+    }
+
+    /// Locked layers keep their parent and matte when they are among several (the others change),
+    /// and alone they are an error that changes nothing.
+    #[test]
+    fn locked_layers_keep_their_parent_and_matte() {
+        let mut s = Session::default();
+        s.execute("comp.new", json!({"name":"Locks","width":16,"height":16,"duration":1})).unwrap();
+        let [a, b, p, m] = ["A", "B", "P", "M"].map(|n| s.execute("layer.newSolid", json!({"name": n})).unwrap()["layer"].as_u64().unwrap());
+        s.execute("layer.setSwitch", json!({"layers": [b], "switch": "lock", "value": true})).unwrap();
+        let layer = |s: &Session, id: u64| s.active_comp().unwrap().layer(LayerId(id)).unwrap().clone();
+        s.execute("layer.setParent", json!({"layers": [a, b], "parent": p})).unwrap();
+        s.execute("layer.setTrackMatte", json!({"layers": [a, b], "matte": m, "kind": "preserve"})).unwrap();
+        s.execute("layer.trackMatte", json!({"layers": [a, b], "op": "luma"})).unwrap();
+        assert_eq!((layer(&s, a).parent, matte_of(&s, a)), (Some(LayerId(p)), Some((m, MatteKind::Luma))));
+        assert_eq!((layer(&s, b).parent, matte_of(&s, b)), (None, None), "the locked layer is left as it was");
+        for (cmd, p) in [
+            ("layer.setParent", json!({"layers": [b], "parent": p})),
+            ("layer.setTrackMatte", json!({"layers": [b], "matte": m})),
+            ("layer.trackMatte", json!({"layers": [b], "op": "alpha"})),
+        ] {
+            let (project, revision) = (s.project.clone(), s.revision);
+            let err = s.execute(cmd, p).unwrap_err();
+            assert!(err.to_string().contains("is locked"), "{cmd}: {err}");
+            assert!(Arc::ptr_eq(&project, &s.project) && s.revision == revision, "{cmd} changed nothing");
+        }
+    }
+}

crates/engine/src/cmd/layer/timing.rs

@@ -18,7 +18,7 @@ pub(super) fn timing(s: &mut Session, p: &Value) -> Result<Value> {
         let comp = proj.comp_mut(cid).ok_or(EngineError::NoComp)?;
         let fd = comp.frame_duration();
         let comp_dur = comp.duration;
-        for l in comp.layers.iter_mut().filter(|l| ids.contains(&l.id)) {
+        for l in comp.layers.iter_mut_where(|l| ids.contains(&l.id)) {
             let shift = |l: &mut Layer, d: Tick| {
                 l.start_time += d;
                 l.in_point += d;
@@ -42,7 +42,9 @@ pub(super) fn timing(s: &mut Session, p: &Value) -> Result<Value> {
                     shift(l, d);
                 }
                 "trimInToTime" => l.in_point = t.min(l.out_point - fd),
-                "trimOutToTime" => l.out_point = t.max(l.in_point + fd),
+                // Alt+]: the Out edge lands one frame after the playhead, so its frame stays the
+                // layer's last visible one (as in After Effects), never before the In point.
+                "trimOutToTime" => l.out_point = t.max(l.in_point) + fd,
                 _ => {
                     if let Some(d) = delta {
                         shift(l, d);
@@ -159,14 +161,14 @@ pub(super) fn arrange(s: &mut Session, p: &Value) -> Result<Value> {
                 for i in 1..n {
                     if picked(&comp.layers[i]) && !picked(&comp.layers[i - 1]) {
                         let run_end = (i..n).find(|j| !picked(&comp.layers[*j])).unwrap_or(n);
-                        comp.layers[i - 1..run_end].rotate_left(1);
+                        comp.layers.rotate_range_left(i - 1..run_end, 1);
                     }
                 }
             } else {
                 for i in (0..n.saturating_sub(1)).rev() {
                     if picked(&comp.layers[i]) && !picked(&comp.layers[i + 1]) {
                         let run_start = (0..=i).rev().find(|j| !picked(&comp.layers[*j])).map_or(0, |j| j + 1);
-                        comp.layers[run_start..=i + 1].rotate_right(1);
+                        comp.layers.rotate_range_right(run_start..=i + 1, 1);
                     }
                 }
             }

crates/engine/src/cmd/layer/transform.rs

@@ -74,14 +74,39 @@ pub(super) fn transform_op(s: &mut Session, p: &Value) -> Result<Value> {
     let op = str_p(p, "op").unwrap_or("reset").to_string();
     let comp = s.project.comp(cid).ok_or(EngineError::NoComp)?.clone();
     let t = s.time();
-    let sizes: Vec<(LayerId, (u32, u32))> =
-        comp.layers.iter().filter(|l| ids.contains(&l.id)).map(|l| (l.id, effectcraft_render::source_size(&s.project, l))).collect();
+    // A shape or text layer has no source item, so source_size is (0, 0): the fit ops size it by
+    // its painted bounds at the current time instead, and anchor at the bounds' centre — content
+    // bounds live in layer space, where a shape is centred on the origin and text sits above its
+    // baseline, so (w/2, h/2) would push it off-centre (#2198). Reset and the other ops keep the
+    // source size.
+    let ectx = effectcraft_render::EvalCtx {
+        expr: s.expr.as_deref(),
+        footage: Some(s.footage.as_ref()),
+        ..effectcraft_render::EvalCtx::new(&s.project, cid, &comp, t)
+    };
+    let fitting = matches!(op.as_str(), "fit" | "fitWidth" | "fitHeight");
+    let sizes: Vec<(LayerId, [f64; 2], [f64; 2])> = comp
+        .layers
+        .iter()
+        .filter(|l| ids.contains(&l.id))
+        .map(|l| {
+            let (w, h) = effectcraft_render::source_size(&s.project, l);
+            if fitting && (w == 0 || h == 0) {
+                match effectcraft_render::content_bounds(&ectx, l).filter(|b| b.iter().all(|v| v.is_finite()) && b[2] > b[0] && b[3] > b[1]) {
+                    Some(b) => (l.id, [b[2] - b[0], b[3] - b[1]], [(b[0] + b[2]) / 2.0, (b[1] + b[3]) / 2.0]),
+                    None => (l.id, [0.0; 2], [0.0; 2]),
+                }
+            } else {
+                (l.id, [w as f64, h as f64], [w as f64 / 2.0, h as f64 / 2.0])
+            }
+        })
+        .collect();
     s.edit("Transform", None, |proj, _| {
-        for (lid, (w, h)) in &sizes {
+        for (lid, size, anchor) in &sizes {
             let l = layer_mut(proj, cid, *lid)?;
             let lt = l.layer_time(t);
             let (cw, ch) = (comp.width as f64, comp.height as f64);
-            let (w, h) = (*w as f64, *h as f64);
+            let (w, h) = (size[0], size[1]);
             let Some(tr) = l.transform_mut() else { continue };
             let set = |tr: &mut PropGroup, m: &str, v: KV| {
                 if let Some(pr) = tr.get_mut(m) {
@@ -105,11 +130,15 @@ pub(super) fn transform_op(s: &mut Session, p: &Value) -> Result<Value> {
                         "fitHeight" => (ch / h, ch / h),
                         _ => (cw / w, ch / h),
                     };
+                    // A tiny shape's bounds can overflow the scale; refuse rather than write infinity.
+                    if !(sx * 100.0).is_finite() || !(sy * 100.0).is_finite() {
+                        return Err(EngineError::Other(format!("layer {} is too small to fit to the composition", lid.0)));
+                    }
                     let z = |m: &str, d: f64| tr.get(m).map(|p| p.value_at(lt).as_vec3()[2]).unwrap_or(d);
                     let (sz, az) = (z("scale", 100.0), z("anchor", 0.0));
                     set(tr, "scale", KV::Vec3([sx * 100.0, sy * 100.0, sz]));
                     update_position(tr, lt, |p| [cw / 2.0, ch / 2.0, p[2]]);
-                    set(tr, "anchor", KV::Vec3([w / 2.0, h / 2.0, az]));
+                    set(tr, "anchor", KV::Vec3([anchor[0], anchor[1], az]));
                 }
                 "flipH" | "flipV" => {
                     let cur = tr.get("scale").map(|p| p.value_at(lt).as_vec3()).unwrap_or([100.0; 3]);

crates/engine/src/cmd/layer_menu.rs

@@ -61,7 +61,7 @@ fn quality(s: &mut Session, p: &Value) -> Result<Value> {
         q => return Err(bad("layer.quality", format!("quality must be best|draft|wireframe, not `{q}`"))),
     };
     s.edit("Layer Quality", None, |proj, _| {
-        for l in proj.comp_mut(cid).ok_or(EngineError::NoComp)?.layers.iter_mut().filter(|l| ids.contains(&l.id)) {
+        for l in proj.comp_mut(cid).ok_or(EngineError::NoComp)?.layers.iter_mut_where(|l| ids.contains(&l.id)) {
             l.switches.quality = q;
         }
         Ok(())
@@ -84,7 +84,7 @@ fn sampling(s: &mut Session, p: &Value) -> Result<Value> {
         q => q,
     };
     s.edit("Layer Sampling", None, |proj, _| {
-        for l in proj.comp_mut(cid).ok_or(EngineError::NoComp)?.layers.iter_mut().filter(|l| ids.contains(&l.id)) {
+        for l in proj.comp_mut(cid).ok_or(EngineError::NoComp)?.layers.iter_mut_where(|l| ids.contains(&l.id)) {
             l.switches.sampling = q;
         }
         Ok(())
@@ -101,7 +101,7 @@ fn frame_blending(s: &mut Session, p: &Value) -> Result<Value> {
         m => return Err(bad("layer.frameBlending", format!("mode must be off|frameMix|pixelMotion, not `{m}`"))),
     };
     s.edit("Frame Blending", None, |proj, _| {
-        for l in proj.comp_mut(cid).ok_or(EngineError::NoComp)?.layers.iter_mut().filter(|l| ids.contains(&l.id)) {
+        for l in proj.comp_mut(cid).ok_or(EngineError::NoComp)?.layers.iter_mut_where(|l| ids.contains(&l.id)) {
             l.switches.frame_blend = m;
         }
         Ok(())
@@ -116,7 +116,7 @@ fn hide_other_video(s: &mut Session, p: &Value) -> Result<Value> {
     s.edit("Hide Other Video", None, |proj, _| {
         // Every layer has a Video switch (nulls, cameras and lights included, as the Timeline's
         // eye cell shows): the selection stays shown.
-        for l in proj.comp_mut(cid).ok_or(EngineError::NoComp)?.layers.iter_mut().filter(|l| !ids.contains(&l.id)) {
+        for l in proj.comp_mut(cid).ok_or(EngineError::NoComp)?.layers.iter_mut_where(|l| !ids.contains(&l.id)) {
             l.switches.video = false;
         }
         Ok(())
@@ -130,7 +130,7 @@ fn show_all_video(s: &mut Session, p: &Value) -> Result<Value> {
         let c = proj.comp_mut(cid).ok_or(EngineError::NoComp)?;
         // Track mattes stay hidden (their video switch is off by design).
         let mattes: Vec<LayerId> = c.layers.iter().filter_map(|l| l.track_matte.map(|m| m.layer)).collect();
-        for l in c.layers.iter_mut().filter(|l| !mattes.contains(&l.id)) {
+        for l in c.layers.iter_mut_where(|l| !mattes.contains(&l.id)) {
             l.switches.video = true;
         }
         Ok(())
@@ -154,7 +154,7 @@ fn expressions(s: &mut Session, p: &Value) -> Result<Value> {
     let on = b_p(p, "enabled").unwrap_or(true);
     let n = s.edit(if on { "Enable Expressions" } else { "Disable Expressions" }, None, |proj, _| {
         let mut n = 0;
-        for l in proj.comp_mut(cid).ok_or(EngineError::NoComp)?.layers.iter_mut().filter(|l| ids.contains(&l.id)) {
+        for l in proj.comp_mut(cid).ok_or(EngineError::NoComp)?.layers.iter_mut_where(|l| ids.contains(&l.id)) {
             l.props.walk_mut(&mut |pr| {
                 if let Some(e) = &mut pr.expr {
                     e.enabled = on;
@@ -586,7 +586,7 @@ fn markers_lock(s: &mut Session, p: &Value) -> Result<Value> {
     let r = s.edit("Lock Markers", None, |proj, _| {
         let c = proj.comp_mut(cid).ok_or(EngineError::NoComp)?;
         let target = v.unwrap_or_else(|| !c.layers.iter().find(|l| ids.contains(&l.id)).is_some_and(|l| l.markers_locked));
-        for l in c.layers.iter_mut().filter(|l| ids.contains(&l.id)) {
+        for l in c.layers.iter_mut_where(|l| ids.contains(&l.id)) {
             l.markers_locked = target;
         }
         Ok(target)
@@ -597,7 +597,7 @@ fn markers_lock(s: &mut Session, p: &Value) -> Result<Value> {
 fn delete_all_markers(s: &mut Session, p: &Value) -> Result<Value> {
     let (cid, ids) = layers_p(s, p)?;
     s.edit("Delete All Markers", None, |proj, _| {
-        for l in proj.comp_mut(cid).ok_or(EngineError::NoComp)?.layers.iter_mut().filter(|l| ids.contains(&l.id) && !l.markers_locked) {
+        for l in proj.comp_mut(cid).ok_or(EngineError::NoComp)?.layers.iter_mut_where(|l| ids.contains(&l.id) && !l.markers_locked) {
             l.markers.clear();
         }
         Ok(())
@@ -609,6 +609,7 @@ fn delete_all_markers(s: &mut Session, p: &Value) -> Result<Value> {
 
 fn track_matte_op(s: &mut Session, p: &Value) -> Result<Value> {
     let (cid, ids) = layers_p(s, p)?;
+    let ids = super::unlocked(s, cid, ids, "layer.trackMatte")?;
     let op = str_p(p, "op").ok_or_else(|| bad("layer.trackMatte", "missing `op`"))?.to_string();
     let kind = match op.as_str() {
         "alpha" => Some(MatteKind::Alpha),

crates/engine/src/cmd/layer_time.rs

@@ -34,7 +34,7 @@ fn time_stretch(s: &mut Session, p: &Value) -> Result<Value> {
     let fd = comp_rate.frame_duration();
     s.edit(if reverse { "Time-Reverse Layer" } else { "Time Stretch" }, None, |proj, _| {
         let comp = proj.comp_mut(cid).ok_or(EngineError::NoComp)?;
-        for l in comp.layers.iter_mut().filter(|l| ids.contains(&l.id)) {
+        for l in comp.layers.iter_mut_where(|l| ids.contains(&l.id)) {
             let old = l.stretch;
             if reverse {
                 // Keep the in/out points; play the visible span backwards.
@@ -109,7 +109,7 @@ fn enable_time_remap(s: &mut Session, p: &Value) -> Result<Value> {
         let mut next = proj.next_id;
         let comp = proj.comp_mut(cid).ok_or(EngineError::NoComp)?;
         let mut on = false;
-        for l in comp.layers.iter_mut().filter(|l| ids.contains(&l.id) && remappable(l)) {
+        for l in comp.layers.iter_mut_where(|l| ids.contains(&l.id) && remappable(l)) {
             let has = l.props.get("timeRemap").is_some();
             let target = want.unwrap_or(!has);
             on |= target;
@@ -185,7 +185,16 @@ fn freeze(s: &mut Session, p: &Value, last: bool) -> Result<Value> {
         return Err(bad("layer.freezeFrame", "freezing needs a footage or composition layer"));
     }
     // What each layer shows now (honouring an existing remap) — evaluated before the edit.
-    let ectx = effectcraft_render::EvalCtx { project: &s.project, comp_id: cid, comp, time: cti, expr: s.expr.as_deref(), footage: Some(s.footage.as_ref()) };
+    let ectx = effectcraft_render::EvalCtx {
+        project: &s.project,
+        comp_id: cid,
+        comp,
+        time: cti,
+        expr: s.expr.as_deref(),
+        footage: Some(s.footage.as_ref()),
+        property_overrides: &[],
+        media_overrides: &[],
+    };
     let now: Vec<(effectcraft_project::LayerId, f64)> = comp
         .layers
         .iter()

crates/engine/src/cmd/markers.rs

@@ -296,8 +296,9 @@ fn convert(s: &mut Session, p: &Value) -> Result<Value> {
     Ok(Value::Null)
 }
 
-/// Layer ▸ Markers ▸ Update Markers From Source: copy a precomp's composition markers onto the
-/// layer (layer time is the nested comp's time), skipping ones already there.
+/// Layer ▸ Markers ▸ Update Markers From Source: copy a precomp's composition markers, or the
+/// markers a footage file carries (a WAV's cue points), onto the layer (layer time is the source's
+/// time), skipping ones already there.
 fn update_from_source(s: &mut Session, p: &Value) -> Result<Value> {
     let (cid, ids) = layers_p(s, p)?;
     let src: Vec<(LayerId, Vec<Marker>)> = {
@@ -307,13 +308,17 @@ fn update_from_source(s: &mut Session, p: &Value) -> Result<Value> {
                 let l = comp.layer(*id)?;
                 match &l.source {
                     LayerSource::Comp { item } => Some((*id, s.project.comp(*item)?.markers.clone())),
+                    LayerSource::Footage { item } => match &s.project.item(*item)?.kind {
+                        effectcraft_project::ItemKind::Footage(f) => Some((*id, f.markers.clone())),
+                        _ => None,
+                    },
                     _ => None,
                 }
             })
             .collect()
     };
     if src.is_empty() {
-        return Err(bad("layer.updateMarkersFromSource", "select a precomposition layer"));
+        return Err(bad("layer.updateMarkersFromSource", "select a precomposition or footage layer"));
     }
     let n = s.edit("Update Markers From Source", None, |proj, _| {
         let c = proj.comp_mut(cid).ok_or(EngineError::NoComp)?;
@@ -323,8 +328,11 @@ fn update_from_source(s: &mut Session, p: &Value) -> Result<Value> {
             if l.markers_locked {
                 continue;
             }
+            // One set of the times already on the layer: a file with thousands of markers must not
+            // scan the layer's list for each of them.
+            let mut times: std::collections::HashSet<_> = l.markers.iter().map(|x| x.time).collect();
             for m in ms {
-                if !l.markers.iter().any(|x| x.time == m.time) {
+                if times.insert(m.time) {
                     l.markers.push(m.clone());
                     n += 1;
                 }
@@ -339,10 +347,10 @@ fn update_from_source(s: &mut Session, p: &Value) -> Result<Value> {
 fn has_precomp_layer(s: &Session) -> std::result::Result<(), String> {
     has_layers(s)?;
     let c = s.active_comp().ok_or("no composition")?;
-    if s.state.selected_layers.iter().filter_map(|l| c.layer(*l)).any(|l| matches!(l.source, LayerSource::Comp { .. })) {
+    if s.state.selected_layers.iter().filter_map(|l| c.layer(*l)).any(|l| matches!(l.source, LayerSource::Comp { .. } | LayerSource::Footage { .. })) {
         Ok(())
     } else {
-        Err("select a precomposition layer".into())
+        Err("select a precomposition or footage layer".into())
     }
 }
 

crates/engine/src/cmd/model3d.rs

@@ -64,6 +64,12 @@ fn comp_renderer(s: &mut Session, p: &Value) -> Result<Value> {
     if r == Renderer::Classic3D && s.project.comp(cid).is_some_and(|c| c.layers.iter().any(|l| l.source.is_model())) {
         s.toast("Classic 3D doesn't draw 3D model layers: they show with the Advanced 3D renderer");
     }
+    if r == Renderer::Classic3D {
+        let env = |l: &Layer| matches!(l.source, LayerSource::Light { kind: effectcraft_project::LightKind::Environment });
+        if s.project.comp(cid).is_some_and(|c| c.layers.iter().any(env)) {
+            s.toast("Classic 3D doesn't light Environment light layers: they light with the Advanced 3D renderer");
+        }
+    }
     Ok(json!({"renderer": renderer_id(r)}))
 }
 
@@ -77,7 +83,7 @@ fn renderer_id(r: Renderer) -> &'static str {
 /// Only the Advanced 3D renderer draws model and primitive layers, so adding one switches a
 /// Classic 3D comp to it, like After Effects (inside the adding edit: one undo step). Whether
 /// the renderer changed.
-fn use_advanced_3d(proj: &mut effectcraft_project::Project, cid: ItemId) -> Result<bool> {
+pub(crate) fn use_advanced_3d(proj: &mut effectcraft_project::Project, cid: ItemId) -> Result<bool> {
     let c = proj.comp_mut(cid).ok_or(EngineError::NoComp)?;
     let switched = c.renderer != Renderer::Advanced3D;
     c.renderer = Renderer::Advanced3D;
@@ -86,10 +92,10 @@ fn use_advanced_3d(proj: &mut effectcraft_project::Project, cid: ItemId) -> Resu
 }
 
 /// Tell the user when [`use_advanced_3d`] changed the comp's renderer.
-fn report_switch(s: &mut Session, cid: ItemId, switched: bool) {
+pub(crate) fn report_switch(s: &mut Session, cid: ItemId, switched: bool, why: &str) {
     if switched {
         let name = s.project.item(cid).map_or("the composition", |i| i.name.as_str()).to_string();
-        s.toast(format!("\"{name}\" now uses the Advanced 3D renderer, which draws 3D models"));
+        s.toast(format!("\"{name}\" now uses the Advanced 3D renderer, {why}"));
     }
 }
 
@@ -156,7 +162,7 @@ pub(crate) fn new_model(s: &mut Session, p: &Value) -> Result<Value> {
         let id = insert_layer_at(proj, st, cid, l, index)?;
         Ok((id, use_advanced_3d(proj, cid)?))
     })?;
-    report_switch(s, cid, switched);
+    report_switch(s, cid, switched, "which draws 3D models");
     Ok(json!({"layer": id.0, "item": item.0, "advanced3d": true}))
 }
 
@@ -226,7 +232,7 @@ fn new_primitive(s: &mut Session, p: &Value) -> Result<Value> {
         let id = insert_layer(proj, st, cid, l)?;
         Ok((id, use_advanced_3d(proj, cid)?))
     })?;
-    report_switch(s, cid, switched);
+    report_switch(s, cid, switched, "which draws 3D models");
     Ok(json!({"layer": id.0, "kind": kind.label(), "advanced3d": true}))
 }
 

crates/engine/src/cmd/path_nulls.rs

@@ -78,7 +78,16 @@ fn info(s: &Session, cid: ItemId, lid: LayerId, uid: Uid, cmd: &str) -> Result<P
     let layer = comp.layer(lid).ok_or(EngineError::NoComp)?;
     let pr = layer.props.find(uid).ok_or_else(|| bad(cmd, "no such property"))?;
     let t = s.time();
-    let ctx = effectcraft_render::EvalCtx { project: &s.project, comp_id: cid, comp, time: t, expr: s.expr.as_deref(), footage: Some(s.footage.as_ref()) };
+    let ctx = effectcraft_render::EvalCtx {
+        project: &s.project,
+        comp_id: cid,
+        comp,
+        time: t,
+        expr: s.expr.as_deref(),
+        footage: Some(s.footage.as_ref()),
+        property_overrides: &[],
+        media_overrides: &[],
+    };
     let KV::Path(path) = ctx.value(layer, pr) else { return Err(bad(cmd, "that property is not a path")) };
     if path.vertices.is_empty() {
         return Err(bad(cmd, "the path has no vertices"));
@@ -147,8 +156,16 @@ fn pin_targets(s: &Session, p: &Value, cmd: &str) -> Result<Option<(ItemId, Vec<
     };
     let cid = pins.first().map(|x| x.0).ok_or_else(|| bad(cmd, "no puppet pins"))?;
     let comp = s.project.comp(cid).ok_or(EngineError::NoComp)?;
-    let ctx =
-        effectcraft_render::EvalCtx { project: &s.project, comp_id: cid, comp, time: s.time(), expr: s.expr.as_deref(), footage: Some(s.footage.as_ref()) };
+    let ctx = effectcraft_render::EvalCtx {
+        project: &s.project,
+        comp_id: cid,
+        comp,
+        time: s.time(),
+        expr: s.expr.as_deref(),
+        footage: Some(s.footage.as_ref()),
+        property_overrides: &[],
+        media_overrides: &[],
+    };
     let mut out = vec![];
     for (_, lid, uid) in pins {
         let Some(layer) = comp.layer(lid) else { continue };

crates/engine/src/cmd/paths.rs

@@ -8,7 +8,7 @@ use effectcraft_project::{FeatherFalloff, GroupKind, ItemId, LayerId, LayerSourc
 use serde_json::{Value, json};
 
 use super::layer_menu::target_masks;
-use super::{CommandSpec, b_p, bad, f_p, has_comp, has_layers, layer_mut, layer_p, str_p};
+use super::{CommandSpec, b_p, bad, f_p, has_comp, has_layers, layer_mut, layer_p, merge_p, str_p};
 use crate::{EngineError, Result, Session, VertexRef, cmd};
 
 // ---------------------------------------------------------------- RotoBezier
@@ -308,7 +308,7 @@ fn free_transform(s: &mut Session, p: &Value) -> Result<Value> {
         let y = v[1] * scale[1];
         [x * c - y * sn, x * sn + y * c]
     };
-    let n = s.edit("Free Transform Points", None, |proj, _| {
+    let n = s.edit("Free Transform Points", merge_p(p), |proj, _| {
         let mut n = 0;
         for (lid, uid) in &targets {
             let l = layer_mut(proj, cid, *lid)?;
@@ -360,7 +360,7 @@ fn free_transform(s: &mut Session, p: &Value) -> Result<Value> {
 
 const SHAPE_ITEMS: &[&str] = &[
     "group", "rect", "ellipse", "star", "path", "fill", "stroke", "gfill", "gstroke", "trim", "repeater", "round", "offset", "pucker", "twist", "zigzag",
-    "wiggle", "merge", "front", "bevel", "side", "back",
+    "wiggle", "wiggler", "merge", "front", "bevel", "side", "back",
 ];
 
 /// Selected shape items (contents entries) of shape layers: (layer, uid).
@@ -542,7 +542,7 @@ pub fn specs() -> Vec<CommandSpec> {
             "Free Transform Points",
             ["Layer", "Mask and Shape Path"],
             None,
-            "{layer?, mask?, scale?: % | [x%, y%], rotation?: deg, offset?: [dx, dy], anchor?: [x, y]}",
+            "{layer?, mask?, scale?: % | [x%, y%], rotation?: deg, offset?: [dx, dy], anchor?: [x, y], merge?: string}",
             has_layers,
             free_transform
         ),

crates/engine/src/cmd/prop.rs

@@ -1189,6 +1189,15 @@ fn toggle_hold(s: &mut Session, _: &Value) -> Result<Value> {
     })
 }
 
+fn set_muted(s: &mut Session, p: &Value) -> Result<Value> {
+    let muted = b_p(p, "muted").unwrap_or(true);
+    let label = if muted { "Mute Keyframes" } else { "Unmute Keyframes" };
+    edit_keys(s, label, None, move |keys, i, _| {
+        keys[i].muted = muted;
+        false
+    })
+}
+
 /// A number or a per-dimension array of numbers.
 fn nums_p(p: &Value, k: &str, scale: f64) -> Option<Vec<f64>> {
     match p.get(k)? {
@@ -1285,8 +1294,16 @@ fn convert_one_expr(s: &mut Session, cid: ItemId, lid: LayerId, uid: Uid) -> Res
     let fd = comp.frame_duration();
     let mut t = layer.in_point;
     while t < layer.out_point {
-        let ctx =
-            effectcraft_render::EvalCtx { project: &s.project, comp_id: cid, comp: &comp, time: t, expr: s.expr.as_deref(), footage: Some(s.footage.as_ref()) };
+        let ctx = effectcraft_render::EvalCtx {
+            project: &s.project,
+            comp_id: cid,
+            comp: &comp,
+            time: t,
+            expr: s.expr.as_deref(),
+            footage: Some(s.footage.as_ref()),
+            property_overrides: &[],
+            media_overrides: &[],
+        };
         keys.push(Keyframe::new(layer.layer_time(t), ctx.value(&layer, &pr)));
         t += fd;
     }
@@ -1373,6 +1390,7 @@ pub fn specs() -> Vec<CommandSpec> {
             &json!({"which": "out"})
         )),
         cmd!("keys.toggleHold", "Toggle Hold Keyframe", ["Animation"], Some("Cmd+Alt+H"), "{}", has_keys, toggle_hold),
+        cmd!("keys.setMuted", "Mute Keyframes", ["Animation"], None, "{muted?: bool (default true)}", has_keys, set_muted),
         cmd!(
             "keys.interpolation",
             "Keyframe Interpolation...",

crates/engine/src/cmd/proxy.rs

@@ -117,6 +117,7 @@ fn interpret_proxy(s: &mut Session, p: &Value) -> Result<Value> {
         return Err(bad(C, "the selected items have no proxy"));
     }
     let it = super::file_more::Interpretation::parse(p, C)?;
+    it.check(items.iter().filter_map(|i| s.project.item(*i).and_then(|x| x.proxy.as_ref()).map(|px| &px.footage)), C)?;
     let guesses: Vec<_> = items
         .iter()
         .map(|i| {
@@ -229,7 +230,7 @@ pub fn specs() -> Vec<CommandSpec> {
             "Proxy...",
             ["File", "Interpret Footage"],
             None,
-            "{items?|item?, alpha?, guessAlpha?, matteColor?|premulColor?, invertAlpha?, frameRate?, loop?, pixelAspect?, fields?, colorProfile?, linearLight?, preserveRgb?, overrideStart?, startTimecode? (as file.interpretFootage)}",
+            "{items?|item?, alpha?, guessAlpha?, matteColor?|premulColor?, invertAlpha?, frameRate?, loop?, pixelAspect?, fields?, colorProfile?, linearLight?, preserveRgb?, overrideStart?, startTimecode? (as file.interpretFootage), logConversion?, cineonUnits?, convertedBlack?, convertedWhite?, pointUnits?, tenBitBlack?, tenBitWhite?, currentGamma?, highlightRolloff? (Cineon Settings of DPX and Cineon proxies)}",
             has_proxy,
             interpret_proxy
         ),

crates/engine/src/cmd/puppet.rs

@@ -38,7 +38,8 @@ pub fn puppet_eval(s: &Session, cid: ItemId, lid: LayerId, fx_uid: Uid, t: Tick)
     let fx = layer.effects()?;
     let index = fx.groups().position(|g| g.uid == fx_uid)?;
     let g = fx.groups().nth(index)?;
-    let ctx = EvalCtx { project: &s.project, comp_id: cid, comp, time: t, expr: s.expr.as_deref(), footage: None };
+    let ctx =
+        EvalCtx { project: &s.project, comp_id: cid, comp, time: t, expr: s.expr.as_deref(), footage: None, property_overrides: &[], media_overrides: &[] };
     let mut r = Renderer::new(&s.project, &*s.footage, RenderOpts::default());
     r.expr = s.expr.as_deref();
     r.cache = Some(&s.layer_cache);

crates/engine/src/cmd/render_queue.rs

@@ -619,7 +619,7 @@ fn set_output_module(s: &mut Session, p: &Value) -> Result<Value> {
         let (w, h) = item.settings.output_size(comp);
         let mut crop_only = om.clone();
         crop_only.resize.enabled = false;
-        let (cw, ch) = crop_only.frame_size(w, h, item.settings.resolution.clamp(0.01, 4.0));
+        let (cw, ch) = crop_only.frame_size(w, h, item.settings.effective_scale(comp));
         om.resize.width = ((om.resize.height as f64 * cw as f64 / ch as f64).round() as u32).clamp(1, 30_000);
     }
     let post = match str_p(p, "postRenderAction") {

crates/engine/src/cmd/rig3d.rs

@@ -48,7 +48,16 @@ impl Env {
         Env { time: s.time_of(cid), expr: s.expr.clone(), footage: s.footage.clone() }
     }
     fn ctx<'a>(&'a self, proj: &'a Project, cid: ItemId, comp: &'a Comp) -> EvalCtx<'a> {
-        EvalCtx { project: proj, comp_id: cid, comp, time: self.time, expr: self.expr.as_deref(), footage: Some(self.footage.as_ref()) }
+        EvalCtx {
+            project: proj,
+            comp_id: cid,
+            comp,
+            time: self.time,
+            expr: self.expr.as_deref(),
+            footage: Some(self.footage.as_ref()),
+            property_overrides: &[],
+            media_overrides: &[],
+        }
     }
 }
 
@@ -268,7 +277,7 @@ fn stereo_rig(s: &mut Session, p: &Value) -> Result<Value> {
             set_expr(&mut cam, "cameraOptions/zoom", ze);
             cam.auto_orient = AutoOrient::TowardsPointOfInterest;
             let comp = proj.comp_mut(eid).ok_or(EngineError::NoComp)?;
-            comp.layers = vec![cam, nest];
+            comp.layers = vec![cam, nest].into();
             eye_comps.push(eid);
         }
         // The output comp: both eyes through 3D Glasses.
@@ -291,7 +300,7 @@ fn stereo_rig(s: &mut Session, p: &Value) -> Result<Value> {
             fxg.children.push(g.into());
         }
         let (lid, rid) = (left.id, right.id);
-        proj.comp_mut(oid).ok_or(EngineError::NoComp)?.layers = vec![left, right];
+        proj.comp_mut(oid).ok_or(EngineError::NoComp)?.layers = vec![left, right].into();
         st.project_selection = vec![oid];
         Ok(json!({
             "controls": ctl_id.0,

crates/engine/src/cmd/scripts.rs

@@ -7,6 +7,9 @@
 //!   panels appear at the bottom of the Window menu and open as dockable panels
 //!   (`window.scriptPanel`), running with `this` = the panel as in After Effects. A subfolder of
 //!   either folder (one level) is a submenu named after it; its scripts are named `Folder/File.jsx`.
+//! * **Startup and Shutdown scripts** in `Scripts/Startup/` and `Scripts/Shutdown/` run by
+//!   themselves, in alphabetical order: at launch (`file.runStartupScripts`) and as EffectCraft
+//!   quits, after the project is closed (`file.runShutdownScripts`).
 //! * **ScriptUI windows** (`scriptui.*`): list the open script windows, read their control
 //!   trees, click buttons and set values like a user, close them (see [`crate::scriptui`]).
 //! * **Script settings** (`script.settings.*`): After Effects' `app.settings`, string values by
@@ -23,6 +26,18 @@ use crate::{EngineError, Event, Result, Session, cmd, scriptui};
 /// The settings-store folders of installed scripts.
 pub const SCRIPTS_DIR: &str = "Scripts";
 pub const PANELS_DIR: &str = "Scripts/ScriptUI Panels";
+/// The settings-store folders whose scripts run at launch and as EffectCraft quits.
+pub const STARTUP_DIR: &str = "Scripts/Startup";
+pub const SHUTDOWN_DIR: &str = "Scripts/Shutdown";
+/// Commands that run script files or script code (a ScriptUI panel runs its script when it
+/// opens). Scripts and batches can't run them, and confined automation sessions refuse them.
+pub const RUNS_SCRIPTS: &[&str] =
+    &["script.run", "file.runScript", "file.runStartupScripts", "file.runShutdownScripts", "window.scriptPanel", "window.restoreScriptPanels"];
+/// Largest script file the Startup and Shutdown folders run (bytes), as `#include` and
+/// `$.evalFile` allow.
+const MAX_SCRIPT_BYTES: usize = 16 << 20;
+/// Modal dialogs a Shutdown script may open one after another; each closes as if canceled.
+const MAX_SHUTDOWN_DIALOGS: usize = 64;
 /// [`PANELS_DIR`]'s name in [`SCRIPTS_DIR`]: it holds the panels, so it is not a folder of scripts.
 const PANELS_FOLDER: &str = "ScriptUI Panels";
 /// Subfolders of Scripts that hold scripts the app runs itself (panels; launch and quit, as in
@@ -221,6 +236,7 @@ fn install(s: &mut Session, p: &Value, panel: bool) -> Result<Value> {
     let cfg = s.config.clone().ok_or_else(|| EngineError::Other("this session has no settings folder to install scripts into".into()))?;
     let dir = if panel { PANELS_DIR } else { SCRIPTS_DIR };
     cfg.write(&format!("{dir}/{name}"), &code).map_err(|e| EngineError::Other(format!("cannot install {name}: {e}")))?;
+    s.scripts_changed();
     // After Effects asks for a restart; our menus pick it up at once.
     s.toast(if panel {
         format!("Installed ScriptUI panel {name}: find it at the bottom of the Window menu")
@@ -256,6 +272,7 @@ fn uninstall(s: &mut Session, p: &Value) -> Result<Value> {
             removed = true;
         }
     }
+    s.scripts_changed();
     if removed { Ok(json!({"removed": name})) } else { Err(bad(c, format!("`{name}` is not installed"))) }
 }
 
@@ -337,6 +354,85 @@ fn restore_panels(s: &mut Session, _: &Value) -> Result<Value> {
     Ok(json!({"opened": opened, "failed": failed}))
 }
 
+/// Run the scripts in `dir` of the settings store one after another, in alphabetical order (case
+/// ignored), as After Effects runs its Startup and Shutdown folders. A script that fails is
+/// reported in a toast and the log and listed in `failed`; the next one still runs. A script waiting in a
+/// modal dialog is listed in `waiting` and goes on when the dialog closes; the next one runs
+/// meanwhile. With `quitting`, no window is left to show a dialog in, so each dialog closes as
+/// if canceled (`show()` returns 2) and the script runs on.
+fn run_folder(s: &mut Session, dir: &str, quitting: bool) -> Value {
+    let mut names: Vec<String> = s.config.as_ref().map(|c| c.list(dir)).unwrap_or_default().into_iter().filter(|n| is_script(n) && is_script_name(n)).collect();
+    names.sort_by(|a, b| a.to_lowercase().cmp(&b.to_lowercase()).then_with(|| a.cmp(b)));
+    let (mut ran, mut waiting, mut failed) = (vec![], vec![], vec![]);
+    for name in names {
+        let code = match s.config.as_ref().map(|c| c.read_bounded(&format!("{dir}/{name}"), MAX_SCRIPT_BYTES)) {
+            Some(Ok(Some(code))) => code,
+            read => {
+                let why = match read {
+                    Some(Err(e)) => format!(": {e}"),
+                    _ => String::new(),
+                };
+                let error = format!("{name}: cannot read the script{why}");
+                log::warn!("{dir}: {error}");
+                s.events.push(Event::Toast { message: error.clone(), error: true });
+                failed.push(json!({"name": name, "error": error}));
+                continue;
+            }
+        };
+        let is_waiting = |r: &Result<Value>| r.as_ref().is_ok_and(|v| v.get("waiting").and_then(Value::as_bool) == Some(true));
+        // In a settings folder on disk, the script runs as its file, so `#include`, `$.fileName`
+        // and `$.evalFile` find the files beside it.
+        let path = s.config.as_ref().and_then(|c| c.dir()).map(|d| d.join(dir).join(&name).to_string_lossy().into_owned()).unwrap_or_else(|| name.clone());
+        // Windows open before this script runs belong to other scripts, perhaps of the same name.
+        let before: Vec<u32> = s.script_ui.windows.iter().map(|w| w.id).collect();
+        let hosts_before = s.script_ui.task_hosts.clone();
+        let mut r = super::file_more::run_js_file(s, &code, &path, &name);
+        if !quitting {
+            // The Startup script's context: the one that scheduled tasks or holds the windows it
+            // opened (a task scheduled after its dialog closes runs there too).
+            let tasks = s.script_ui.task_hosts.iter().filter(|h| !hosts_before.contains(h)).copied();
+            let windows = s.script_ui.windows.iter().filter(|w| !before.contains(&w.id)).map(|w| w.host);
+            let hosts: Vec<u32> = tasks.chain(windows).collect();
+            for h in hosts {
+                if !s.script_ui.startup_hosts.contains(&h) {
+                    s.script_ui.startup_hosts.push(h);
+                }
+            }
+        }
+        let mut closed = 0;
+        while quitting && closed < MAX_SHUTDOWN_DIALOGS && is_waiting(&r) {
+            let Some(id) = s.script_ui.windows.iter().rev().find(|w| w.modal && w.script == path && !before.contains(&w.id)).map(|w| w.id) else { break };
+            // report_js reports an error the script throws after its dialog closes, as it does for an
+            // error in the script's first run.
+            r = scriptui::close(s, &json!({"window": id})).and_then(|out| super::file_more::report_js(s, &name, out));
+            closed += 1;
+        }
+        match r {
+            Ok(_) if is_waiting(&r) => waiting.push(name),
+            Ok(_) => ran.push(name),
+            Err(e) => {
+                // Also in the log: no frame draws a Shutdown script's toast.
+                log::warn!("{dir}: {e}");
+                failed.push(json!({"name": name, "error": e.to_string()}));
+            }
+        }
+    }
+    json!({"ran": ran, "waiting": waiting, "failed": failed})
+}
+
+/// `file.runStartupScripts`: run the scripts in `Scripts/Startup` (frontends call it once at
+/// launch, before a project opens).
+fn run_startup(s: &mut Session, _: &Value) -> Result<Value> {
+    Ok(run_folder(s, STARTUP_DIR, false))
+}
+
+/// `file.runShutdownScripts`: close the project, then run the scripts in `Scripts/Shutdown`
+/// (frontends call it as the app quits, after the unsaved-changes prompt).
+fn run_shutdown(s: &mut Session, _: &Value) -> Result<Value> {
+    s.replace_project(effectcraft_project::Project::default(), None);
+    Ok(run_folder(s, SHUTDOWN_DIR, true))
+}
+
 /// Window ▸ `<ScriptUI panel>`: run the panel script (or bring its panel forward).
 fn open_panel(s: &mut Session, p: &Value) -> Result<Value> {
     let c = "window.scriptPanel";
@@ -414,6 +510,24 @@ pub fn specs() -> Vec<CommandSpec> {
             always,
             restore_panels
         ),
+        cmd!(
+            "file.runStartupScripts",
+            "Run Startup Scripts",
+            [],
+            None,
+            "{} → runs the scripts in Scripts/Startup in alphabetical order (frontends call it at launch) → {ran: [name], waiting: [name] (in a modal dialog), failed: [{name, error}]}",
+            always,
+            run_startup
+        ),
+        cmd!(
+            "file.runShutdownScripts",
+            "Run Shutdown Scripts",
+            [],
+            None,
+            "{} → closes the project, then runs the scripts in Scripts/Shutdown in alphabetical order (frontends call it as the app quits; their modal dialogs close as if canceled) → {ran: [name], waiting: [name], failed: [{name, error}]}",
+            always,
+            run_shutdown
+        ),
         crate::query!("script.settings.get", "Get Script Setting", "{section, key} → {have, value} (app.settings.haveSetting / getSetting)", settings_get),
         cmd!(
             "script.settings.save",
@@ -463,7 +577,7 @@ pub fn specs() -> Vec<CommandSpec> {
             "Mouse Event on Script Window Control",
             [],
             None,
-            "{window?, widget, type: mousedown | mouseup | mousemove | mouseover | mouseout | click (default), x?, y? (relative to the control; default its centre), button? (0 left, 1 middle, 2 right), detail? (click count), screenX?, screenY?, altKey?, ctrlKey?, metaKey?, shiftKey?} → the script's addEventListener listeners on the control and its containers receive a MouseEvent",
+            "{window?, widget, type: mousedown | mouseup | mousemove | mouseover | mouseout | click (default), x?, y? (relative to the control; default its centre), button? (0 left, 1 middle, 2 right), buttons? (held: 1 left, 2 right, 4 middle), detail? (click count), screenX?, screenY?, altKey?, ctrlKey?, metaKey?, shiftKey?} → the script's addEventListener listeners on the control and its containers receive a MouseEvent",
             always,
             scriptui::mouse
         ),
@@ -948,4 +1062,64 @@ mod tests {
         assert!(bad_params(&s.execute("file.uninstallScript", json!({"name": "Hello.jsx"}))), "no longer installed");
         let _ = std::fs::remove_dir_all(&root);
     }
+
+    /// Edit ▸ Keyboard Shortcuts lists the scripts File ▸ Scripts lists (not ScriptUI panels),
+    /// as soon as one is installed and until it is uninstalled; a key given to one is saved with
+    /// the preset.
+    #[test]
+    fn file_scripts_entries_take_keyboard_shortcuts() {
+        use crate::shortcuts::{Keymaps, SHORTCUTS_FILE, binding_key};
+        let (mut s, root) = session_in_tmp("shortcuts");
+        let (script, panel) = (root.join("Hello.jsx"), root.join("Hello Panel.jsx"));
+        std::fs::write(&script, "hello").unwrap();
+        std::fs::write(&panel, "panel").unwrap();
+        let listed = |s: &Session, name: &str| {
+            s.shortcuts().find(&binding_key("file.runScript", &json!({"name": name}))).map(|b| (b.label.clone(), b.path.join(" ▸ "), b.defaults.clone()))
+        };
+        assert_eq!(listed(&s, "Rename Layers.jsx"), Some(("Rename Layers.jsx".into(), "File ▸ Scripts".into(), vec![])), "the bundled samples");
+        assert_eq!(listed(&s, "Hello.jsx"), None);
+        s.execute("file.installScript", json!({"path": script.to_string_lossy()})).unwrap();
+        s.execute("file.installScriptUIPanel", json!({"path": panel.to_string_lossy()})).unwrap();
+        assert_eq!(listed(&s, "Hello.jsx"), Some(("Hello.jsx".into(), "File ▸ Scripts".into(), vec![])));
+        assert_eq!(listed(&s, "Hello Panel.jsx"), None, "panels are in the Window menu");
+        let r = s.execute("shortcuts.set", json!({"command": "file.runScript", "params": {"name": "Hello.jsx"}, "keys": "Cmd+Alt+Shift+F7"})).unwrap();
+        let key = binding_key("file.runScript", &json!({"name": "Hello.jsx"}));
+        assert_eq!((&r["command"], &r["keys"]), (&json!(key), &json!(["Cmd+Alt+Shift+F7"])), "{r}");
+        assert_eq!(s.shortcuts().shortcut_of("file.runScript", &json!({"name": "Hello.jsx"})), Some("Cmd+Alt+Shift+F7"));
+        let saved = Keymaps::from_json(&std::fs::read_to_string(root.join("settings").join(SHORTCUTS_FILE)).unwrap());
+        assert_eq!(saved.active_preset().and_then(|p| p.overrides.get(&key)), Some(&vec!["Cmd+Alt+Shift+F7".to_string()]));
+        s.execute("file.uninstallScript", json!({"name": "Hello.jsx"})).unwrap();
+        assert_eq!(listed(&s, "Hello.jsx"), None);
+        let _ = std::fs::remove_dir_all(&root);
+    }
+
+    /// `shortcuts.list` and `shortcuts.set` see a script copied into the Scripts folder by hand
+    /// after the shortcut table was built; a script the folder doesn't hold (never there, or
+    /// removed by hand) can't take a key, and Run Script File… keeps its own keys.
+    #[test]
+    fn shortcut_commands_find_scripts_copied_into_the_folder() {
+        let (mut s, root) = session_in_tmp("copied");
+        assert!(s.shortcuts().find("file.runScript").is_some(), "the table is built");
+        std::fs::create_dir_all(root.join("settings").join(SCRIPTS_DIR)).unwrap();
+        std::fs::write(root.join("settings").join(SCRIPTS_DIR).join("Copied.jsx"), "copied").unwrap();
+        let list = s.execute("shortcuts.list", json!({"query": "copied.jsx"})).unwrap();
+        assert_eq!(list["count"], 1, "{list}");
+        let r = s.execute("shortcuts.set", json!({"command": "file.runScript", "params": {"name": "Copied.jsx"}, "keys": "Cmd+Alt+Shift+F7"})).unwrap();
+        assert_eq!(r["command"], r#"file.runScript {"name":"Copied.jsx"}"#, "{r}");
+        let r = s.execute("shortcuts.set", json!({"command": "file.runScript", "params": {"name": "Missing.jsx"}, "keys": "Cmd+Alt+Shift+F8"}));
+        assert!(bad_params(&r), "{r:?}");
+        // The binding-key form finds a script copied in since the last lookup, too.
+        std::fs::write(root.join("settings").join(SCRIPTS_DIR).join("Second.jsx"), "second").unwrap();
+        let r = s.execute("shortcuts.set", json!({"command": r#"file.runScript {"name":"Second.jsx"}"#, "keys": "Cmd+Alt+Shift+F10"})).unwrap();
+        assert_eq!(r["command"], r#"file.runScript {"name":"Second.jsx"}"#, "{r}");
+        // Removed by hand: no longer in the folder.
+        std::fs::remove_file(root.join("settings").join(SCRIPTS_DIR).join("Copied.jsx")).unwrap();
+        std::fs::remove_file(root.join("settings").join(SCRIPTS_DIR).join("Second.jsx")).unwrap();
+        let r = s.execute("shortcuts.set", json!({"command": r#"file.runScript {"name":"Second.jsx"}"#, "keys": "Cmd+Alt+Shift+F11"}));
+        assert!(bad_params(&r), "{r:?}");
+        let r = s.execute("shortcuts.set", json!({"command": "file.runScript", "params": {"name": "Copied.jsx"}, "keys": "Cmd+Alt+Shift+F9"}));
+        assert!(bad_params(&r), "{r:?}");
+        assert_eq!(s.shortcuts().shortcut_of("file.runScript", &Value::Null), None, "Run Script File… has no key");
+        let _ = std::fs::remove_dir_all(&root);
+    }
 }

crates/engine/src/cmd/settings.rs

@@ -73,13 +73,21 @@ fn prefs_pages(_: &mut Session, _: &Value) -> Result<Value> {
 
 // ---------------------------------------------------------------- shortcuts
 
-/// The bindable named by `command` (+ `params`), or by a binding key (`app.settings {...}`).
-fn bindable(s: &Session, p: &Value, cmd: &str) -> Result<crate::shortcuts::Bindable> {
+/// The bindable named by `command` (+ `params`), or by a binding key (`app.settings {...}`). A
+/// File ▸ Scripts entry (`file.runScript {"name": …}`) is looked up in File ▸ Scripts' list as it
+/// is now (the Scripts folder and the bundled scripts), and a script it doesn't list is an error,
+/// not Run Script File….
+fn bindable(s: &mut Session, p: &Value, cmd: &str) -> Result<crate::shortcuts::Bindable> {
     let c = str_p(p, "command").ok_or_else(|| bad(cmd, "missing `command`"))?;
     let params = p.get("params").cloned().unwrap_or(Value::Null);
-    let t = s.shortcuts();
     let key = binding_key(c, &params);
-    t.find(&key).or_else(|| t.find(c)).cloned().ok_or_else(|| bad(cmd, format!("`{key}` can't have a shortcut (see shortcuts.list)")))
+    let script = (c == "file.runScript" && params.get("name").is_some()) || c.starts_with("file.runScript {");
+    if script {
+        s.scripts_changed();
+    }
+    let t = s.shortcuts();
+    let found = if script { t.find(&key) } else { t.find(&key).or_else(|| t.find(c)) };
+    found.cloned().ok_or_else(|| bad(cmd, format!("`{key}` can't have a shortcut (see shortcuts.list)")))
 }
 
 fn keys_param(p: &Value, cmd: &str) -> Result<Vec<String>> {
@@ -93,6 +101,8 @@ fn keys_param(p: &Value, cmd: &str) -> Result<Vec<String>> {
 }
 
 fn sc_list(s: &mut Session, p: &Value) -> Result<Value> {
+    // Scripts copied into the Scripts folder since the table was built are listed too.
+    s.scripts_changed();
     let q = str_p(p, "query").unwrap_or("").to_lowercase();
     let assigned = p.get("assigned").and_then(Value::as_bool).unwrap_or(false);
     let keys_q = str_p(p, "keys").and_then(normalize);

crates/engine/src/cmd/shape_tool.rs

@@ -180,16 +180,17 @@ fn rgba(c: [f32; 3]) -> [f64; 4] {
     [c[0] as f64, c[1] as f64, c[2] as f64, 1.0]
 }
 
-/// The Rounded Rectangle tool's corner roundness for `size`.
-fn roundness(size: [f64; 2]) -> f64 {
-    size[0].min(size[1]) * 0.15
+/// The Rounded Rectangle tool's corner roundness: a fixed default, as in After Effects
+/// (it does not grow with the drawn size).
+fn roundness() -> f64 {
+    20.0
 }
 
 /// The Polygon and Star tools' Polystar for `size`: (star, points, outer radius, inner radius).
 fn polystar_of(kind: &str, size: [f64; 2]) -> Option<(bool, f64, f64, f64)> {
     match kind {
         "star" => Some((true, 5.0, size[0] / 2.0, size[0] / 4.0)),
-        "polygon" => Some((false, 6.0, size[0] / 2.0, 0.0)),
+        "polygon" => Some((false, 5.0, size[0] / 2.0, 0.0)),
         _ => None,
     }
 }
@@ -199,7 +200,7 @@ fn polystar_of(kind: &str, size: [f64; 2]) -> Option<(bool, f64, f64, f64)> {
 pub(crate) fn shape_group(ids: &mut Ids, kind: &str, size: [f64; 2], paint: &ShapeTool) -> Option<PropGroup> {
     let (path, gname) = match kind {
         "rect" | "rectangle" => (build::shape_rect(ids, size, [0.0, 0.0], 0.0), "Rectangle 1"),
-        "rounded" | "roundedRect" => (build::shape_rect(ids, size, [0.0, 0.0], roundness(size)), "Rectangle 1"),
+        "rounded" | "roundedRect" => (build::shape_rect(ids, size, [0.0, 0.0], roundness()), "Rectangle 1"),
         "ellipse" => (build::shape_ellipse(ids, size, [0.0, 0.0]), "Ellipse 1"),
         k => {
             let (star, points, outer, inner) = polystar_of(k, size)?;
@@ -218,7 +219,7 @@ pub fn mask_path(kind: &str, centre: [f64; 2], size: [f64; 2]) -> Option<ShapePa
     let bez = match kind {
         "rect" | "rectangle" => return Some(ShapePath::rect(centre, size[0], size[1])),
         "ellipse" => return Some(ShapePath::ellipse(centre, size[0], size[1])),
-        "rounded" | "roundedRect" => effectcraft_path::rect(size, centre, roundness(size)),
+        "rounded" | "roundedRect" => effectcraft_path::rect(size, centre, roundness()),
         k => {
             let (star, points, outer, inner) = polystar_of(k, size)?;
             effectcraft_path::polystar(effectcraft_path::Polystar {

crates/engine/src/cmd/text_anim.rs

@@ -142,6 +142,7 @@ fn add_animator_prop(s: &mut Session, p: &Value) -> Result<Value> {
     }
     let layer = s.project.comp(cid).and_then(|c| c.layer(lid)).cloned().ok_or_else(|| bad(C, "no layer"))?;
     let auid = animator_uid(s, &layer, p, C)?;
+    let mut index = 0;
     s.edit("Add Text Animator Property", None, |proj, _| {
         let mut next = proj.next_id;
         let mut ids = Ids(&mut next);
@@ -151,10 +152,13 @@ fn add_animator_prop(s: &mut Session, p: &Value) -> Result<Value> {
         for k in &kinds {
             add_props(&mut ids, anim, k, three);
         }
+        // The requested property's 1-based position in the Properties group. A companion (such as
+        // Tracking Type) is added before it, so the first new child is not always the one asked for.
+        index = kinds.first().and_then(|k| anim.sub("properties")?.children.iter().position(|n| n.match_id() == k.as_str())).map_or(0, |i| i + 1);
         proj.next_id = next;
         Ok(())
     })?;
-    Ok(json!({"animator": auid}))
+    Ok(json!({"animator": auid, "index": index}))
 }
 
 pub(crate) fn add_selector(s: &mut Session, p: &Value) -> Result<Value> {

crates/engine/src/cmd/text_edit.rs

@@ -71,7 +71,8 @@ pub struct TextEdit {
     /// Character panel changes made with only a caret: the style the next typed text takes.
     #[serde(default)]
     pub pending: Option<CharStyle>,
-    /// The layer was made by a Type tool click; leaving it empty deletes it.
+    /// The layer was made by a Type tool click. Kept when left empty, as After Effects does, so this
+    /// only records how the edit began.
     #[serde(default)]
     pub created: bool,
     /// Line position kept by repeated up / down moves (layout space).
@@ -372,18 +373,14 @@ fn edit(s: &mut Session, p: &Value) -> Result<Value> {
     Ok(state_json(s))
 }
 
-/// `text.endEdit`: stop editing (a Type-tool layer left empty is deleted).
+/// `text.endEdit`: stop editing.
+///
+/// A Type-tool layer the user clicked away from without typing is **kept**: After Effects leaves it in
+/// the timeline as `<空白のテキストレイヤー>`, and the layer came from the user's click rather than from a
+/// mistake to clean up. Deleting it took away something they could still type into.
 pub(crate) fn end_edit(s: &mut Session, _: &Value) -> Result<Value> {
-    let Some(e) = s.state.text_edit.take() else { return Ok(Value::Null) };
-    if e.created && layer_doc(s, e.layer).is_some_and(|d| d.text.is_empty()) {
-        let cid = s.active_comp_id().ok_or(EngineError::NoComp)?;
-        s.edit("Delete Empty Text Layer", None, |proj, st| {
-            if let Some(c) = proj.comp_mut(cid) {
-                c.layers.retain(|l| l.id != e.layer);
-            }
-            st.selected_layers.retain(|l| *l != e.layer);
-            Ok(())
-        })?;
+    if s.state.text_edit.take().is_none() {
+        return Ok(Value::Null);
     }
     s.bump();
     Ok(Value::Null)

crates/engine/src/cmd/three_d.rs

@@ -12,6 +12,7 @@ use effectcraft_time::Tick;
 use serde_json::{Value, json};
 
 use super::layer::{color_p, insert_layer};
+use super::model3d::{report_switch, use_advanced_3d};
 use super::{CommandSpec, b_p, bad, comp_id, f_p, has_comp, layer_mut, layer_p, merge_p, str_p, time_p};
 use crate::{EngineError, Result, Session, cmd, query};
 
@@ -227,12 +228,17 @@ fn new_light(s: &mut Session, p: &Value) -> Result<Value> {
     };
     let name = str_p(p, "name").unwrap_or("Light 1").to_string();
     let t = time_p(s, p, Some(&comp));
-    let id = s.edit("New Light", None, |proj, st| {
+    // Only the Advanced 3D renderer lights with Environment lights, so adding one switches a
+    // Classic 3D comp to it, like After Effects (inside the adding edit: one undo step).
+    let env = kind == LightKind::Environment;
+    let (id, switched) = s.edit("New Light", None, |proj, st| {
         let mut l = build::layer(proj, &comp, &name, LayerSource::Light { kind }, (comp.width, comp.height), None);
         apply_light(&mut l, p, t, "layer.newLight")?;
-        insert_layer(proj, st, cid, l)
+        let id = insert_layer(proj, st, cid, l)?;
+        Ok((id, if env { use_advanced_3d(proj, cid)? } else { false }))
     })?;
-    Ok(json!({"layer": id.0}))
+    report_switch(s, cid, switched, "which Environment lights need to light the scene");
+    Ok(json!({"layer": id.0, "advanced3d": env}))
 }
 
 fn light_settings(s: &mut Session, p: &Value) -> Result<Value> {
@@ -248,7 +254,7 @@ fn light_settings(s: &mut Session, p: &Value) -> Result<Value> {
         ),
         None => None,
     };
-    s.edit("Light Settings", None, |proj, _| {
+    let switched = s.edit("Light Settings", None, |proj, _| {
         let old = proj.comp(cid).and_then(|c| c.layer(lid)).cloned().ok_or(EngineError::NoComp)?;
         let mut l = old.clone();
         if let Some(k) = kind
@@ -288,9 +294,14 @@ fn light_settings(s: &mut Session, p: &Value) -> Result<Value> {
             l.name = n.clone();
         }
         apply_light(&mut l, p, t, "layer.lightSettings")?;
+        // A light that becomes an Environment light switches a Classic 3D comp to Advanced 3D,
+        // like adding one does; editing one that already is leaves the renderer to the user.
+        let was_env = matches!(old.source, LayerSource::Light { kind: LightKind::Environment });
+        let is_env = matches!(l.source, LayerSource::Light { kind: LightKind::Environment });
         *layer_mut(proj, cid, lid)? = l;
-        Ok(())
+        Ok(if !was_env && is_env { use_advanced_3d(proj, cid)? } else { false })
     })?;
+    report_switch(s, cid, switched, "which Environment lights need to light the scene");
     Ok(Value::Null)
 }
 
@@ -413,7 +424,8 @@ fn get_3d(s: &mut Session, p: &Value) -> Result<Value> {
     let (w, h) = (comp.width as f64, comp.height as f64);
     let vs = s.state.views3d.get(&cid).cloned().unwrap_or_default();
     let t = s.state.times.get(&cid).copied().unwrap_or(Tick::ZERO);
-    let ctx = EvalCtx { project: &s.project, comp_id: cid, comp, time: t, expr: s.expr.as_deref(), footage: None };
+    let ctx =
+        EvalCtx { project: &s.project, comp_id: cid, comp, time: t, expr: s.expr.as_deref(), footage: None, property_overrides: &[], media_overrides: &[] };
     let cam = vs.override_camera(w, h).unwrap_or_else(|| camera::active_camera(&ctx));
     let f = cam.forward();
     let lights: Vec<Value> = comp
@@ -532,7 +544,7 @@ fn auto_orient(s: &mut Session, p: &Value) -> Result<Value> {
     };
     s.edit("Auto-Orient", None, |proj, _| {
         let comp = proj.comp_mut(cid).ok_or(EngineError::NoComp)?;
-        for l in comp.layers.iter_mut().filter(|l| ids.contains(&l.id)) {
+        for l in comp.layers.iter_mut_where(|l| ids.contains(&l.id)) {
             let rig = l.is_camera() || l.is_light();
             let ok = match mode {
                 AutoOrient::Off | AutoOrient::AlongPath => true,
@@ -555,7 +567,8 @@ fn auto_orient(s: &mut Session, p: &Value) -> Result<Value> {
 /// through each layer's world matrix; cameras and lights contribute their position).
 fn layer_points(s: &Session, cid: ItemId, ids: &[LayerId], t: Tick) -> Vec<Vec3> {
     let Some(comp) = s.project.comp(cid) else { return vec![] };
-    let ctx = EvalCtx { project: &s.project, comp_id: cid, comp, time: t, expr: s.expr.as_deref(), footage: None };
+    let ctx =
+        EvalCtx { project: &s.project, comp_id: cid, comp, time: t, expr: s.expr.as_deref(), footage: None, property_overrides: &[], media_overrides: &[] };
     let mut out = vec![];
     for l in comp.layers.iter().filter(|l| ids.contains(&l.id)) {
         let m = ctx.world_matrix(l);
@@ -681,7 +694,7 @@ pub fn specs() -> Vec<CommandSpec> {
             "Light...",
             ["Layer", "New"],
             Some("Cmd+Alt+Shift+L"),
-            "{kind?: Parallel|Spot|Point|Ambient|Environment (default Spot; Environment lights and reflects from an equirectangular image layer: prop.set its lightOptions/source to that layer's id, or leave it empty for the comp's Environment Layer, see layer.environment), name?, color?, intensity?, coneAngle?, coneFeather?, falloff?: None|Smooth|Inverse Square Clamped, radius?, falloffDistance?, castsShadows?, shadowDarkness?, shadowDiffusion?, position? [x,y,z], poi? [x,y,z]}",
+            "{kind?: Parallel|Spot|Point|Ambient|Environment (default Spot; Environment lights and reflects from an equirectangular image layer: prop.set its lightOptions/source to that layer's id, or leave it empty for the comp's Environment Layer or a flat default environment of its colour and intensity, see layer.environment; an Environment light switches a Classic 3D comp to Advanced 3D), name?, color?, intensity?, coneAngle?, coneFeather?, falloff?: None|Smooth|Inverse Square Clamped, radius?, falloffDistance?, castsShadows?, shadowDarkness?, shadowDiffusion?, position? [x,y,z], poi? [x,y,z]}",
             has_comp,
             new_light
         ),
@@ -708,7 +721,7 @@ pub fn specs() -> Vec<CommandSpec> {
             "Light Settings...",
             [],
             None,
-            "{layer?, name?, kind?: Parallel|Spot|Point|Ambient|Environment, color?, intensity?, coneAngle?, coneFeather?, falloff?, radius?, falloffDistance?, castsShadows?, shadowDarkness?, shadowDiffusion?, position?, poi?}",
+            "{layer?, name?, kind?: Parallel|Spot|Point|Ambient|Environment (changing to Environment switches a Classic 3D comp to Advanced 3D), color?, intensity?, coneAngle?, coneFeather?, falloff?, radius?, falloffDistance?, castsShadows?, shadowDarkness?, shadowDiffusion?, position?, poi?}",
             has_comp,
             light_settings
         ),

crates/engine/src/footage/footage_reload.rs

@@ -81,6 +81,8 @@ fn refreshed(s: &Session, f: &Footage, probed: Footage) -> Footage {
     nf.codec = probed.codec;
     nf.has_video = probed.has_video;
     nf.has_audio = probed.has_audio;
+    // The markers the file carries now (a WAV's cue points), for Update Markers From Source.
+    nf.markers = probed.markers;
     if matches!(f.kind, FootageKind::Video | FootageKind::Audio) {
         nf.duration = probed.duration;
         // Interpret Footage ▸ Conform to frame rate stays; the file's own rate is refreshed.

crates/engine/src/footage/sequence.rs

@@ -45,14 +45,13 @@ impl SequenceOptions {
     /// `file.import`'s options. Dropped files (`drag: true`) import as stills, as in After
     /// Effects, while a folder's numbered stills import as sequences unless `sequence: false`
     /// (Alt-drag of a folder). The Import dialog passes its `"<format> Sequence"` checkbox (off
-    /// unless ticked) as `sequence`. Without `sequence` or `drag` (scripts, agents) a numbered
-    /// still brings its run, as it always has.
+    /// unless ticked) as `sequence`. Without `sequence` (scripts, agents) a numbered still imports
+    /// as itself, as `ImportOptions.sequence` defaults to false in After Effects (#2018).
     pub fn for_import(p: &serde_json::Value) -> SequenceOptions {
         let flag = |k: &str| p.get(k).and_then(serde_json::Value::as_bool);
         let (sequence, alphabetical) = (flag("sequence"), flag("alphabetical").unwrap_or(false));
-        let dropped = flag("drag").unwrap_or(false);
         // Force Alphabetical Order is part of the Sequence option.
-        SequenceOptions { sequence: sequence.unwrap_or(alphabetical || !dropped), folders: sequence.unwrap_or(true), alphabetical }
+        SequenceOptions { sequence: sequence.unwrap_or(alphabetical), folders: sequence.unwrap_or(true), alphabetical }
     }
 }
 

crates/engine/src/home/demo.rs

@@ -121,7 +121,7 @@ fn lower_third(p: &mut Project) -> Comp {
         [440.0, 914.0],
     );
     anim(&mut title, "transform/opacity", keys(&[(0.4, Value::Scalar(0.0)), (0.9, Value::Scalar(100.0))]));
-    c.layers = vec![title, bar];
+    c.layers = vec![title, bar].into();
     c
 }
 
@@ -270,7 +270,7 @@ fn showcase_3d(p: &mut Project, solids: ItemId) -> Comp {
     );
     anim(&mut caption, "transform/opacity", keys(&[(0.3, Value::Scalar(0.0)), (1.2, Value::Scalar(100.0))]));
 
-    c.layers = vec![caption, cam, key, fill, title, left, right, x1, x2, floor];
+    c.layers = vec![caption, cam, key, fill, title, left, right, x1, x2, floor].into();
     c
 }
 
@@ -463,7 +463,7 @@ pub fn demo_project() -> Project {
     lower.out_point = t(9.5);
 
     // Stack: top first.
-    comp.layers = vec![lower, title, sub, line, burst, rings, null, bg];
+    comp.layers = vec![lower, title, sub, line, burst, rings, null, bg].into();
     for l in &mut comp.layers {
         if l.name == "Controller" {
             l.switches.video = false;

crates/engine/src/menus.rs

@@ -1036,6 +1036,8 @@ Animation
   ---
   Add Keyframe | anim.addKeyframe
   Toggle Hold Keyframe | keys.toggleHold
+  Mute Keyframes | keys.setMuted
+  Unmute Keyframes | keys.setMuted {"muted":false}
   Keyframe Interpolation... | keys.interpolation
   Keyframe Velocity... | keys.velocity
   Keyframe Assistant

crates/engine/src/render_queue.rs

@@ -686,7 +686,7 @@ impl Session {
                         continue;
                     }
                     if let Some(c) = proj.comp_mut(cid) {
-                        for l in c.layers.iter_mut().filter(|l| matches!(l.source, LayerSource::Comp { item } if item == comp)) {
+                        for l in c.layers.iter_mut_where(|l| matches!(l.source, LayerSource::Comp { item } if item == comp)) {
                             l.source = LayerSource::Footage { item: fid };
                         }
                     }

crates/engine/src/scriptui.rs

@@ -402,12 +402,16 @@ pub struct ScriptUi {
     #[serde(skip)]
     pub tasks: Option<ScriptTaskRunner>,
     /// Bumped whenever the project is closed or replaced (New / Open / Close Project): repeating
-    /// tasks of scripts without an open window stop then.
+    /// tasks of scripts without an open window stop then, except those of Startup scripts.
     #[serde(skip)]
     pub project_epoch: u64,
     /// The script contexts of this session with scheduled tasks (kept by the scripting engine).
     #[serde(skip)]
     pub task_hosts: Vec<u32>,
+    /// The script contexts of Startup scripts: their tasks go on when the project is closed or
+    /// replaced, until EffectCraft quits.
+    #[serde(skip)]
+    pub startup_hosts: Vec<u32>,
 }
 
 impl ScriptUi {
@@ -755,6 +759,7 @@ pub(crate) fn mouse(s: &mut Session, p: &Value) -> Result<Value> {
         "screenX": num("screenX", -FAR, FAR, 0.0),
         "screenY": num("screenY", -FAR, FAR, 0.0),
         "button": num("button", 0.0, 2.0, 0.0).round(),
+        "buttons": num("buttons", 0.0, 7.0, 0.0).round(),
         "detail": num("detail", 0.0, 1000.0, clicks).round(),
         "altKey": flag("altKey"),
         "ctrlKey": flag("ctrlKey"),

crates/engine/src/services.rs

@@ -50,8 +50,20 @@ pub trait Services: Send + Sync {
 pub struct FsServices;
 
 impl Services for FsServices {
+    /// Refuses what isn't a regular file: a project can name `/dev/zero` or a FIFO, and reading
+    /// those never ends (#2134).
     fn read_file(&self, path: &str) -> std::io::Result<Vec<u8>> {
-        std::fs::read(path)
+        use std::io::Read;
+        let mut file = std::fs::File::open(path)?;
+        let meta = file.metadata()?;
+        if !meta.is_file() {
+            return Err(std::io::Error::new(std::io::ErrorKind::InvalidInput, format!("{path} is not a file")));
+        }
+        let mut bytes = Vec::new();
+        // A sparse file can claim far more than memory: an error, not an abort.
+        bytes.try_reserve_exact(usize::try_from(meta.len()).unwrap_or(usize::MAX)).map_err(|e| std::io::Error::new(std::io::ErrorKind::OutOfMemory, e))?;
+        file.read_to_end(&mut bytes)?;
+        Ok(bytes)
     }
     fn write_file(&self, path: &str, data: &[u8]) -> std::io::Result<()> {
         config::atomic_write(std::path::Path::new(path), data)
@@ -70,3 +82,21 @@ pub trait Importer: Send + Sync {
     /// media layer reads from memory (the browser) register them; file-based ones need nothing.
     fn add_frames(&self, _paths: &[String]) {}
 }
+
+#[cfg(test)]
+mod tests {
+    use super::{FsServices, Services};
+
+    /// #2134: a project can name a folder, `/dev/zero` or a FIFO; reading those is an error.
+    #[test]
+    fn fs_services_read_only_regular_files() {
+        let dir = std::env::temp_dir();
+        assert!(FsServices.read_file(&dir.to_string_lossy()).is_err());
+        #[cfg(unix)]
+        assert!(FsServices.read_file("/dev/zero").is_err());
+        let f = dir.join(format!("ec-services-read-{}.txt", std::process::id()));
+        std::fs::write(&f, b"data").unwrap();
+        assert_eq!(FsServices.read_file(&f.to_string_lossy()).unwrap(), b"data");
+        let _ = std::fs::remove_file(f);
+    }
+}

crates/engine/src/session/render.rs

@@ -96,7 +96,7 @@ impl Session {
             effectcraft_project::ItemKind::Footage(f) if f.has_video => {
                 let f = f.clone();
                 Some(Box::new(move || {
-                    let img = footage.frame(item, &f, Tick(0))?;
+                    let img = effectcraft_render::cineon_frame(footage.frame(item, &f, Tick(0))?, &f);
                     // Point-sample down to at most `max_side` on the long side.
                     let step = (img.width.max(img.height) as f32 / max_side.max(1) as f32).ceil().max(1.0) as u32;
                     let (w, h) = (img.width.div_ceil(step), img.height.div_ceil(step));

crates/engine/src/settings/prefs/choices.rs

@@ -8,6 +8,7 @@ pub const LANGUAGES: &[(&str, &str)] = &[
     ("Deutsch", "de"),
     ("Español", "es"),
     ("Français", "fr"),
+    ("Polski", "pl"),
     ("Português (Brasil)", "pt-br"),
     ("Русский", "ru"),
     ("Українська", "uk"),

crates/engine/src/settings/prefs/dialog.rs

@@ -122,6 +122,11 @@ pub fn pages() -> Vec<Page> {
                 Section("New Project"),
                 s("project.useTemplate", "New Project Loads Template", B, true),
                 s("project.templatePath", "Template Project", Kind::Path, true),
+                Section("Project Files"),
+                s("project.compactProjectFiles", "Save Compact Project Files", B, true),
+                Note(
+                    "Saves .ecproj files as compact JSON on one line: smaller and faster to save and open, but hard to read or diff in version control. Off, they are indented, one value per line.",
+                ),
                 Section("Auto-Save"),
                 s("autoSave.enabled", "Automatically Save Projects", B, true),
                 s("autoSave.intervalMinutes", "Save Every", Kind::Int(1, 240, "Minutes"), true),

crates/engine/src/settings/prefs/sections.rs

@@ -62,6 +62,9 @@ page!(ProjectPrefs {
     /// Open a template project for File ▸ New ▸ New Project.
     use_template: bool = false,
     template_path: String = String::new(),
+    /// Write `.ecproj` files as compact JSON on one line (smaller, faster to save and open). Off:
+    /// indented, one value per line, so they read and diff cleanly in version control.
+    compact_project_files: bool = false,
 });
 
 page!(AutoSave {

crates/engine/src/settings/session_settings.rs

@@ -195,9 +195,19 @@ impl Session {
         self.shortcut_table = std::sync::OnceLock::new();
     }
 
-    /// The active shortcut preset resolved against every bindable command.
+    /// The scripts in the Scripts folder changed: list File ▸ Scripts' entries again in the
+    /// shortcut table.
+    pub fn scripts_changed(&mut self) {
+        self.shortcut_table = std::sync::OnceLock::new();
+    }
+
+    /// The active shortcut preset resolved against every bindable command, File ▸ Scripts'
+    /// entries included.
     pub fn shortcuts(&self) -> &ShortcutTable {
-        self.shortcut_table.get_or_init(|| ShortcutTable::build(&self.keymaps, &self.ui_commands))
+        self.shortcut_table.get_or_init(|| {
+            let scripts: Vec<String> = crate::commands::scripts::scripts(self).into_iter().filter(|e| !e.panel).map(|e| e.name).collect();
+            ShortcutTable::build_with_scripts(&self.keymaps, &self.ui_commands, &scripts)
+        })
     }
 
     /// Remember a project in File ▸ Open Recent and in the crash-recovery sentinel.

crates/engine/src/settings/shortcuts.rs

@@ -1,6 +1,7 @@
 //! Keyboard shortcut presets (Edit ▸ Keyboard Shortcuts).
 //!
-//! Every menu entry, registry command and frontend command is *bindable*: it has a binding key
+//! Every menu entry, registry command and frontend command, and every script File ▸ Scripts
+//! lists, is *bindable*: it has a binding key
 //! (the command id, plus its bound parameters for entries such as `app.settings
 //! {"page":"general"}`), a scope (application-wide or a panel) and default keys. The built-in
 //! preset "EffectCraft Default" is After Effects' default keyboard layout and is read-only; custom
@@ -157,6 +158,27 @@ pub fn bindables(ui: &[UiCommand]) -> Vec<Bindable> {
     out
 }
 
+/// The File ▸ Scripts entries of the scripts `names` (file names, as the menu lists them), with
+/// no default keys. A key is bound to the script's name, so it stays with that script when
+/// scripts are added to or removed from the folder.
+pub fn script_bindables(names: &[String]) -> Vec<Bindable> {
+    names
+        .iter()
+        .map(|n| {
+            let params = json!({"name": n});
+            Bindable {
+                key: binding_key("file.runScript", &params),
+                command: "file.runScript".into(),
+                params,
+                label: n.clone(),
+                path: vec!["File".into(), "Scripts".into()],
+                scope: APP_SCOPE.into(),
+                defaults: vec![],
+            }
+        })
+        .collect()
+}
+
 /// Canonical shortcut text (`cmd+shift+k`, `Shift+Cmd+K`, `⌘⇧K` → `Cmd+Shift+K`); `None` if it
 /// has no key.
 pub fn normalize(s: &str) -> Option<String> {
@@ -436,7 +458,16 @@ pub struct ShortcutTable {
 
 impl ShortcutTable {
     pub fn build(maps: &Keymaps, ui: &[UiCommand]) -> ShortcutTable {
-        let bindables = bindables(ui);
+        Self::build_with_scripts(maps, ui, &[])
+    }
+
+    /// [`ShortcutTable::build`] with the File ▸ Scripts entries of the scripts `scripts`, listed
+    /// after the other File ▸ Scripts entries.
+    pub fn build_with_scripts(maps: &Keymaps, ui: &[UiCommand], scripts: &[String]) -> ShortcutTable {
+        let mut bindables = bindables(ui);
+        let at = bindables.iter().rposition(|b| b.path.starts_with(&["File".to_string(), "Scripts".to_string()])).map_or(bindables.len(), |i| i + 1);
+        let new: Vec<Bindable> = script_bindables(scripts).into_iter().filter(|s| !bindables.iter().any(|b| b.key == s.key)).collect();
+        bindables.splice(at..at, new);
         let keys = bindables.iter().map(|b| (b.key.clone(), maps.keys_of(b))).collect();
         ShortcutTable { bindables, keys }
     }

crates/engine/src/system/perf.rs

@@ -180,7 +180,7 @@ pub fn large_project(spec: &LargeSpec) -> Project {
             *n += 1;
             layers.push(l);
         }
-        comp.layers = layers;
+        comp.layers = layers.into();
     };
     let others = spec.comps.saturating_sub(1);
     let depth = spec.nest_depth.min(others);
@@ -215,7 +215,7 @@ pub fn large_project(spec: &LargeSpec) -> Project {
         n += 1;
         layers.push(l);
     }
-    main.layers = layers;
+    main.layers = layers.into();
     p.add_item("Main", crate::color::Label::None, None, ItemKind::Comp(Arc::new(main)));
     // `Main` must be the first comp `replace_project` opens: give it the smallest id.
     let main_id = p.items.values().find(|i| i.name == "Main").map(|i| i.id).expect("main");

crates/engine/src/tests.rs

@@ -15,6 +15,7 @@ mod frame_export;
 mod fuzz_open;
 mod history;
 mod import_project;
+mod instance3d;
 mod key_metadata_order;
 mod key_time;
 mod keyframe_text;
@@ -40,6 +41,7 @@ pub(crate) mod roto;
 mod sequence;
 mod session;
 mod settings;
+mod shared_layers;
 mod shortcut_cmds;
 pub(crate) mod stubs;
 mod styles;

crates/engine/src/tests/crypto_pick.rs

@@ -190,7 +190,16 @@ fn rendered_matte_of_pick(s: &mut Session, x: f64, y: f64, scale: f64) -> (Strin
     s.execute_checked("prop.set", json!({"path": format!("effects/#{fx}/matteOnly"), "value": true})).unwrap();
     let (cid, comp) = (s.active_comp_id().unwrap(), s.active_comp().unwrap());
     let layer = &comp.layers[0];
-    let ctx = effectcraft_render::EvalCtx { project: &s.project, comp_id: cid, comp, time: Tick::ZERO, expr: None, footage: None };
+    let ctx = effectcraft_render::EvalCtx {
+        project: &s.project,
+        comp_id: cid,
+        comp,
+        time: Tick::ZERO,
+        expr: None,
+        footage: None,
+        property_overrides: &[],
+        media_overrides: &[],
+    };
     let buf = s.renderer(effectcraft_render::RenderOpts { scale, ..Default::default() }).content_buf(&ctx, layer).unwrap();
     let (px, py) = buf.to_px([x, y]);
     let m = buf.img.get(px.floor() as i64, py.floor() as i64)[0];

crates/engine/src/tests/effects.rs

@@ -550,7 +550,7 @@ fn opening_an_old_project_upgrades_effect_instances() {
             effectcraft_project::ItemKind::Comp(c) => c,
             _ => panic!("not a composition"),
         });
-        let l = comp.layers.iter_mut().find(|l| l.id == LayerId(a)).unwrap();
+        let l = comp.layers.find_mut(|l| l.id == LayerId(a)).unwrap();
         for n in &mut l.props.sub_mut("effects").unwrap().children {
             let Node::Group(g) = n else { continue };
             if g.match_id == "ec.blur.gaussian" {

crates/engine/src/tests/essential.rs

@@ -367,6 +367,128 @@ fn media_replacement_swaps_footage_per_instance() {
     assert!(center(&s, main)[0] > 0.99);
 }
 
+/// #1747: a collapsed precomp with an Essential Property override must keep drawing its nested
+/// layers past the precomp's frame instead of falling back to a flattened, clipped frame.
+#[test]
+fn collapsed_precomp_applies_property_overrides_without_clipping() {
+    struct AddY;
+    impl effectcraft_render::ExprHost for AddY {
+        fn eval(
+            &self,
+            _: &effectcraft_render::EvalCtx,
+            _: &effectcraft_project::Layer,
+            _: &effectcraft_project::Property,
+            value: &effectcraft_keyframe::Value,
+        ) -> Result<effectcraft_keyframe::Value, String> {
+            Ok(match value {
+                effectcraft_keyframe::Value::Vec3([x, y, z]) => effectcraft_keyframe::Value::Vec3([*x, y + 100.0, *z]),
+                _ => value.clone(),
+            })
+        }
+    }
+    let mut s = Session::default();
+    s.execute("comp.new", json!({"name": "Inner", "width": 400, "height": 300, "frameRate": 30, "duration": 2})).unwrap();
+    let inner = s.active_comp_id().unwrap();
+    let box_ = s.execute("layer.newSolid", json!({"name": "Box", "color": "#ffffff", "width": 100, "height": 100})).unwrap()["layer"].as_u64().unwrap();
+    s.execute("prop.set", json!({"layer": box_, "path": "transform/position", "value": [200, 50, 0]})).unwrap();
+    // The source property's expression still runs after the instance override.
+    s.execute("prop.setExpression", json!({"layer": box_, "path": "transform/position", "expression": "value + [0, 100, 0]"})).unwrap();
+    let position = s.execute("essential.addProperty", json!({"layer": box_, "path": "transform/position"})).unwrap()["controls"][0].as_u64().unwrap();
+    s.execute("comp.new", json!({"name": "Outer", "width": 400, "height": 600, "frameRate": 30, "duration": 2})).unwrap();
+    let outer = s.active_comp_id().unwrap();
+    let instance = s.execute("layer.addItem", json!({"item": inner.0})).unwrap()["layer"].as_u64().unwrap();
+    let other = s.execute("layer.addItem", json!({"item": inner.0})).unwrap()["layer"].as_u64().unwrap();
+    s.execute("layer.setSwitch", json!({"layers": [instance, other], "switch": "collapse", "value": true})).unwrap();
+    s.expr = Some(std::sync::Arc::new(AddY));
+    s.execute("layer.select", json!({"layers": [instance]})).unwrap();
+    s.execute("essential.set", json!({"layer": instance, "control": position, "value": [200, -120, 0]})).unwrap();
+    s.execute("layer.select", json!({"layers": [other]})).unwrap();
+    s.execute("essential.set", json!({"layer": other, "control": position, "value": [200, 220, 0]})).unwrap();
+    let img = s.render(outer, Tick::ZERO, RenderOpts::default());
+    // The expression adds 100 px: the overrides give inner y = -20 and 320. The first maps to
+    // outer y = 130 (the precomp is centred at 300) and its 100 px box spans 80..179, 70 px above
+    // the instance's frame (150..449), where a flattened precomp would stop. The second maps to
+    // 470 and spans 420..519, past the bottom.
+    assert!(img.get(200, 100)[3] > 0.99, "the override draws above the nested frame: {:?}", img.get(200, 100));
+    assert!(img.get(200, 90)[3] > 0.99, "the box reaches the top of its overridden bounds");
+    assert!(img.get(200, 500)[3] > 0.99, "the other instance keeps its own override: {:?}", img.get(200, 500));
+    assert!(img.get(200, 200)[3] < 0.01, "nothing is left between the instances");
+}
+
+/// #1747: two collapsed instances of the same comp keep their own source-affecting property
+/// overrides in the layer cache (the nested layers' ids and static values are identical).
+#[test]
+fn collapsed_instances_keep_distinct_property_overrides_in_the_cache() {
+    let mut s = Session::default();
+    s.execute("comp.new", json!({"name": "Card", "width": 64, "height": 64, "frameRate": 30, "duration": 2})).unwrap();
+    let card = s.active_comp_id().unwrap();
+    let solid = s.execute("layer.newSolid", json!({"name": "BG", "color": "#ffffff", "width": 64, "height": 64})).unwrap()["layer"].as_u64().unwrap();
+    s.execute("effect.apply", json!({"layer": solid, "effect": "Fill"})).unwrap();
+    let color = s.execute("essential.addProperty", json!({"layer": solid, "path": "effects/#1/color"})).unwrap()["controls"][0].as_u64().unwrap();
+    s.execute("comp.new", json!({"name": "Main", "width": 200, "height": 100, "frameRate": 30, "duration": 2})).unwrap();
+    let main = s.active_comp_id().unwrap();
+    let a = s.execute("layer.addItem", json!({"item": card.0})).unwrap()["layer"].as_u64().unwrap();
+    let b = s.execute("layer.addItem", json!({"item": card.0})).unwrap()["layer"].as_u64().unwrap();
+    s.execute("layer.setSwitch", json!({"layers": [a, b], "switch": "collapse", "value": true})).unwrap();
+    s.execute("prop.set", json!({"layer": a, "path": "transform/position", "value": [60, 50, 0]})).unwrap();
+    s.execute("prop.set", json!({"layer": b, "path": "transform/position", "value": [140, 50, 0]})).unwrap();
+    s.execute("layer.select", json!({"layers": [a]})).unwrap();
+    s.execute("essential.set", json!({"layer": a, "control": color, "value": [1.0, 0.0, 0.0, 1.0]})).unwrap();
+    s.execute("layer.select", json!({"layers": [b]})).unwrap();
+    s.execute("essential.set", json!({"layer": b, "control": color, "value": [0.0, 0.0, 1.0, 1.0]})).unwrap();
+    let img = s.render(main, Tick::ZERO, RenderOpts::default());
+    let left = img.get(60, 50);
+    let right = img.get(140, 50);
+    assert!(left[0] > 0.99 && left[2] < 0.01, "left instance is red: {left:?}");
+    assert!(right[2] > 0.99 && right[0] < 0.01, "right instance is blue: {right:?}");
+}
+
+/// #1747 with Media Replacement: the replacement footage and the position override both apply
+/// while the precomp stays collapsed, so the box is blue and still draws above the frame.
+#[test]
+fn collapsed_precomp_applies_media_replacement_without_clipping() {
+    struct Colors;
+    impl crate::render::FootageSource for Colors {
+        fn frame(&self, _: ItemId, f: &effectcraft_project::Footage, _: Tick) -> Option<std::sync::Arc<effectcraft_raster::Image>> {
+            let c = if f.path.contains("blue") { [0.0, 0.0, 1.0, 1.0] } else { [1.0, 0.0, 0.0, 1.0] };
+            Some(std::sync::Arc::new(effectcraft_raster::Image::filled(100, 100, c)))
+        }
+    }
+    let mut s = Session { footage: std::sync::Arc::new(Colors), ..Default::default() };
+    let footage = |path: &str| effectcraft_project::Footage {
+        path: path.into(),
+        kind: effectcraft_project::FootageKind::Still,
+        width: 100,
+        height: 100,
+        has_video: true,
+        ..Default::default()
+    };
+    let (red, blue) = s
+        .edit("test", None, |proj, _| {
+            let red = proj.add_item("red.png", Default::default(), None, effectcraft_project::ItemKind::Footage(footage("red.png")));
+            let blue = proj.add_item("blue.png", Default::default(), None, effectcraft_project::ItemKind::Footage(footage("blue.png")));
+            Ok((red, blue))
+        })
+        .unwrap();
+    s.execute("comp.new", json!({"name": "Inner", "width": 400, "height": 300, "frameRate": 30, "duration": 2})).unwrap();
+    let inner = s.active_comp_id().unwrap();
+    let clip = s.execute("layer.addItem", json!({"item": red.0})).unwrap()["layer"].as_u64().unwrap();
+    s.execute("prop.set", json!({"layer": clip, "path": "transform/position", "value": [200, 50, 0]})).unwrap();
+    let media = s.execute("essential.addMedia", json!({"layer": clip})).unwrap()["control"].as_u64().unwrap();
+    let position = s.execute("essential.addProperty", json!({"layer": clip, "path": "transform/position"})).unwrap()["controls"][0].as_u64().unwrap();
+    s.execute("comp.new", json!({"name": "Outer", "width": 400, "height": 600, "frameRate": 30, "duration": 2})).unwrap();
+    let outer = s.active_comp_id().unwrap();
+    let instance = s.execute("layer.addItem", json!({"item": inner.0})).unwrap()["layer"].as_u64().unwrap();
+    s.execute("layer.setSwitch", json!({"layers": [instance], "switch": "collapse", "value": true})).unwrap();
+    s.execute("layer.select", json!({"layers": [instance]})).unwrap();
+    s.execute("essential.set", json!({"layer": instance, "control": position, "value": [200, -20, 0]})).unwrap();
+    s.execute("essential.set", json!({"layer": instance, "control": media, "item": blue.0})).unwrap();
+    let img = s.render(outer, Tick::ZERO, RenderOpts::default());
+    let above = img.get(200, 100);
+    assert!(above[2] > 0.99 && above[0] < 0.01, "the replacement media is blue above the frame: {above:?}");
+    assert!(img.get(200, 200)[3] < 0.01, "the collapsed box is not clipped at the nested frame");
+}
+
 /// Responsive Design — Time: stretching a precomp keeps its protected regions at their
 /// original speed; the unprotected parts absorb the stretch.
 #[test]

crates/engine/src/tests/essential_more.rs

@@ -2,6 +2,7 @@
 
 use effectcraft_keyframe::Value as KV;
 use effectcraft_project::essential::{self, ControlType};
+use effectcraft_time::Tick;
 use serde_json::json;
 
 use crate::{Event, Session};
@@ -102,3 +103,33 @@ fn open_in_essential_graphics_sets_the_primary_comp() {
     );
     assert_eq!(s.execute("essential.list", json!({})).unwrap()["name"], "A");
 }
+
+/// #1747: through a collapsed precomp, a Text override and a Font override of the same Source
+/// Text both apply: the Font merges into the overridden text, as `essential::with_overrides`
+/// does on the flattened path, instead of one entry replacing the other.
+#[test]
+fn collapsed_instance_merges_text_and_font_overrides() {
+    let mut s = Session::default();
+    s.execute("comp.new", json!({"name": "Title", "width": 64, "height": 64, "frameRate": 30, "duration": 1})).unwrap();
+    let title = s.active_comp_id().unwrap();
+    let text = s.execute("layer.newText", json!({"text": "Hello"})).unwrap()["layer"].as_u64().unwrap();
+    let body = s.execute("essential.addProperty", json!({"layer": text, "path": "text/sourceText"})).unwrap()["controls"][0].as_u64().unwrap();
+    let font = s.execute("essential.addProperty", json!({"layer": text, "path": "text/sourceText", "as": "font"})).unwrap()["controls"][0].as_u64().unwrap();
+    s.execute("comp.new", json!({"name": "Main", "width": 64, "height": 64, "frameRate": 30, "duration": 1})).unwrap();
+    let main = s.active_comp_id().unwrap();
+    let inst = s.execute("layer.addItem", json!({"item": title.0})).unwrap()["layer"].as_u64().unwrap();
+    s.execute("layer.setSwitch", json!({"layers": [inst], "switch": "collapse", "value": true})).unwrap();
+    s.execute("essential.set", json!({"layer": inst, "control": body, "value": "Bye"})).unwrap();
+    s.execute("essential.set", json!({"layer": inst, "control": font, "value": {"font": "Serif Test", "size": 40}})).unwrap();
+    // Evaluate the nested text in the collapsed instance's context, as the renderer does.
+    let r = effectcraft_render::Renderer::new(&s.project, &*s.footage, crate::render::RenderOpts::default());
+    let ctx = effectcraft_render::EvalCtx::new(&s.project, main, s.project.comp(main).unwrap(), Tick::ZERO);
+    let layer = ctx.comp.layer(effectcraft_project::LayerId(inst)).unwrap();
+    let collapsed = r.collapsed(&ctx, layer).expect("the instance collapses");
+    let (_, nctx) = r.collapse_into(&ctx, layer, &collapsed, 1.0).expect("a nested context");
+    let src = nctx.comp.layer(effectcraft_project::LayerId(text)).unwrap();
+    match nctx.value(src, src.props.prop("text/sourceText").unwrap()) {
+        KV::Text(d) => assert_eq!((d.text.as_str(), d.font.as_str(), d.size), ("Bye", "Serif Test", 40.0)),
+        o => panic!("{o:?}"),
+    }
+}

crates/engine/src/tests/frame_export.rs

@@ -164,3 +164,69 @@ fn copy_frame_hands_the_rendered_frame_to_the_frontend() {
     assert!(Session::default().execute("comp.copyFrame", json!({})).is_err());
     assert!(crate::menus::entries().iter().any(|(path, e)| e.command == "comp.copyFrame" && path.first().map(String::as_str) == Some("Composition")));
 }
+
+#[test]
+fn save_frame_as_png_preserves_alpha_channel() {
+    let mut s = Session::default();
+    s.execute("comp.new", json!({"name": "AlphaComp", "width": 32, "height": 32, "frameRate": 24, "duration": 1})).unwrap();
+    let red = s.execute("layer.newSolid", json!({"name": "Red", "color": "#ff0000", "width": 16, "height": 16})).unwrap()["layer"].as_u64().unwrap();
+    s.execute("prop.set", json!({"layer": red, "path": "transform/position", "value": [8, 8, 0]})).unwrap();
+    let dir = out_dir("frame-png-alpha");
+    let path = dir.join("alpha.png").to_string_lossy().to_string();
+
+    s.execute("comp.saveFrameAs", json!({"path": path})).unwrap();
+    let img = image::load_from_memory(&std::fs::read(&path).unwrap()).unwrap().to_rgba8();
+    assert_eq!((img.width(), img.height()), (32, 32));
+    let solid_px = img.get_pixel(8, 8);
+    assert_eq!(solid_px[3], 255, "solid region must be opaque: {solid_px:?}");
+    assert_eq!(solid_px[0], 255);
+    let empty_px = img.get_pixel(24, 24);
+    assert_eq!(empty_px[3], 0, "outside solid region must have alpha 0: {empty_px:?}");
+
+    let flat_path = dir.join("flat.png").to_string_lossy().to_string();
+    s.execute_checked("comp.saveFrameAs", json!({"path": flat_path, "transparent": false})).unwrap();
+    let flat_img = image::load_from_memory(&std::fs::read(&flat_path).unwrap()).unwrap().to_rgba8();
+    let flat_empty_px = flat_img.get_pixel(24, 24);
+    assert_eq!(flat_empty_px[3], 255, "transparent: false must composite over background: {flat_empty_px:?}");
+}
+
+#[test]
+fn save_frame_as_queued_respects_frame_default_template() {
+    let mut s = Session::default();
+    s.execute("comp.new", json!({"name": "Comp", "width": 32, "height": 32, "frameRate": 24, "duration": 1})).unwrap();
+
+    // Default Still template is "PNG Sequence" (Channels::Rgb)
+    let r = s.execute_checked("comp.saveFrameAs", json!({"queue": true})).unwrap();
+    assert_eq!(r["queued"], true);
+    let it = s.project.render_queue.last().unwrap();
+    assert_eq!(it.output.name, "PNG Sequence");
+    assert_eq!(it.output.channels, effectcraft_project::render_queue::Channels::Rgb);
+
+    // Test undo and redo of queuing a frame
+    s.execute("edit.undo", json!({})).unwrap();
+    assert!(s.project.render_queue.is_empty());
+    s.execute("edit.redo", json!({})).unwrap();
+    let it = s.project.render_queue.last().unwrap();
+    assert_eq!(it.output.name, "PNG Sequence");
+
+    // Explicit transparent: false forces Channels::Rgb
+    s.execute_checked("comp.saveFrameAs", json!({"queue": true, "transparent": false})).unwrap();
+    let it = s.project.render_queue.last().unwrap();
+    assert_eq!(it.output.channels, effectcraft_project::render_queue::Channels::Rgb);
+
+    // When Frame Default is set to an RGBA template, it is respected
+    s.execute_checked("renderQueue.setTemplateDefault", json!({"kind": "outputModule", "slot": "still", "name": "PNG Sequence with Alpha"})).unwrap();
+    s.execute_checked("comp.saveFrameAs", json!({"queue": true})).unwrap();
+    let it = s.project.render_queue.last().unwrap();
+    assert_eq!(it.output.name, "PNG Sequence with Alpha");
+    assert_eq!(it.output.channels, effectcraft_project::render_queue::Channels::Rgba);
+
+    // Passing transparent: false forces Channels::Rgb even with an RGBA template
+    s.execute_checked("comp.saveFrameAs", json!({"queue": true, "transparent": false})).unwrap();
+    let it = s.project.render_queue.last().unwrap();
+    assert_eq!(it.output.channels, effectcraft_project::render_queue::Channels::Rgb);
+
+    // With JPEG Sequence as Frame Default (non-alpha format), queue succeeds without error
+    s.execute_checked("renderQueue.setTemplateDefault", json!({"kind": "outputModule", "slot": "still", "name": "JPEG Sequence"})).unwrap();
+    assert!(s.execute_checked("comp.saveFrameAs", json!({"queue": true})).is_ok());
+}

crates/engine/src/tests/instance3d.rs

@@ -0,0 +1,257 @@
+//! Create 3D Layer Instance (Layer ▸ Create): a comp-sized solid at the top of the layer stack
+//! with a 3D Layer Instance effect referencing the selected 3D model layer — a 2D copy of its
+//! render that 2D effects can be applied to (behaviour, pixels, undo/redo, serde).
+
+use std::sync::Arc;
+
+use effectcraft_keyframe::Value as KV;
+use effectcraft_project::{Footage, FootageKind, GroupKind, ItemId, Layer, LayerId, Project};
+use effectcraft_render::{FootageSource, RenderOpts};
+use effectcraft_time::{FrameRate, Tick};
+use serde_json::json;
+
+use crate::{Importer, Session};
+
+fn session() -> Session {
+    let mut s = Session { footage: Arc::new(DiskModels), importer: Some(Arc::new(ModelImporter)), ..Default::default() };
+    s.execute("comp.new", json!({"name": "Scene", "width": 640, "height": 360, "frameRate": 30, "duration": 2})).unwrap();
+    s
+}
+
+fn cid(s: &Session) -> ItemId {
+    s.active_comp_id().unwrap()
+}
+
+fn layer_in(s: &Session, comp: ItemId, id: u64) -> Layer {
+    s.project.comp(comp).unwrap().layer(LayerId(id)).unwrap().clone()
+}
+
+fn px(img: &effectcraft_raster::Image, x: u32, y: u32) -> [f32; 4] {
+    img.data[(y * img.width + x) as usize]
+}
+
+fn close(a: &effectcraft_raster::Image, b: &effectcraft_raster::Image, tol: f32) -> bool {
+    a.data.iter().zip(b.data.iter()).all(|(p, q)| p.iter().zip(q.iter()).all(|(x, y)| (x - y).abs() <= tol))
+}
+
+struct DiskModels;
+
+impl FootageSource for DiskModels {
+    fn frame(&self, _: ItemId, _: &Footage, _: Tick) -> Option<Arc<effectcraft_raster::Image>> {
+        None
+    }
+    fn model(&self, _: ItemId, f: &Footage) -> Option<Arc<effectcraft_model::Model>> {
+        let bytes = std::fs::read(&f.path).ok()?;
+        effectcraft_model::load(&f.path, &bytes, &|_| None).ok().map(Arc::new)
+    }
+}
+
+struct ModelImporter;
+
+impl Importer for ModelImporter {
+    fn probe(&self, path: &str) -> Result<Footage, String> {
+        effectcraft_model::format_of(path).ok_or("not a model")?;
+        Ok(Footage { path: path.into(), kind: FootageKind::Model, frame_rate: FrameRate::FPS_30, codec: "glTF".into(), ..Default::default() })
+    }
+}
+
+/// A red triangle in the Z = 0 plane (buffer embedded as a data URI).
+const TRIANGLE: &str = r#"{
+  "asset": {"version": "2.0"},
+  "scenes": [{"nodes": [0]}],
+  "nodes": [{"mesh": 0}],
+  "meshes": [{"primitives": [{"attributes": {"POSITION": 0, "NORMAL": 1}, "material": 0}]}],
+  "materials": [{"pbrMetallicRoughness": {"baseColorFactor": [1.0, 0.0, 0.0, 1.0]}}],
+  "buffers": [{"byteLength": 72, "uri": "data:application/octet-stream;base64,AACAvwAAgL8AAAAAAACAPwAAgL8AAAAAAAAAAAAAgD8AAAAAAAAAAAAAAAAAAIA/AAAAAAAAAAAAAIA/AAAAAAAAAAAAAIA/"}],
+  "bufferViews": [
+    {"buffer": 0, "byteOffset": 0, "byteLength": 36},
+    {"buffer": 0, "byteOffset": 36, "byteLength": 36}
+  ],
+  "accessors": [
+    {"bufferView": 0, "componentType": 5126, "type": "VEC3", "count": 3, "min": [-1.0, -1.0, 0.0], "max": [1.0, 1.0, 0.0]},
+    {"bufferView": 1, "componentType": 5126, "type": "VEC3", "count": 3}
+  ]
+}"#;
+
+fn triangle_model(s: &mut Session) -> u64 {
+    let dir = std::env::temp_dir().join(format!("ec-instance3d-{}", std::process::id()));
+    std::fs::create_dir_all(&dir).unwrap();
+    let path = dir.join("Triangle.gltf");
+    std::fs::write(&path, TRIANGLE).unwrap();
+    s.execute("layer.newModel", json!({"path": path.to_string_lossy(), "name": "Triangle"})).unwrap()["layer"].as_u64().unwrap()
+}
+
+#[test]
+fn instance3d_creates_a_2d_copy_of_the_model() {
+    let mut s = session();
+    let model = triangle_model(&mut s);
+    // The model renders through the comp's camera.
+    let before = s.render(cid(&s), Tick::ZERO, RenderOpts::default());
+    assert!(px(&before, 320, 180)[3] > 0.9, "the model covers the centre: {:?}", px(&before, 320, 180));
+    assert!(px(&before, 4, 4)[3] < 0.1, "the comp is transparent around it: {:?}", px(&before, 4, 4));
+    // Create 3D Layer Instance.
+    s.execute("layer.select", json!({"layers": [model]})).unwrap();
+    let r = s.execute("layer.create", json!({"op": "instance3d"})).unwrap();
+    let solid = r["layers"][0].as_u64().unwrap();
+    let comp = cid(&s);
+    let l = layer_in(&s, comp, solid);
+    assert_eq!(l.name, "Triangle Instance");
+    assert_eq!(s.active_comp().unwrap().layers[0].id.0, solid, "at the top of the layer stack");
+    // A 3D Layer Instance effect referencing the 3D layer.
+    let g = l.effects().unwrap().groups().next().unwrap().clone();
+    assert!(matches!(&g.kind, GroupKind::Effect { effect } if effect == "ec.3d.instance3d"), "{:?}", g.kind);
+    assert_eq!(g.get("layer").unwrap().value, KV::Layer(Some(model)));
+    // The model is switched off, the copy selected.
+    assert!(!layer_in(&s, comp, model).switches.video, "the referenced 3D layer is off, as After Effects does");
+    assert_eq!(s.state.selected_layers, vec![LayerId(solid)]);
+    // The comp renders the same through the copy: a 2D copy of the 3D layer, transparent
+    // around it.
+    let after = s.render(comp, Tick::ZERO, RenderOpts::default());
+    assert!(close(&before, &after, 2e-2), "the copy shows the model:\n{:?}\n{:?}", px(&before, 320, 180), px(&after, 320, 180));
+    assert!(px(&after, 320, 180)[3] > 0.9 && px(&after, 4, 4)[3] < 0.1, "{:?} {:?}", px(&after, 320, 180), px(&after, 4, 4));
+    // Undo removes the copy and switches the model back on; redo returns it.
+    s.execute("edit.undo", json!({})).unwrap();
+    assert!(s.active_comp().unwrap().layer(LayerId(solid)).is_none());
+    assert!(layer_in(&s, comp, model).switches.video);
+    s.execute("edit.redo", json!({})).unwrap();
+    assert!(s.active_comp().unwrap().layer(LayerId(solid)).is_some());
+    assert!(!layer_in(&s, comp, model).switches.video);
+    // Serde round-trips the layer parameter.
+    let j = serde_json::to_string(&*s.project).unwrap();
+    let back: Project = serde_json::from_str(&j).unwrap();
+    assert_eq!(back, *s.project);
+    // 2D effects can be applied to the copy (the model layer itself takes none): Fill in blue
+    // recolours the triangle.
+    s.execute("effect.apply", json!({"layer": solid, "effect": "ec.generate.fill"})).unwrap();
+    s.execute("prop.set", json!({"layer": solid, "path": "effects/#2/color", "value": [0.0, 0.0, 1.0, 1.0]})).unwrap();
+    let with_fx = s.render(comp, Tick::ZERO, RenderOpts::default());
+    let p = px(&with_fx, 320, 180);
+    assert!(p[2] > 0.9 && p[0] < 0.1, "the fill recolours the copy: {p:?}");
+}
+
+#[test]
+fn instance3d_also_takes_3d_primitives() {
+    let mut s = session();
+    let prim = s.execute("layer.new3dPrimitive", json!({"kind": "cube", "width": 200, "height": 200, "depth": 200})).unwrap()["layer"].as_u64().unwrap();
+    let before = s.render(cid(&s), Tick::ZERO, RenderOpts::default());
+    let r = s.execute("layer.create", json!({"op": "instance3d", "layers": [prim]})).unwrap();
+    let solid = r["layers"][0].as_u64().unwrap();
+    let l = layer_in(&s, cid(&s), solid);
+    assert_eq!(l.name, "Cube Instance");
+    assert!(!layer_in(&s, cid(&s), prim).switches.video);
+    let after = s.render(cid(&s), Tick::ZERO, RenderOpts::default());
+    assert!(close(&before, &after, 2e-2), "the copy shows the cube");
+}
+
+#[test]
+fn instance3d_needs_a_3d_layer() {
+    let mut s = session();
+    let solid = s.execute("layer.newSolid", json!({"color": "#808080", "width": 100, "height": 100})).unwrap()["layer"].as_u64().unwrap();
+    let err = s.execute_checked("layer.create", json!({"op": "instance3d", "layers": [solid]}));
+    assert!(err.is_err());
+    let text = s.execute("layer.newText", json!({"text": "hi"})).unwrap()["layer"].as_u64().unwrap();
+    assert!(s.execute_checked("layer.create", json!({"op": "instance3d", "layers": [text]})).is_err());
+    // A 3D-switched text layer is not a model layer either (it has 2D pixels of its own).
+    s.execute("layer.setSwitch", json!({"layers": [text], "switch": "threeD", "value": true})).unwrap();
+    assert!(s.execute_checked("layer.create", json!({"op": "instance3d", "layers": [text]})).is_err());
+}
+
+#[test]
+fn instance3d_creates_every_selected_copy_in_one_undo() {
+    let mut s = session();
+    let a = s.execute("layer.new3dPrimitive", json!({"kind": "cube", "width": 120, "height": 120, "depth": 120})).unwrap()["layer"].as_u64().unwrap();
+    let b = s.execute("layer.new3dPrimitive", json!({"kind": "cube", "width": 120, "height": 120, "depth": 120})).unwrap()["layer"].as_u64().unwrap();
+    let r = s.execute("layer.create", json!({"op": "instance3d", "layers": [a, b]})).unwrap();
+    let copies = r["layers"].as_array().unwrap();
+    assert_eq!(copies.len(), 2);
+    let (ia, ib) = (copies[0].as_u64().unwrap(), copies[1].as_u64().unwrap());
+    let comp = cid(&s);
+    assert_ne!(ia, ib);
+    assert_ne!(layer_in(&s, comp, ia).name, layer_in(&s, comp, ib).name, "each copy has a name of its own");
+    // Both sources are off, both copies selected, above their sources in the stack.
+    assert!(!layer_in(&s, comp, a).switches.video && !layer_in(&s, comp, b).switches.video);
+    let mut sel = s.state.selected_layers.clone();
+    let mut want = vec![LayerId(ia), LayerId(ib)];
+    sel.sort_by_key(|l| l.0);
+    want.sort_by_key(|l| l.0);
+    assert_eq!(sel, want);
+    let c = s.active_comp().unwrap();
+    let pos = |id: u64| c.layers.iter().position(|l| l.id.0 == id).unwrap();
+    assert!(pos(ia) < pos(a) && pos(ib) < pos(b), "the copies sit above their sources");
+    // One undo removes both copies and switches both models back on; one redo returns them.
+    s.execute("edit.undo", json!({})).unwrap();
+    let c = s.active_comp().unwrap();
+    assert!(c.layer(LayerId(ia)).is_none() && c.layer(LayerId(ib)).is_none(), "one undo removes every instance");
+    assert!(layer_in(&s, comp, a).switches.video && layer_in(&s, comp, b).switches.video);
+    s.execute("edit.redo", json!({})).unwrap();
+    let c = s.active_comp().unwrap();
+    assert!(c.layer(LayerId(ia)).is_some() && c.layer(LayerId(ib)).is_some(), "one redo returns every instance");
+    assert!(!layer_in(&s, comp, a).switches.video && !layer_in(&s, comp, b).switches.video);
+}
+
+#[test]
+fn instance3d_in_a_mixed_selection_only_takes_the_models() {
+    let mut s = session();
+    let model = triangle_model(&mut s);
+    let solid = s.execute("layer.newSolid", json!({"color": "#808080", "width": 100, "height": 100})).unwrap()["layer"].as_u64().unwrap();
+    let r = s.execute("layer.create", json!({"op": "instance3d", "layers": [model, solid]})).unwrap();
+    let copies = r["layers"].as_array().unwrap();
+    assert_eq!(copies.len(), 1, "only the model gets a copy: {r}");
+    let copy = copies[0].as_u64().unwrap();
+    let comp = cid(&s);
+    assert!(!layer_in(&s, comp, model).switches.video, "the model is switched off");
+    assert!(layer_in(&s, comp, solid).switches.video, "the plain solid is untouched");
+    let skipped = r["skipped"].as_array().unwrap();
+    assert_eq!(skipped.len(), 1);
+    assert!(skipped[0].as_str().unwrap().contains("not a 3D model layer"), "{skipped:?}");
+    // The copy references the model, not the solid.
+    let l = layer_in(&s, comp, copy);
+    let g = l.effects().unwrap().groups().next().unwrap().clone();
+    assert_eq!(g.get("layer").unwrap().value, KV::Layer(Some(model)));
+}
+
+#[test]
+fn instance3d_shows_nothing_outside_the_source_layer_range() {
+    let mut s = session();
+    let model = triangle_model(&mut s);
+    // The model's range ends at 1 s; the comp runs to 2 s.
+    let comp = cid(&s);
+    s.edit("trim", None, |p, _| {
+        p.comp_mut(comp).unwrap().layer_mut(LayerId(model)).unwrap().out_point = Tick::from_seconds_f64(1.0);
+        Ok(())
+    })
+    .unwrap();
+    s.execute("layer.select", json!({"layers": [model]})).unwrap();
+    let r = s.execute("layer.create", json!({"op": "instance3d"})).unwrap();
+    let _copy = r["layers"][0].as_u64().unwrap();
+    // Inside the model's range the copy shows it, transparent around it.
+    let inside = s.render(comp, Tick::from_seconds_f64(0.5), RenderOpts::default());
+    assert!(px(&inside, 320, 180)[3] > 0.9, "the copy shows the model: {:?}", px(&inside, 320, 180));
+    // After its out point the source has nothing to read: the copy is transparent.
+    let outside = s.render(comp, Tick::from_seconds_f64(1.5), RenderOpts::default());
+    assert!(outside.data.iter().all(|p| p[3] < 1e-3), "transparent after the source's out point: {:?}", px(&outside, 320, 180));
+}
+
+#[test]
+fn instance3d_keeps_the_copy_visible_when_the_source_is_soloed() {
+    let mut s = session();
+    let model = triangle_model(&mut s);
+    let comp = cid(&s);
+    // Solo the model, then create the instance: any_solo hides non-soloed layers and the
+    // source's video goes off, so the copy has to take the Solo over.
+    s.edit("solo", None, |p, _| {
+        p.comp_mut(comp).unwrap().layer_mut(LayerId(model)).unwrap().switches.solo = true;
+        Ok(())
+    })
+    .unwrap();
+    let before = s.render(comp, Tick::ZERO, RenderOpts::default());
+    assert!(px(&before, 320, 180)[3] > 0.9, "the soloed model shows: {:?}", px(&before, 320, 180));
+    s.execute("layer.select", json!({"layers": [model]})).unwrap();
+    let r = s.execute("layer.create", json!({"op": "instance3d"})).unwrap();
+    let solid = r["layers"][0].as_u64().unwrap();
+    assert!(layer_in(&s, comp, solid).switches.solo, "the copy takes the source's Solo switch");
+    assert!(!layer_in(&s, comp, model).switches.video, "the source keeps its video off");
+    let after = s.render(comp, Tick::ZERO, RenderOpts::default());
+    assert!(px(&after, 320, 180)[3] > 0.9, "the soloed copy shows the model: {:?}", px(&after, 320, 180));
+    assert!(close(&before, &after, 2e-2), "the comp renders the same through the copy:\n{:?}\n{:?}", px(&before, 320, 180), px(&after, 320, 180));
+}

crates/engine/src/tests/menu_cmds.rs

@@ -1103,6 +1103,66 @@ fn transform_commands_keep_depth_and_follow_separated_dimensions() {
     assert_eq!(pos(&s, b)[..2], [200.0, 100.0], "the 200×100 solid's centre");
 }
 
+/// The layer's painted bounds mapped to comp space — what the viewer shows.
+fn seen_bounds(s: &Session, lid: u64) -> [f64; 4] {
+    let cid = s.active_comp_id().unwrap();
+    let comp = s.project.comp(cid).unwrap().clone();
+    let layer = comp.layer(effectcraft_project::LayerId(lid)).unwrap();
+    let ectx = effectcraft_render::EvalCtx::new(&s.project, cid, &comp, s.time());
+    let b = effectcraft_render::content_bounds(&ectx, layer).expect("painted bounds");
+    let m = ectx.layer_to_comp(layer).0;
+    let corners = [[b[0], b[1]], [b[2], b[1]], [b[2], b[3]], [b[0], b[3]]];
+    let pts: Vec<[f64; 2]> = corners
+        .iter()
+        .map(|p| {
+            let q = m.apply(effectcraft_geom::vec2(p[0], p[1]));
+            [q.x, q.y]
+        })
+        .collect();
+    let (mut x0, mut y0, mut x1, mut y1) = (f64::INFINITY, f64::INFINITY, f64::NEG_INFINITY, f64::NEG_INFINITY);
+    for p in &pts {
+        x0 = x0.min(p[0]);
+        y0 = y0.min(p[1]);
+        x1 = x1.max(p[0]);
+        y1 = y1.max(p[1]);
+    }
+    [x0, y0, x1, y1]
+}
+
+#[test]
+fn fit_to_comp_fills_the_comp_with_shape_and_text_bounds() {
+    let mut s = comp();
+    let close = |x: f64, y: f64| (x - y).abs() < 1e-6;
+    // A shape or text layer has no source item: fit sizes it by its painted bounds, anchored at
+    // the bounds' centre, so what the viewer shows fills the frame (#2198).
+    let a = s.execute("layer.newShape", json!({"kind": "rect", "size": [180, 80]})).unwrap()["layer"].as_u64().unwrap();
+    s.execute("layer.transform", json!({"layers": [a], "op": "fit"})).unwrap();
+    let seen = seen_bounds(&s, a);
+    assert!(close(seen[0], 0.0) && close(seen[1], 0.0) && close(seen[2], 640.0) && close(seen[3], 360.0), "the rect's painted bounds fill the comp: {seen:?}");
+
+    let t = s.execute("layer.newText", json!({"text": "Title", "size": 80})).unwrap()["layer"].as_u64().unwrap();
+    s.execute("layer.transform", json!({"layers": [t], "op": "fit"})).unwrap();
+    let seen = seen_bounds(&s, t);
+    assert!(close(seen[0], 0.0) && close(seen[1], 0.0) && close(seen[2], 640.0) && close(seen[3], 360.0), "the text's painted bounds fill the comp: {seen:?}");
+
+    // fitWidth spans the comp's width and centres vertically.
+    for lid in [a, t] {
+        s.execute("layer.transform", json!({"layers": [lid], "op": "fitWidth"})).unwrap();
+        let seen = seen_bounds(&s, lid);
+        assert!(close(seen[0], 0.0) && close(seen[2], 640.0), "fitWidth spans the comp width: {seen:?}");
+        assert!(close((seen[1] + seen[3]) / 2.0, 180.0), "fitWidth centres vertically: {seen:?}");
+    }
+}
+
+#[test]
+fn fit_to_comp_refuses_a_scale_that_overflows() {
+    let mut s = comp();
+    let a = s.execute("layer.newShape", json!({"kind": "rect", "size": [1e-305, 80]})).unwrap()["layer"].as_u64().unwrap();
+    let before = s.project.clone();
+    assert!(s.execute("layer.transform", json!({"layers": [a], "op": "fit"})).is_err(), "an infinite scale is refused");
+    assert_eq!(s.project, before, "nothing was written");
+}
+
 #[test]
 fn duplicated_and_pasted_layers_keep_their_links() {
     let mut s = comp();
@@ -1423,6 +1483,68 @@ fn key_selection_toggles_and_skips_locked_layers_and_hold_restores_bezier() {
     assert!(s.state.selected_keys.is_empty());
 }
 
+#[test]
+fn muting_keys_skips_them_in_the_timeline_value_and_undoes() {
+    let mut s = comp();
+    let a = solid(&mut s, "#ff0000");
+    for (t, v) in [(0.0, 0.0), (1.0, 100.0), (2.0, 300.0)] {
+        s.execute("prop.addKey", json!({"layer": a, "path": "transform/opacity", "time": t, "value": v})).unwrap();
+    }
+    let value_at = |s: &Session, t: f64| layer(s, a).props.prop("transform/opacity").unwrap().value_at(Tick::from_seconds_f64(t)).as_f64();
+    let select = |s: &mut Session| s.execute("keys.select", json!({"keys": [{"layer": a, "path": "transform/opacity", "time": 1.0}]})).unwrap();
+    select(&mut s);
+    let before = value_at(&s, 0.5);
+    s.execute("keys.setMuted", json!({"muted": true})).unwrap();
+    assert!(layer(&s, a).props.prop("transform/opacity").unwrap().keys[1].muted);
+    // The muted key no longer bends the 0 → 300 segment.
+    assert!((value_at(&s, 0.5) - 75.0).abs() < 1e-6);
+    assert!((value_at(&s, 1.5) - 225.0).abs() < 1e-6);
+    s.undo();
+    assert!(!layer(&s, a).props.prop("transform/opacity").unwrap().keys[1].muted);
+    assert!((value_at(&s, 0.5) - before).abs() < 1e-6);
+    // The same command unmutes.
+    select(&mut s);
+    s.execute("keys.setMuted", json!({"muted": true})).unwrap();
+    s.execute("keys.setMuted", json!({"muted": false})).unwrap();
+    assert!(!layer(&s, a).props.prop("transform/opacity").unwrap().keys[1].muted);
+}
+
+/// Both Animation-menu rows mute and unmute through `Session::execute`, and undo/redo work.
+#[test]
+fn mute_and_unmute_keyframes_menu_rows_work_and_undo() {
+    fn rows(nodes: &[crate::menus::MenuNode], out: &mut Vec<(String, Value)>) {
+        for n in nodes {
+            match n {
+                crate::menus::MenuNode::Item(e) if e.command == "keys.setMuted" => out.push((e.label.clone(), e.params.clone())),
+                crate::menus::MenuNode::Submenu { children, .. } => rows(children, out),
+                _ => {}
+            }
+        }
+    }
+    let mut menu = vec![];
+    rows(&crate::menus::parse(crate::menus::TREE, false).unwrap(), &mut menu);
+    assert_eq!(menu.iter().map(|(l, _)| l.as_str()).collect::<Vec<_>>(), ["Mute Keyframes", "Unmute Keyframes"], "{menu:?}");
+
+    let mut s = comp();
+    let a = solid(&mut s, "#ff0000");
+    for (t, v) in [(0.0, 0.0), (1.0, 100.0)] {
+        s.execute("prop.addKey", json!({"layer": a, "path": "transform/opacity", "time": t, "value": v})).unwrap();
+    }
+    let muted = |s: &Session| layer(s, a).props.prop("transform/opacity").unwrap().keys[1].muted;
+    s.execute("keys.select", json!({"keys": [{"layer": a, "path": "transform/opacity", "time": 1.0}]})).unwrap();
+    let run = |s: &mut Session, params: &Value| {
+        s.execute("keys.setMuted", if params.is_null() { json!({}) } else { params.clone() }).unwrap();
+    };
+    run(&mut s, &menu[0].1);
+    assert!(muted(&s));
+    s.undo();
+    assert!(!muted(&s));
+    s.redo();
+    assert!(muted(&s));
+    run(&mut s, &menu[1].1);
+    assert!(!muted(&s));
+}
+
 #[test]
 fn transform_drags_apply_their_whole_offset_to_the_keys_they_started_with() {
     let mut s = comp();

crates/engine/src/tests/proxy.rs

@@ -1,6 +1,6 @@
 //! Proxies (Set Proxy, Use Proxy, Proxy Use render settings, comp proxies, Create Proxy) and
-//! Interpret Footage (fields, pixel aspect, alpha guess / invert, linear light), rendered through
-//! a synthetic footage source.
+//! Interpret Footage (fields, pixel aspect, alpha guess / invert, linear light, Cineon Settings),
+//! rendered through a synthetic footage source.
 
 use std::sync::Arc;
 
@@ -36,6 +36,12 @@ fn file_px(path: &str, x: u32, y: u32) -> [f32; 4] {
         "matte_black.png" => [0.0, 0.5, 0.0, 0.5],
         "matte_white.png" => [0.5, 1.0, 0.5, 0.5],
         "half.png" => [1.0, 1.0, 1.0, 0.25],
+        // A log film scan: code values 95, 685, 400 and 1023 across, as the DPX reader hands
+        // them out (code / 1023).
+        "scan.dpx" | "plate.dpx" => {
+            let v = [95.0, 685.0, 400.0, 1023.0][x.min(3) as usize] / 1023.0;
+            [v, v, v, 1.0]
+        }
         _ => {
             let _ = x;
             [1.0, 1.0, 1.0, 1.0]
@@ -47,7 +53,7 @@ fn size_of(path: &str) -> (u32, u32) {
     match std::path::Path::new(path).file_name().and_then(std::ffi::OsStr::to_str).unwrap_or("") {
         "red16.png" => (16, 16),
         "blue8.png" => (8, 8),
-        "lines.mov" | "matte_black.png" | "matte_white.png" | "half.png" => (4, 4),
+        "lines.mov" | "matte_black.png" | "matte_white.png" | "half.png" | "scan.dpx" | "plate.dpx" => (4, 4),
         _ => (10, 10),
     }
 }
@@ -64,7 +70,12 @@ impl FootageSource for Synthetic {
         for y in 0..h {
             for x in 0..w {
                 // Decoders hand out premultiplied pixels (straight file colour × alpha).
-                let p = file_px(&f.path, x, y);
+                let mut p = file_px(&f.path, x, y);
+                // A log scan sequence: code 95 on even frames, 685 on odd ones.
+                if f.path.ends_with("frames.dpx") {
+                    let v = if f.frame_rate.frame_at(t) % 2 == 0 { 95.0 } else { 685.0 } / 1023.0;
+                    p = [v, v, v, 1.0];
+                }
                 img.set(x, y, [p[0] * p[3], p[1] * p[3], p[2] * p[3], p[3]]);
             }
         }
@@ -76,7 +87,7 @@ struct Probe;
 impl crate::Importer for Probe {
     fn probe(&self, path: &str) -> Result<Footage, String> {
         let (w, h) = size_of(path);
-        let video = path.ends_with(".mov");
+        let video = path.ends_with(".mov") || path.ends_with("frames.dpx");
         Ok(Footage {
             path: path.into(),
             kind: if video { FootageKind::Video } else { FootageKind::Still },
@@ -431,3 +442,125 @@ fn guess_alpha_invert_and_linear_light() {
     s.execute("file.applyInterpretation", json!({"items": [w.0]})).unwrap();
     assert!(foot(&s, w).preserve_rgb);
 }
+
+/// Color ▸ Cineon Settings: Logarithmic Conversion turns a DPX file's log code values into the
+/// Current Gamma between the converted points (off, they show as stored); the converted points
+/// are read and reported in the chosen Units; out-of-range values and footage that is not DPX
+/// or Cineon are refused; Remember / Apply Interpretation and undo carry the settings.
+#[test]
+fn cineon_settings_convert_dpx_code_values() {
+    let mut s = session();
+    let d = import(&mut s, "/m/scan.dpx");
+    let other = import(&mut s, "/m/plate.dpx");
+    let png = import(&mut s, "/m/red16.png");
+    let foot = |s: &Session, i: ItemId| match &s.project.item(i).unwrap().kind {
+        ItemKind::Footage(f) => f.clone(),
+        _ => panic!("not footage"),
+    };
+    s.execute("comp.new", json!({"name": "C", "width": 4, "height": 4, "frameRate": 10, "duration": 1})).unwrap();
+    let c = s.active_comp_id().unwrap();
+    s.execute("layer.addItem", json!({"item": d.0})).unwrap();
+    let at = |s: &Session, x: i64| px(s, c, 0.0, RenderOpts::default(), x, 0)[0];
+    let near = |a: f32, b: f32| (a - b).abs() < 1.5 / 255.0;
+    // Off: the code values as stored.
+    assert!(near(at(&s, 2), 400.0 / 1023.0), "{}", at(&s, 2));
+    // The checked path (control channel, MCP) accepts every Cineon parameter the doc lists.
+    let out = s.execute_checked("file.interpretFootage", json!({"items": [d.0], "logConversion": true, "highlightRolloff": 0})).unwrap();
+    assert_eq!(out["items"][0]["cineon"]["logConversion"], true, "{out}");
+    assert!(near(at(&s, 0), 0.0) && near(at(&s, 1), 1.0), "{} {}", at(&s, 0), at(&s, 1));
+    assert!(near(at(&s, 2), 0.26190), "code 400 at gamma 1.7: {}", at(&s, 2));
+    s.execute("file.interpretFootage", json!({"item": d.0, "currentGamma": 1})).unwrap();
+    assert!(near(at(&s, 2), 0.10251), "code 400 in linear light: {}", at(&s, 2));
+    // Converted points, in 8-bit units.
+    let out = s
+        .execute_checked("file.interpretFootage", json!({"items": [d.0], "cineonUnits": "8bit", "convertedBlack": 16, "convertedWhite": 235, "currentGamma": 1, "tenBitBlack": 95, "tenBitWhite": 685}))
+        .unwrap();
+    assert_eq!(out["items"][0]["cineon"]["units"], "8bit");
+    assert!((out["items"][0]["cineon"]["convertedWhite"].as_f64().unwrap() - 235.0).abs() < 1e-3, "{out}");
+    assert!(near(at(&s, 0), 16.0 / 255.0) && near(at(&s, 1), 235.0 / 255.0), "{} {}", at(&s, 0), at(&s, 1));
+    // The form sends the points in the units it showed them in (`pointUnits`) with a new Units.
+    s.execute_checked("file.interpretFootage", json!({"items": [d.0], "pointUnits": "8bit", "cineonUnits": "float", "convertedWhite": 255})).unwrap();
+    let f = foot(&s, d);
+    assert_eq!(f.cineon.units, effectcraft_project::CineonUnits::Float);
+    assert!((f.cineon.converted_white - 1023.0).abs() < 1e-3, "{:?}", f.cineon);
+    // Refused: a black point at or above the white point, values out of range, and footage
+    // that is not DPX or Cineon. Nothing changes.
+    let before = foot(&s, d).cineon;
+    for bad in [
+        json!({"item": d.0, "tenBitBlack": 700}),
+        json!({"item": d.0, "tenBitWhite": 2000}),
+        json!({"item": d.0, "currentGamma": 0}),
+        json!({"item": d.0, "highlightRolloff": -1}),
+        json!({"item": d.0, "convertedWhite": 1.5}),
+        json!({"item": d.0, "cineonUnits": "12bit"}),
+        json!({"item": png.0, "logConversion": true}),
+    ] {
+        assert!(s.execute("file.interpretFootage", bad.clone()).is_err(), "{bad}");
+    }
+    assert_eq!(foot(&s, d).cineon, before);
+    assert!(foot(&s, png).cineon == effectcraft_project::CineonSettings::default());
+    // With DPX and other footage selected, only the DPX file takes the settings.
+    s.execute("file.interpretFootage", json!({"items": [png.0, other.0], "logConversion": true})).unwrap();
+    assert!(foot(&s, other).cineon.log_conversion && !foot(&s, png).cineon.log_conversion);
+    s.execute("edit.undo", json!({})).unwrap();
+    assert!(!foot(&s, other).cineon.log_conversion);
+    // Remember / Apply Interpretation.
+    s.state.project_selection = vec![d];
+    s.execute("file.rememberInterpretation", json!({"item": d.0})).unwrap();
+    s.execute("file.applyInterpretation", json!({"items": [other.0, png.0]})).unwrap();
+    assert_eq!(foot(&s, other).cineon, before);
+    assert_eq!(foot(&s, png).cineon, effectcraft_project::CineonSettings::default());
+    // Off again: as stored.
+    s.execute("file.interpretFootage", json!({"item": d.0, "logConversion": false})).unwrap();
+    assert!(near(at(&s, 2), 400.0 / 1023.0), "{}", at(&s, 2));
+    // Frame Mix blends converted frames: halfway between code 95 (black) and 685 (white) at
+    // Current Gamma 1 is 0.5, not the conversion of the blended code values.
+    let seq = import(&mut s, "/m/frames.dpx");
+    s.execute("file.interpretFootage", json!({"item": seq.0, "logConversion": true, "currentGamma": 1, "highlightRolloff": 0})).unwrap();
+    s.execute("comp.new", json!({"name": "Blend", "width": 10, "height": 10, "frameRate": 20, "duration": 1})).unwrap();
+    let bc = s.active_comp_id().unwrap();
+    s.execute("layer.addItem", json!({"item": seq.0})).unwrap();
+    s.execute("layer.frameBlending", json!({"mode": "frameMix"})).unwrap();
+    let mid = px(&s, bc, 0.05, RenderOpts::default(), 5, 5)[0];
+    assert!(near(mid, 0.5), "frame-mixed log frames: {mid}");
+    // A DPX proxy of a composition: Interpret Proxy's settings convert it where it stands in.
+    s.execute("comp.new", json!({"name": "Inner", "width": 4, "height": 4, "frameRate": 10, "duration": 1})).unwrap();
+    let inner = s.active_comp_id().unwrap();
+    s.execute("comp.new", json!({"name": "Outer", "width": 4, "height": 4, "frameRate": 10, "duration": 1})).unwrap();
+    let outer = s.active_comp_id().unwrap();
+    s.execute("layer.addItem", json!({"item": inner.0})).unwrap();
+    s.execute("file.setProxy", json!({"item": inner.0, "path": "/m/scan.dpx"})).unwrap();
+    let proxied = |s: &Session, x: i64| px(s, outer, 0.0, RenderOpts::default(), x, 0)[0];
+    assert!(near(proxied(&s, 1), 685.0 / 1023.0), "{}", proxied(&s, 1));
+    s.execute_checked("file.interpretProxy", json!({"items": [inner.0], "logConversion": true, "highlightRolloff": 0})).unwrap();
+    assert!(near(proxied(&s, 0), 0.0) && near(proxied(&s, 1), 1.0), "{} {}", proxied(&s, 0), proxied(&s, 1));
+}
+
+/// The Footage panel, the Project panel thumbnail and the tracker's source frames show DPX
+/// footage with its Cineon Settings, as a composition renders it.
+#[test]
+fn cineon_settings_apply_to_footage_panel_thumbnail_and_tracking() {
+    let mut s = session();
+    let d = import(&mut s, "/m/scan.dpx");
+    s.execute("comp.new", json!({"name": "C", "width": 4, "height": 4, "frameRate": 10, "duration": 1})).unwrap();
+    let c = s.active_comp_id().unwrap();
+    s.execute("layer.addItem", json!({"item": d.0})).unwrap();
+    s.execute("file.interpretFootage", json!({"item": d.0, "logConversion": true, "highlightRolloff": 0})).unwrap();
+    let near = |a: f32, b: f32| (a - b).abs() < 1.5 / 255.0;
+    let rendered = px(&s, c, 0.0, RenderOpts::default(), 2, 0)[0];
+    assert!(near(rendered, 0.26190), "code 400 at gamma 1.7: {rendered}");
+    let f = match &s.project.item(d).unwrap().kind {
+        ItemKind::Footage(f) => f.clone(),
+        _ => panic!("not footage"),
+    };
+    let panel = crate::commands::footage_panel::frame(&s, d, &f, Tick::ZERO).unwrap().get(2, 0)[0];
+    assert!(near(panel, rendered), "Footage panel: {panel}");
+    let (w, _, rgba) = (s.thumbnail_job(d, Tick::ZERO, 64).unwrap())().unwrap();
+    assert_eq!(w, 4);
+    let thumb = rgba[8] as f32 / 255.0;
+    assert!(near(thumb, rendered), "Project panel thumbnail: {thumb}");
+    let comp = s.project.comp(c).unwrap();
+    let r = crate::render::Renderer::new(&s.project, s.footage.as_ref(), RenderOpts::default());
+    let (img, _) = crate::tracking::source_frame(&r, &s.project, c, comp, &comp.layers[0], Tick::ZERO, None).unwrap();
+    assert!(near(img.get(2, 0)[0], rendered), "tracker source frame: {}", img.get(2, 0)[0]);
+}

crates/engine/src/tests/rig3d.rs

@@ -7,7 +7,7 @@ use std::sync::Arc;
 use effectcraft_geom::{Vec3, vec3};
 use effectcraft_keyframe::Value as KV;
 use effectcraft_project::{Footage, FootageKind, GroupKind, ItemId, Layer, LayerId, LayerSource, LightKind, Project};
-use effectcraft_render::three_d::camera::layer_frame;
+use effectcraft_render::three_d::camera::{is_two_node, layer_frame};
 use effectcraft_render::{EvalCtx, FootageSource, RenderOpts};
 use effectcraft_time::{FrameRate, Tick};
 use serde_json::{Value, json};
@@ -40,7 +40,7 @@ fn close3(a: [f64; 3], b: [f64; 3], tol: f64) -> bool {
 fn frame(s: &Session, id: u64) -> (Vec3, Vec3) {
     let c = cid(s);
     let comp = s.project.comp(c).unwrap();
-    let ctx = EvalCtx { project: &s.project, comp_id: c, comp, time: Tick::ZERO, expr: None, footage: None };
+    let ctx = EvalCtx { project: &s.project, comp_id: c, comp, time: Tick::ZERO, expr: None, footage: None, property_overrides: &[], media_overrides: &[] };
     let (e, f, _) = layer_frame(&ctx, comp.layer(LayerId(id)).unwrap());
     (e, f)
 }
@@ -217,8 +217,189 @@ fn control_light_with_camera_follows_and_releases() {
     assert!(s.execute("light.controlWithCamera", json!({"layers": [cam]})).is_err());
 }
 
+/// Parenting keeps a camera where it is (After Effects' Parent & Link): Position and Point of
+/// Interest are re-expressed in the null's space, so the frame does not move.
+#[test]
+fn parented_camera_keeps_its_frame_under_an_offset_null() {
+    let mut s = session();
+    let cam = camera(&mut s);
+    let (eye0, f0) = frame(&s, cam);
+    let nul = s.execute("layer.newNull", json!({})).unwrap()["layer"].as_u64().unwrap();
+    s.execute("prop.set", json!({"layer": nul, "path": "transform/position", "value": [100, 60, 0]})).unwrap();
+    s.execute("layer.setParent", json!({"layers": [cam], "parent": nul})).unwrap();
+    let (eye1, f1) = frame(&s, cam);
+    assert!((eye1 - eye0).length() < 1e-6 && (f1 - f0).length() < 1e-6, "{eye0:?} {eye1:?}");
+    // The null's origin is Position minus its default anchor (50, 50): (50, 10) in the comp.
+    let c = layer_in(&s, cid(&s), cam);
+    assert!(close3(v3(&c, "transform/position"), [270.0, 170.0, -800.0], 1e-6), "{:?}", v3(&c, "transform/position"));
+    assert!(close3(v3(&c, "transform/poi"), [270.0, 170.0, 0.0], 1e-6), "{:?}", v3(&c, "transform/poi"));
+    // Moving the null carries the camera and keeps its aim.
+    s.execute("prop.set", json!({"layer": nul, "path": "transform/position", "value": [140, 90, 0]})).unwrap();
+    let (eye2, f2) = frame(&s, cam);
+    assert!((eye2 - (eye0 + vec3(40.0, 30.0, 0.0))).length() < 1e-6, "{eye2:?}");
+    assert!((f2 - f0).length() < 1e-6, "{f2:?}");
+}
+
+/// World (eye, forward, down) of a layer in the active comp at time `t`.
+fn frame_at(s: &Session, id: u64, t: Tick) -> (Vec3, Vec3, Vec3) {
+    let c = cid(s);
+    let comp = s.project.comp(c).unwrap();
+    let ctx = EvalCtx { project: &s.project, comp_id: c, comp, time: t, expr: None, footage: None, property_overrides: &[], media_overrides: &[] };
+    layer_frame(&ctx, comp.layer(LayerId(id)).unwrap())
+}
+
+/// Whether two frames agree on eye, forward and down.
+fn frames_match(a: (Vec3, Vec3, Vec3), b: (Vec3, Vec3, Vec3)) -> bool {
+    (a.0 - b.0).length() < 1e-6 && (a.1 - b.1).length() < 1e-6 && (a.2 - b.2).length() < 1e-6
+}
+
+/// A 3D null off-centre in the comp, with an Orientation and a Z rotation.
+fn rotated_null(s: &mut Session, orientation: [f64; 3], turn: f64) -> u64 {
+    let nul = s.execute("layer.newNull", json!({})).unwrap()["layer"].as_u64().unwrap();
+    s.execute("layer.setSwitch", json!({"layers": [nul], "switch": "threeD", "value": true})).unwrap();
+    s.execute("prop.set", json!({"layer": nul, "path": "transform/position", "value": [100, 60, 40]})).unwrap();
+    s.execute("prop.set", json!({"layer": nul, "path": "transform/orientation", "value": orientation})).unwrap();
+    s.execute("prop.set", json!({"layer": nul, "path": "transform/rotation", "value": turn})).unwrap();
+    nul
+}
+
+/// A two-node camera under a rotated null keeps its eye, aim and roll: its Orientation is
+/// re-expressed against the new aim, so Up does not drift.
+#[test]
+fn two_node_camera_under_rotated_null_keeps_its_roll() {
+    let mut s = session();
+    let cam = camera(&mut s);
+    s.execute("prop.set", json!({"layer": cam, "path": "transform/rotation", "value": 25})).unwrap();
+    assert!(is_two_node(&layer_in(&s, cid(&s), cam)));
+    let before = frame_at(&s, cam, Tick::ZERO);
+    let nul = rotated_null(&mut s, [20.0, -35.0, 60.0], 30.0);
+    s.execute("layer.setParent", json!({"layers": [cam], "parent": nul})).unwrap();
+    let after = frame_at(&s, cam, Tick::ZERO);
+    assert!(frames_match(before, after), "{before:?} {after:?}");
+}
+
+#[test]
+fn parented_point_light_keeps_its_direction_under_a_rotated_null() {
+    let mut s = session();
+    let light = s.execute("layer.newLight", json!({"kind": "Point", "position": [320, 180, -500]})).unwrap()["layer"].as_u64().unwrap();
+    s.execute("prop.set", json!({"layer": light, "path": "transform/orientation", "value": [30, 0, 0]})).unwrap();
+    let (eye0, f0) = frame(&s, light);
+    let nul = s.execute("layer.newNull", json!({})).unwrap()["layer"].as_u64().unwrap();
+    s.execute("prop.set", json!({"layer": nul, "path": "transform/position", "value": [100, 60, 0]})).unwrap();
+    s.execute("prop.set", json!({"layer": nul, "path": "transform/rotation", "value": 30})).unwrap();
+    s.execute("layer.setParent", json!({"layers": [light], "parent": nul})).unwrap();
+    let (eye1, f1) = frame(&s, light);
+    assert!((eye1 - eye0).length() < 1e-6 && (f1 - f0).length() < 1e-6, "{eye0:?} {eye1:?} {f0:?} {f1:?}");
+}
+
+/// Keyed Orientation under a Z-only turn is shifted exactly, so the light keeps its direction at
+/// every time, between the keys too.
+#[test]
+fn keyed_orientation_under_a_z_turn_keeps_the_direction_at_every_time() {
+    let mut s = session();
+    let light = s.execute("layer.newLight", json!({"kind": "Point", "position": [320, 180, -500]})).unwrap()["layer"].as_u64().unwrap();
+    for (time, value) in [(0.0, json!([-8.0, 12.0, -13.0])), (1.0, json!([5.0, 18.0, 14.0]))] {
+        s.execute("prop.addKey", json!({"layer": light, "path": "transform/orientation", "time": time, "value": value})).unwrap();
+    }
+    let times = [0.0, 0.25, 0.5, 0.75, 1.0].map(Tick::from_seconds_f64);
+    let before = times.map(|t| frame_at(&s, light, t));
+    let nul = rotated_null(&mut s, [0.0, 0.0, 0.0], 30.0);
+    s.execute("layer.setParent", json!({"layers": [light], "parent": nul})).unwrap();
+    for (t, b) in times.into_iter().zip(before) {
+        assert!(frames_match(b, frame_at(&s, light, t)), "a Z-only turn keeps the light's direction");
+    }
+}
+
+/// Under a tilted null the keys alone cannot follow (Euler angles are blended between them), so keys are
+/// added between them: the light keeps its direction within a small angle at every time.
+#[test]
+fn keyed_orientation_under_a_tilted_null_follows_between_the_keys() {
+    {
+        let mut s = session();
+        let light = s.execute("layer.newLight", json!({"kind": "Point", "position": [320, 180, -500]})).unwrap()["layer"].as_u64().unwrap();
+        for (time, value) in [(0.0, json!([-8.0, 12.0, -13.0])), (1.5, json!([50.0, 118.0, 74.0]))] {
+            s.execute("prop.addKey", json!({"layer": light, "path": "transform/orientation", "time": time, "value": value})).unwrap();
+        }
+        let times = [0.0, 0.2, 0.5, 0.9, 1.3, 1.5].map(Tick::from_seconds_f64);
+        let before = times.map(|t| frame_at(&s, light, t));
+        let nul = rotated_null(&mut s, [20.0, -35.0, 60.0], 30.0);
+        s.execute("layer.setParent", json!({"layers": [light], "parent": nul})).unwrap();
+        for (t, b) in times.into_iter().zip(before) {
+            let a = frame_at(&s, light, t);
+            // 0.05 degrees is about 9e-4 of a radian on a unit vector.
+            assert!((a.0 - b.0).length() < 1e-6 && (a.1 - b.1).length() < 2e-3, "at {t:?}: {:?} vs {:?}", a.1, b.1);
+        }
+        assert!(layer_in(&s, cid(&s), light).props.prop("transform/orientation").unwrap().keys.len() > 2, "keys were added between the two");
+    }
+}
+
+/// A one-node light parented under a mirrored null (Z scale -100%) keeps the Position and
+/// Orientation it was authored with: it has no Scale to carry the mirror, so none of it is
+/// compensated rather than reversing its frame (a half-compensated light would point backwards).
+#[test]
+fn one_node_light_under_a_mirrored_null_keeps_its_authored_values() {
+    let mut s = session();
+    let light = s.execute("layer.newLight", json!({"kind": "Point", "position": [320, 180, -500]})).unwrap()["layer"].as_u64().unwrap();
+    s.execute("prop.set", json!({"layer": light, "path": "transform/orientation", "value": [30, 0, 0]})).unwrap();
+    let before = layer_in(&s, cid(&s), light);
+    let nul = rotated_null(&mut s, [0.0, 0.0, 0.0], 0.0);
+    s.execute("prop.set", json!({"layer": nul, "path": "transform/scale", "value": [100, 100, -100]})).unwrap();
+    s.execute("layer.setParent", json!({"layers": [light], "parent": nul})).unwrap();
+    let after = layer_in(&s, cid(&s), light);
+    assert_eq!(after.parent, Some(LayerId(nul)));
+    assert_eq!(v3(&after, "transform/position"), v3(&before, "transform/position"));
+    assert_eq!(v3(&after, "transform/orientation"), v3(&before, "transform/orientation"));
+}
+
+/// The cap on keys added by baking is for the whole Orientation property, not for each segment:
+/// many strongly eased segments under a tilted parent stay within it.
+#[test]
+fn baked_orientation_keys_are_capped_across_the_whole_property() {
+    let mut s = session();
+    let light = s.execute("layer.newLight", json!({"kind": "Point", "position": [320, 180, -500]})).unwrap()["layer"].as_u64().unwrap();
+    let count = 120;
+    for i in 0..count {
+        let swing = if i % 2 == 0 { json!([0.0, 0.0, 0.0]) } else { json!([170.0, 60.0, 120.0]) };
+        s.execute("prop.addKey", json!({"layer": light, "path": "transform/orientation", "time": i as f64 * 0.05, "value": swing})).unwrap();
+    }
+    let uid = layer_in(&s, cid(&s), light).props.prop("transform/orientation").unwrap().uid;
+    let keys: Vec<_> = (0..count).map(|i| json!({"layer": light, "prop": uid, "time": i as f64 * 0.05})).collect();
+    s.execute("keys.select", json!({"keys": keys})).unwrap();
+    s.execute("keys.easyEase", json!({})).unwrap();
+    let nul = rotated_null(&mut s, [20.0, -35.0, 60.0], 30.0);
+    s.execute("layer.setParent", json!({"layers": [light], "parent": nul})).unwrap();
+    let n = layer_in(&s, cid(&s), light).props.prop("transform/orientation").unwrap().keys.len();
+    assert!(n <= 4096, "{n} keys: the cap is for the property, not per segment");
+    // the segments the cap left unchecked keep their authored easing instead of turning into straight blends
+    let orientation = layer_in(&s, cid(&s), light);
+    let keys = &orientation.props.prop("transform/orientation").unwrap().keys;
+    let last = keys.iter().rev().nth(1).expect("the penultimate key");
+    assert_ne!(last.out_interp, effectcraft_keyframe::Interp::Linear, "the last segment keeps its authored easing");
+}
+
 // ---------------------------------------------------------------- from 3D model
 
+/// Easy Ease agrees with a straight blend at the midpoint, but not at the quarter points.
+#[test]
+fn eased_orientation_under_x_parent_keeps_motion_between_keys() {
+    let mut s = session();
+    let light = s.execute("layer.newLight", json!({"kind": "Point", "position": [320, 180, -500]})).unwrap()["layer"].as_u64().unwrap();
+    for (time, value) in [(0.0, json!([0.0, 0.0, 0.0])), (1.0, json!([90.0, 0.0, 0.0]))] {
+        s.execute("prop.addKey", json!({"layer": light, "path": "transform/orientation", "time": time, "value": value})).unwrap();
+    }
+    let uid = layer_in(&s, cid(&s), light).props.prop("transform/orientation").unwrap().uid;
+    s.execute("keys.select", json!({"keys": [{"layer": light, "prop": uid, "time": 0.0}, {"layer": light, "prop": uid, "time": 1.0}]})).unwrap();
+    s.execute("keys.easyEase", json!({})).unwrap();
+    let times: Vec<_> = (0..=100).map(|i| Tick::from_seconds_f64(i as f64 / 100.0)).collect();
+    let before: Vec<_> = times.iter().map(|t| frame_at(&s, light, *t)).collect();
+    let parent = rotated_null(&mut s, [30.0, 0.0, 0.0], 0.0);
+    s.execute("layer.setParent", json!({"layers": [light], "parent": parent})).unwrap();
+    for (t, b) in times.into_iter().zip(before) {
+        let a = frame_at(&s, light, t);
+        assert!((a.0 - b.0).length() < 1e-6 && (a.1 - b.1).length() < 1e-3, "at {t:?}: {:?} vs {:?}", a.1, b.1);
+    }
+}
+
 struct DiskModels;
 
 impl FootageSource for DiskModels {

crates/engine/src/tests/sequence.rs

@@ -104,10 +104,11 @@ fn numbered_stills_import_as_stills_by_default() {
     let r = s.execute("file.import", json!({"paths": [dir.clone()], "drag": true})).unwrap();
     let (name, f) = footage(&s, &r["items"][0]);
     assert_eq!((name.as_str(), f.kind), ("shot_[0001-0005].png", FootageKind::Sequence));
-    // Scripts and agents naming one frame without `sequence` still get its run.
-    let r = s.execute("file.import", json!({"paths": [at(&dir, "shot_0003.png")]})).unwrap();
-    let (_, f) = footage(&s, &r["items"][0]);
-    assert_eq!(f.kind, FootageKind::Sequence);
+    // #2018: scripts and agents naming one frame without `sequence` get that still, as
+    // `ImportOptions.sequence` defaults to false in After Effects.
+    let r = s.execute("file.import", json!({"paths": [at(&dir, "shot_0005.png")]})).unwrap();
+    let (name, f) = footage(&s, &r["items"][0]);
+    assert_eq!((name.as_str(), f.kind), ("shot_0005.png", FootageKind::Still));
 }
 
 #[test]
@@ -181,14 +182,58 @@ fn interpret_footage_start_timecode_relabels_source_time() {
 }
 
 #[test]
-fn replace_footage_and_reload_keep_sequences() {
+fn replace_footage_keeps_a_still_a_still() {
     let dir = folder(&RUN);
     let mut s = session();
     let item = s.execute("file.import", json!({"paths": [at(&dir, "shot_0001.png")], "sequence": false})).unwrap()["items"][0].clone();
     s.state.project_selection = vec![ItemId(item.as_u64().unwrap())];
+    // Replacing with a numbered still does not silently turn the item into a sequence (#2073).
     s.execute("file.replaceFootage", json!({"path": at(&dir, "shot_0004.png")})).unwrap();
     let (name, f) = footage(&s, &item);
-    assert_eq!((name.as_str(), f.sequence.len()), ("shot_[0001-0005].png", 4));
+    assert_eq!((name.as_str(), f.kind), ("shot_0004.png", FootageKind::Still));
+    // JSON null is unspecified, not "on": the still stays a still.
+    s.execute("file.replaceFootage", json!({"path": at(&dir, "shot_0004.png"), "sequence": null})).unwrap();
+    let (name, f) = footage(&s, &item);
+    assert_eq!((name.as_str(), f.kind), ("shot_0004.png", FootageKind::Still));
+    // Alphabetical is a sequence modifier, not a request to make one.
+    s.execute("file.replaceFootage", json!({"path": at(&dir, "shot_0004.png"), "alphabetical": true})).unwrap();
+    let (name, f) = footage(&s, &item);
+    assert_eq!((name.as_str(), f.kind), ("shot_0004.png", FootageKind::Still));
+    // Asking for the run still brings it.
+    s.execute("file.replaceFootage", json!({"path": at(&dir, "shot_0004.png"), "sequence": true})).unwrap();
+    let (name, f) = footage(&s, &item);
+    assert_eq!((name.as_str(), f.kind, f.sequence.len()), ("shot_[0001-0005].png", FootageKind::Sequence, 4));
+}
+
+#[test]
+fn replace_footage_keeps_a_one_frame_run_a_sequence() {
+    let dir = folder(&["shot_0001.png", "shot_0002.png", "solo_0007.png", "cover.png"]);
+    let mut s = session();
+    let item = s.execute("file.import", json!({"paths": [at(&dir, "shot_0001.png")], "sequence": true})).unwrap()["items"][0].clone();
+    s.state.project_selection = vec![ItemId(item.as_u64().unwrap())];
+    // A numbered file with no other frame in its run is still the replacement for a sequence.
+    s.execute("file.replaceFootage", json!({"path": at(&dir, "solo_0007.png")})).unwrap();
+    let (name, f) = footage(&s, &item);
+    assert_eq!((name.as_str(), f.kind, f.sequence.len()), ("solo_0007.png", FootageKind::Sequence, 1));
+    // A single-file source keeps the sequence kind too.
+    s.execute("file.replaceFootage", json!({"path": at(&dir, "cover.png")})).unwrap();
+    let (name, f) = footage(&s, &item);
+    assert_eq!((name.as_str(), f.kind, f.sequence.len()), ("cover.png", FootageKind::Sequence, 1));
+    // An explicit `sequence: false` still asks for one frame.
+    s.execute("file.replaceFootage", json!({"path": at(&dir, "cover.png"), "sequence": false})).unwrap();
+    let (_, f) = footage(&s, &item);
+    assert_eq!((f.kind, f.sequence.len()), (FootageKind::Still, 0));
+}
+
+#[test]
+fn replace_footage_and_reload_keep_sequences() {
+    let dir = folder(&RUN);
+    let mut s = session();
+    let item = s.execute("file.import", json!({"paths": [at(&dir, "shot_0001.png")], "sequence": true})).unwrap()["items"][0].clone();
+    s.state.project_selection = vec![ItemId(item.as_u64().unwrap())];
+    s.execute("file.replaceFootage", json!({"path": at(&dir, "shot_0004.png")})).unwrap();
+    let (name, f) = footage(&s, &item);
+    assert_eq!((name.as_str(), f.kind, f.sequence.len()), ("shot_[0001-0005].png", FootageKind::Sequence, 4));
     // Reload finds a new frame and keeps the interpretation.
     s.execute("file.interpretFootage", json!({"items": [item], "frameRate": 12, "startTimecode": 2})).unwrap();
     std::fs::write(at(&dir, "shot_0003.png"), b"").unwrap();

crates/engine/src/tests/session.rs

@@ -86,7 +86,7 @@ fn imported_files_go_into_the_comp_where_they_were_dropped() {
     s.execute("file.import", params).unwrap();
     let comp = s.active_comp().unwrap();
     assert_eq!(comp.layers.iter().map(|l| l.name.as_str()).collect::<Vec<_>>(), ["a.png", "b.png", "Bg"]);
-    for l in &comp.layers[..2] {
+    for l in comp.layers.iter().take(2) {
         assert_eq!(l.props.prop("transform/position").map(|p| p.value.clone()), Some(effectcraft_keyframe::Value::Vec3([40.0, 50.0, 0.0])));
         assert_eq!(l.in_point, effectcraft_time::Tick::from_seconds_f64(1.0));
     }
@@ -159,6 +159,46 @@ fn background_imports_report_progress_and_select_what_arrived() {
     assert_eq!(r["items"].as_array().map(Vec::len), Some(1));
 }
 
+/// #2573: New Composition From Footage (`file.import {newComp}`) makes one composition of what
+/// the import made, first file on top, at once or when the background job lands; an import that
+/// made nothing makes no comp.
+#[test]
+fn new_comp_from_footage_makes_a_comp_of_what_was_imported() {
+    use effectcraft_project::{Footage, FootageKind, ItemKind};
+    struct Probe;
+    impl crate::Importer for Probe {
+        fn probe(&self, path: &str) -> Result<Footage, String> {
+            if path.ends_with(".xyz") {
+                return Err("unsupported file".into());
+            }
+            Ok(Footage { path: path.into(), kind: FootageKind::Still, width: 64, height: 32, has_video: true, ..Default::default() })
+        }
+    }
+    let mut s = Session { importer: Some(std::sync::Arc::new(Probe)), ..Default::default() };
+    let comps = |s: &Session| s.project.items.values().filter(|i| matches!(i.kind, ItemKind::Comp(_))).count();
+    let layers = |s: &Session| s.active_comp().unwrap().layers.iter().map(|l| l.name.clone()).collect::<Vec<_>>();
+    // At once.
+    s.execute("file.import", json!({"paths": ["/drop/a.png", "/drop/b.xyz"], "newComp": true})).unwrap();
+    assert_eq!(comps(&s), 1);
+    assert_eq!(layers(&s), ["a.png"]);
+    assert_eq!((s.active_comp().unwrap().width, s.active_comp().unwrap().height), (64, 32));
+    // In the background: the job's own items, whatever is selected or active meanwhile; it takes
+    // precedence over `addToComp`.
+    s.execute("file.import", json!({"paths": ["/drop/c.png", "/drop/d.png"], "background": true, "newComp": true, "addToComp": true})).unwrap();
+    s.state.project_selection.clear();
+    s.execute("jobs.wait", json!({})).unwrap();
+    assert_eq!(comps(&s), 2);
+    assert_eq!(layers(&s), ["c.png", "d.png"]);
+    // Nothing imported: no comp, and the failure is reported.
+    s.execute("file.import", json!({"paths": ["/drop/e.xyz"], "background": true, "newComp": true})).unwrap();
+    s.execute("jobs.wait", json!({})).unwrap();
+    assert_eq!(comps(&s), 2);
+    assert!(s.job_log.last().unwrap().message.contains("unsupported file"));
+    let r = s.execute("file.import", json!({"paths": ["/drop/f.xyz"], "newComp": true})).unwrap();
+    assert_eq!(comps(&s), 2);
+    assert_eq!(r["errors"].as_array().map(Vec::len), Some(1));
+}
+
 /// Audio, Lock and Shy don't change pixels: toggling them keeps the cached layers (#103).
 #[test]
 fn audio_lock_and_shy_keep_cached_layers() {
@@ -476,6 +516,9 @@ fn set_text_paragraph_fill_and_leading() {
     s.execute("layer.setText", json!({"layer": t, "hScale": 120, "vScale": 80, "baselineShift": 4, "smallCaps": true, "strokeOverFill": true})).unwrap();
     let d = doc(&s);
     assert_eq!((d.h_scale, d.v_scale, d.baseline_shift, d.small_caps, d.stroke_over_fill), (120.0, 80.0, 4.0, true, true));
+    s.execute("layer.setText", json!({"layer": t, "lineJoin": "bevel"})).unwrap();
+    assert_eq!(doc(&s).line_join, effectcraft_keyframe::LineJoin::Bevel);
+    assert!(s.execute("layer.setText", json!({"layer": t, "lineJoin": "square"})).is_err());
 }
 
 #[test]

crates/engine/src/tests/settings.rs

@@ -389,6 +389,23 @@ fn new_project_template_and_default_renderer() {
     let _ = std::fs::remove_dir_all(d);
 }
 
+#[test]
+fn project_files_are_indented_unless_compact_is_on() {
+    let d = tmp("compact-project-files");
+    let path = d.join("p.ecproj");
+    let mut s = session_with_comp();
+    s.execute("file.saveAs", json!({"path": path.to_string_lossy()})).unwrap();
+    let pretty = std::fs::read_to_string(&path).unwrap();
+    assert!(pretty.starts_with("{\n  \"savedBy\""), "indented by default");
+    s.execute("prefs.set", json!({"key": "project.compactProjectFiles", "value": true})).unwrap();
+    s.execute("file.saveAs", json!({"path": path.to_string_lossy()})).unwrap();
+    let compact = std::fs::read_to_string(&path).unwrap();
+    assert!(!compact.contains('\n'), "one line when Save Compact Project Files is on");
+    let open = |text: &str| effectcraft_project::Project::from_json(text).unwrap();
+    assert_eq!(open(&compact), open(&pretty), "both read back as the same project");
+    let _ = std::fs::remove_dir_all(d);
+}
+
 // ---------------------------------------------------------------- shortcuts
 
 #[test]
@@ -1072,6 +1089,14 @@ fn interface_language_is_validated_persisted_and_backward_compatible() {
     cs.load_settings();
     assert_eq!(cs.prefs.general.language, "cs");
     assert_eq!(Prefs::from_json(r#"{"general":{"language":"cs"}}"#).general.language, "cs");
+    // Polish, likewise.
+    assert!(crate::prefs::LANGUAGES.contains(&("Polski", "pl")));
+    s.execute("prefs.set", json!({"key": "general.language", "value": "pl"})).unwrap();
+    assert_eq!(s.execute("prefs.get", json!({"key": "general.language"})).unwrap(), json!("pl"));
+    let mut pl = Session { config: Some(store.clone()), ..Default::default() };
+    pl.load_settings();
+    assert_eq!(pl.prefs.general.language, "pl");
+    assert_eq!(Prefs::from_json(r#"{"general":{"language":"pl"}}"#).general.language, "pl");
     // Georgian too.
     assert!(crate::prefs::LANGUAGES.contains(&("ქართული", "ka")));
     s.execute("prefs.set", json!({"key": "general.language", "value": "ka"})).unwrap();

crates/engine/src/tests/shared_layers.rs

@@ -0,0 +1,42 @@
+//! An edit copies only the layer it changes: the others stay shared with the undo state, so an
+//! edit's cost doesn't grow with the size of the comp (scripts setting many keys went quadratic).
+
+use std::sync::Arc;
+
+use serde_json::json;
+
+use crate::Session;
+
+#[test]
+fn a_key_on_one_layer_leaves_the_other_layers_shared_with_undo() {
+    let mut s = Session::default();
+    s.execute("comp.new", json!({"name": "Big", "duration": 10, "frameRate": 30})).unwrap();
+    let ids: Vec<u64> = (0..20).map(|i| s.execute("layer.newNull", json!({"name": format!("N{i}")})).unwrap()["layer"].as_u64().unwrap()).collect();
+    let cid = s.active_comp_id().unwrap();
+    let before = s.project.clone();
+    s.execute("prop.addKey", json!({"layer": ids[7], "path": "transform/position", "time": 1.0, "value": [5, 5]})).unwrap();
+    let (old, new) = (before.comp(cid).unwrap(), s.project.comp(cid).unwrap());
+    assert_eq!(old.layers.len(), new.layers.len());
+    let edited = new.layers.iter().position(|l| l.id.0 == ids[7]).unwrap();
+    for i in 0..new.layers.len() {
+        assert_eq!(new.layers.same_at(&old.layers, i), i != edited, "layer {i} shared: {}", new.layers.same_at(&old.layers, i));
+    }
+    // Undo brings back the very same state, and the edited layer is the only one that differed.
+    s.execute("edit.undo", json!({})).unwrap();
+    assert!(Arc::ptr_eq(&s.project, &before));
+}
+
+#[test]
+fn layers_save_and_load_as_a_plain_list() {
+    let mut s = Session::default();
+    s.execute("comp.new", json!({"name": "Round trip", "duration": 5, "frameRate": 25})).unwrap();
+    for i in 0..3 {
+        s.execute("layer.newNull", json!({"name": format!("N{i}")})).unwrap();
+    }
+    let cid = s.active_comp_id().unwrap();
+    let comp = s.project.comp(cid).unwrap();
+    let text = serde_json::to_value(&comp.layers).unwrap();
+    assert_eq!(text.as_array().map(Vec::len), Some(3), "a JSON array of layers, as before");
+    let back: effectcraft_project::Layers = serde_json::from_value(text).unwrap();
+    assert_eq!(&back, &comp.layers);
+}

crates/engine/src/tests/shortcut_cmds.rs

@@ -184,6 +184,28 @@ fn in_and_out_points_stretch_to_the_current_time() {
     assert!(s.execute("layer.timeStretch", json!({"to": "middle"})).is_err());
 }
 
+#[test]
+fn trimming_out_to_the_playhead_keeps_its_frame_visible() {
+    let (mut s, ids) = session([(1.0, 9.0); 3]);
+    let frame = 1.0 / 30.0;
+    // Alt+] at 4 s: the Out edge lands one frame after the playhead, so 4 s is the layer's last
+    // visible frame — it must not be cut away at the playhead (as in After Effects).
+    s.execute("time.set", json!({"time": 4.0})).unwrap();
+    s.execute("layer.timing", json!({"layers": [ids[0]], "op": "trimOutToTime"})).unwrap();
+    assert!((span(&s, ids[0]).1 - (4.0 + frame)).abs() < 1e-9, "{:?}", span(&s, ids[0]));
+    // Alt+[ at 2 s: the playhead's frame becomes the layer's first visible one.
+    s.execute("time.set", json!({"time": 2.0})).unwrap();
+    s.execute("layer.timing", json!({"layers": [ids[1]], "op": "trimInToTime"})).unwrap();
+    assert!((span(&s, ids[1]).0 - 2.0).abs() < 1e-9, "{:?}", span(&s, ids[1]));
+    // Trimmed before the In point, the Out point keeps one frame of layer.
+    s.execute("time.set", json!({"time": 0.5})).unwrap();
+    s.execute("layer.timing", json!({"layers": [ids[2]], "op": "trimOutToTime"})).unwrap();
+    assert!((span(&s, ids[2]).1 - (1.0 + frame)).abs() < 1e-9, "{:?}", span(&s, ids[2]));
+    // One undo step back to the original span.
+    assert!(s.undo());
+    assert!((span(&s, ids[2]).1 - 9.0).abs() < 1e-9);
+}
+
 #[test]
 fn masks_are_stepped_through_and_wrap() {
     let (mut s, ids) = session([(0.0, 10.0); 3]);

crates/engine/src/tests/stubs.rs

@@ -584,3 +584,22 @@ fn convert_to_bezier_reads_the_shape_as_it_is_set() {
     let mid = |v: &[f64]| (v.iter().copied().fold(f64::MAX, f64::min) + v.iter().copied().fold(f64::MIN, f64::max)) / 2.0;
     assert!((mid(&xs) - 10.0).abs() < 1e-6 && (mid(&ys) - 5.0).abs() < 1e-6, "centred on the position: {:?} {:?}", mid(&xs), mid(&ys));
 }
+
+/// #2201: a viewer drag on the free-transform box sends one `path.freeTransform` per frame with a
+/// shared merge key; one undo must revert the whole drag, not the last frame.
+#[test]
+fn free_transform_drag_undoes_in_one_step() {
+    let mut s = comp();
+    let (l, m) = masked(&mut s);
+    s.state.selected_vertices.clear();
+    let before = mask_path(&s, l, m);
+    for k in [90, 90, 90, 90] {
+        s.execute("path.freeTransform", json!({"layer": l, "scale": k, "merge": "viewer-drag-1"})).unwrap();
+    }
+    let after = mask_path(&s, l, m);
+    assert_ne!(after, before);
+    s.execute("edit.undo", json!({})).unwrap();
+    assert_eq!(mask_path(&s, l, m), before, "one undo reverts the whole drag");
+    s.execute("edit.redo", json!({})).unwrap();
+    assert_eq!(mask_path(&s, l, m), after, "redo restores the whole drag");
+}

crates/engine/src/tests/tail.rs

@@ -421,6 +421,70 @@ fn camera_focus_commands_undo_and_serde() {
     assert!(s.execute("camera.linkFocusToPoi", json!({})).is_ok());
 }
 
+/// Set Focus Distance to Layer: degenerate targets (behind the camera, exactly at it) are clean
+/// errors, and a depth-of-field frame renders right after the command.
+#[test]
+fn camera_set_focus_to_layer_degenerate_targets_and_dof_frame() {
+    let mut s = comp(400, 300);
+    let t = s.execute("layer.newSolid", json!({"color": "#ffffff", "width": 50, "height": 50})).unwrap()["layer"].as_u64().unwrap();
+    s.execute("layer.setSwitch", json!({"layers": [t], "switch": "threeD", "value": true})).unwrap();
+    let cam = s.execute("layer.newCamera", json!({})).unwrap()["layer"].as_u64().unwrap();
+    s.execute("prop.set", json!({"layer": cam, "path": "transform/position", "value": [200, 150, -500]})).unwrap();
+    s.execute("prop.set", json!({"layer": cam, "path": "cameraOptions/dof", "value": true})).unwrap();
+    s.execute("layer.select", json!({"layers": [cam, t]})).unwrap();
+    // Behind the camera (which now sits at z = −500 looking towards +z).
+    s.execute("layer.setTransform", json!({"layer": t, "prop": "position", "value": [200, 150, -1000]})).unwrap();
+    let e = s.execute("camera.setFocusToLayer", json!({})).unwrap_err().to_string();
+    assert!(e.contains("behind the camera"), "{e}");
+    // Exactly at the camera: depth 0, still a clean error.
+    s.execute("layer.setTransform", json!({"layer": t, "prop": "position", "value": [200, 150, -500]})).unwrap();
+    assert!(s.execute("camera.setFocusToLayer", json!({})).is_err());
+    // In front: the command works, and the depth-of-field frame renders with finite pixels.
+    s.execute("layer.setTransform", json!({"layer": t, "prop": "position", "value": [200, 150, 400]})).unwrap();
+    let d = s.execute("camera.setFocusToLayer", json!({})).unwrap()["focusDistance"].as_f64().unwrap();
+    assert!((d - 900.0).abs() < 1e-6, "{d}");
+    // An out-of-focus 3D layer, which must visibly blur, and a 0%-scaled one, whose pixels cover
+    // ~0 screen pixels and so turn an ordinary defocus into a radius of ~1e9 buffer pixels.
+    s.execute("prop.set", json!({"layer": cam, "path": "cameraOptions/aperture", "value": 120})).unwrap();
+    let blur = s.execute("layer.newSolid", json!({"color": "#00ff00", "width": 60, "height": 60})).unwrap()["layer"].as_u64().unwrap();
+    s.execute("layer.setSwitch", json!({"layers": [blur], "switch": "threeD", "value": true})).unwrap();
+    s.execute("layer.setTransform", json!({"layer": blur, "prop": "position", "value": [200, 150, 1200]})).unwrap();
+    let invis = s.execute("layer.newSolid", json!({"color": "#ff0000", "width": 40, "height": 40})).unwrap()["layer"].as_u64().unwrap();
+    s.execute("layer.setSwitch", json!({"layers": [invis], "switch": "threeD", "value": true})).unwrap();
+    s.execute("layer.setTransform", json!({"layer": invis, "prop": "position", "value": [200, 150, 1600]})).unwrap();
+    s.execute("layer.setTransform", json!({"layer": invis, "prop": "scale", "value": [0.0, 0.0, 0.0]})).unwrap();
+    let cid = s.active_comp_id().unwrap();
+    let img = s.render(cid, effectcraft_time::Tick::ZERO, Default::default());
+    assert!(img.data.iter().all(|p| p.iter().all(|c| c.is_finite())), "non-finite pixels after setFocusToLayer");
+    // The DoF frame actually blurred (not a no-op blur): the same frame with DoF off differs.
+    s.execute("prop.set", json!({"layer": cam, "path": "cameraOptions/dof", "value": false})).unwrap();
+    let plain = s.render(cid, effectcraft_time::Tick::ZERO, Default::default());
+    assert_ne!(img.data, plain.data, "the out-of-focus layer should have blurred");
+}
+
+/// Set Focus Distance to Layer fails cleanly on a depth that isn't finite. Every stored number
+/// here is finite, but their difference overflows f64 to infinity; JSON has no infinity, so
+/// storing it would leave a project that can't be saved.
+#[test]
+fn camera_set_focus_to_layer_rejects_non_finite_depth() {
+    let mut s = comp(400, 300);
+    let t = s.execute("layer.newSolid", json!({"color": "#ffffff", "width": 50, "height": 50})).unwrap()["layer"].as_u64().unwrap();
+    s.execute("layer.setSwitch", json!({"layers": [t], "switch": "threeD", "value": true})).unwrap();
+    s.execute("layer.setTransform", json!({"layer": t, "prop": "position", "value": [200.0, 150.0, 1e308]})).unwrap();
+    let cam = s.execute("layer.newCamera", json!({})).unwrap()["layer"].as_u64().unwrap();
+    s.execute("layer.setTransform", json!({"layer": cam, "prop": "position", "value": [200.0, 150.0, -1e308]})).unwrap();
+    s.execute("layer.select", json!({"layers": [cam, t]})).unwrap();
+    let before = s.execute("prop.get", json!({"layer": cam, "path": "cameraOptions/focusDistance"})).unwrap()["value"].as_f64().unwrap();
+    let e = s.execute("camera.setFocusToLayer", json!({})).unwrap_err().to_string();
+    assert!(e.contains("out of range"), "{e}");
+    let after = s.execute("prop.get", json!({"layer": cam, "path": "cameraOptions/focusDistance"})).unwrap()["value"].as_f64().unwrap();
+    assert!((after - before).abs() < 1e-9, "a non-finite focus distance was written: {after}");
+    // The project still round-trips through serde (a stored infinity would come back as null).
+    let back = roundtrip(&s);
+    let f = back.comp(s.active_comp_id().unwrap()).unwrap().layer(LayerId(cam)).unwrap().props.prop("cameraOptions/focusDistance").unwrap().value.as_f64();
+    assert!((f - before).abs() < 1e-9, "serde focus distance: {f}");
+}
+
 /// An id sent as a string (`"98"`, as MCP clients often do) resolves as an id when no name matches.
 #[test]
 fn numeric_string_resolves_as_id() {

crates/engine/src/tests/text_edit.rs

@@ -199,6 +199,20 @@ fn typing_deleting_and_caret_movement() {
     assert!(s.state.text_edit.is_none());
 }
 
+/// Duplicating during a text edit moves the selection to the copy: the edit on the original ends
+/// (#2226), as in After Effects — typing must not keep editing an unselected layer.
+#[test]
+fn duplicate_during_a_text_edit_ends_the_edit() {
+    let (mut s, t) = session("Hello");
+    s.execute("text.edit", json!({"layer": t, "caret": 5})).unwrap();
+    let copy = s.execute("edit.duplicate", json!({"layers": [t]})).unwrap()[0].as_u64().unwrap();
+    assert_ne!(copy, t, "the duplicate is created");
+    assert_eq!(s.state.selected_layers, vec![effectcraft_project::LayerId(copy)], "the copy is selected");
+    assert!(s.state.text_edit.is_none(), "the edit ended with the selection move (#2226)");
+    assert_eq!(doc(&s, t).text, "Hello", "the original keeps its text");
+    assert_eq!(doc(&s, copy).text, "Hello", "and the copy carries it");
+}
+
 #[test]
 fn caret_style_applies_to_the_next_typed_text() {
     let (mut s, t) = session("ab");
@@ -260,25 +274,25 @@ fn clipboard_and_paste_formatting() {
 }
 
 #[test]
-fn type_tool_layers_point_box_and_empty_cleanup() {
+fn type_tool_layers_point_box_and_empty_layer_is_kept() {
     let mut s = Session::default();
     s.execute("comp.new", json!({"name": "C", "width": 640, "height": 360, "duration": 4})).unwrap();
     let t = s.execute("layer.newText", json!({"text": "", "position": [100, 200], "justify": "left", "edit": true})).unwrap()["layer"].as_u64().unwrap();
     assert_eq!(s.state.text_edit.as_ref().map(|e| e.layer.0), Some(t));
-    // Leaving an untouched Type-tool layer deletes it.
+    // Leaving an untouched Type-tool layer keeps it, as After Effects does.
     s.execute("text.endEdit", json!({})).unwrap();
-    assert!(s.active_comp().unwrap().layers.is_empty());
+    assert_eq!(s.active_comp().unwrap().layers.len(), 1, "an empty Type-tool layer is kept, as in AE");
     let b = s.execute("layer.newText", json!({"text": "", "box": [40, 50, 300, 120], "edit": true})).unwrap()["layer"].as_u64().unwrap();
     s.execute("text.insert", json!({"text": "Boxed"})).unwrap();
     let d = doc(&s, b);
     assert_eq!(d.box_size, Some([300.0, 120.0]));
     assert_eq!(d.box_pos, [-150.0, -60.0]);
-    let l = s.active_comp().unwrap().layers[0].clone();
+    let l = s.active_comp().unwrap().layers.iter().find(|l| l.id.0 == b).expect("the boxed layer").clone();
     assert_eq!(l.name, "Boxed", "named after its text");
     let pos = l.props.prop("transform/position").unwrap().value.as_vec3();
     assert_eq!([pos[0], pos[1]], [190.0, 110.0]);
     s.execute("text.endEdit", json!({})).unwrap();
-    assert_eq!(s.active_comp().unwrap().layers.len(), 1);
+    assert_eq!(s.active_comp().unwrap().layers.len(), 2, "both text layers stay, the empty one included");
     // Resizing the box (layer space) is an attribute too.
     s.execute("layer.setText", json!({"layer": b, "box": [-100, -60, 200, 120]})).unwrap();
     assert_eq!(doc(&s, b).box_size, Some([200.0, 120.0]));
@@ -928,11 +942,19 @@ fn fonts_lists_bundled_and_installed_families() {
     let r = s.execute("text.fonts", json!({"query": "noto ser", "rescan": true})).unwrap();
     assert_eq!(r["families"][0]["family"], "Noto Serif");
     // The bundled face is Regular; the OS can also provide Bold, Italic, or other faces.
-    // Compare against the independent directory inventory rather than assuming an empty OS.
-    let mut expected_styles = std::collections::BTreeSet::from(["Regular".to_string()]);
-    expected_styles.extend(installed.iter().filter(|face| face.family.eq_ignore_ascii_case("Noto Serif")).map(|face| face.style.clone()));
+    // Model `add_source()` on the independent directory inventory: a system face whose family
+    // and primary style duplicate an earlier face is skipped, with its named instances.
+    let mut expected_styles = std::collections::BTreeSet::from(["regular".to_string()]);
+    let mut retained = std::collections::BTreeSet::from([("noto serif".to_string(), "regular".to_string())]);
+    for face in installed.iter().filter(|face| face.family.eq_ignore_ascii_case("Noto Serif")) {
+        if retained.insert((face.family.to_ascii_lowercase(), face.style.to_ascii_lowercase())) {
+            expected_styles.insert(face.style.to_ascii_lowercase());
+            expected_styles.extend(face.instances.iter().map(|i| i.style.to_ascii_lowercase()));
+        }
+    }
     let styles: Vec<String> = r["families"][0]["styles"].as_array().unwrap().iter().map(|style| style.as_str().unwrap().to_string()).collect();
-    assert_eq!(styles.iter().cloned().collect::<std::collections::BTreeSet<_>>(), expected_styles);
+    // `families()` keeps the first spelling of a style that differs only in case.
+    assert_eq!(styles.iter().map(|style| style.to_ascii_lowercase()).collect::<std::collections::BTreeSet<_>>(), expected_styles);
     assert_eq!(styles.len(), expected_styles.len(), "style menu has no duplicates");
     assert!(r["families"].as_array().unwrap().iter().all(|f| f["family"].as_str().unwrap().to_lowercase().contains("noto ser")));
     // The style menus offer a family's own styles.
@@ -1202,7 +1224,7 @@ fn deselect_all_ends_the_open_edit() {
 }
 
 #[test]
-fn deselect_all_discards_an_empty_type_tool_layer() {
+fn deselect_all_keeps_an_empty_type_tool_layer() {
     let (mut s, _keep) = session("Hello");
     let new = s.execute("layer.newText", json!({"text": "", "position": [80.0, 80.0], "edit": true})).unwrap()["layer"].as_u64().unwrap();
     assert!(
@@ -1214,7 +1236,5 @@ fn deselect_all_discards_an_empty_type_tool_layer() {
     s.execute("edit.deselectAll", json!({})).unwrap();
     assert!(s.state.text_edit.is_none());
     assert!(s.state.selected_layers.is_empty());
-    assert_eq!(count(&s), before - 1, "a Type-tool layer left empty is removed, as text.endEdit does");
-    s.execute("edit.undo", json!({})).unwrap();
-    assert_eq!(count(&s), before, "that removal is one undo step of its own, as on text.endEdit");
+    assert_eq!(count(&s), before, "an empty Type-tool layer is kept, as in After Effects");
 }

crates/engine/src/tests/three_d.rs

@@ -1,6 +1,6 @@
 //! 3D commands: cameras, lights, views, camera tools (with undo/redo), and the 3D demo comp.
 
-use effectcraft_project::{AutoOrient, LayerSource, LightKind};
+use effectcraft_project::{AutoOrient, LayerSource, LightKind, Renderer};
 use effectcraft_render::three_d::View3D;
 use serde_json::json;
 
@@ -148,6 +148,85 @@ fn deleting_a_source_layer_clears_the_reference() {
     assert!(s.active_comp().unwrap().layer(effectcraft_project::LayerId(sky)).is_some());
 }
 
+/// #2436: only the Advanced 3D renderer lights with Environment lights, and new comps are
+/// Classic 3D, so one had no visible effect. Adding one (or changing a light into one) switches
+/// the comp to Advanced 3D (in the same undo step, with a toast), as After Effects does.
+#[test]
+fn environment_lights_switch_classic_comps_to_advanced_3d() {
+    let toasts = |s: &mut Session| -> Vec<String> {
+        s.drain_events().into_iter().filter_map(|e| if let crate::Event::Toast { message, .. } = e { Some(message) } else { None }).collect()
+    };
+    let mut s = session();
+    let text = s.execute("layer.newText", json!({"text": "Hi"})).unwrap()["layer"].as_u64().unwrap();
+    assert_eq!(s.active_comp().unwrap().renderer, Renderer::Classic3D);
+    toasts(&mut s);
+    let r = s.execute("layer.newLight", json!({"kind": "Environment"})).unwrap();
+    assert_eq!(r["advanced3d"], true);
+    assert_eq!(s.active_comp().unwrap().renderer, Renderer::Advanced3D);
+    // As with Composition Settings: the text layer gets Geometry Options.
+    assert!(s.active_comp().unwrap().layer(effectcraft_project::LayerId(text)).unwrap().props.sub("geometryOptions").is_some());
+    assert!(toasts(&mut s).iter().any(|m| m.contains("Advanced 3D")));
+    // A second Environment light leaves the comp (and the user) alone.
+    s.execute("layer.newLight", json!({"kind": "Environment"})).unwrap();
+    assert!(toasts(&mut s).is_empty());
+    // Undoing the creations takes the lights and the switch back together.
+    s.undo();
+    s.undo();
+    assert_eq!(s.active_comp().unwrap().renderer, Renderer::Classic3D);
+    assert_eq!(layer_count(&s), 1);
+    // Changing a light to Environment switches too, and undoes with the type.
+    let spot = s.execute("layer.newLight", json!({"kind": "Spot"})).unwrap()["layer"].as_u64().unwrap();
+    assert_eq!(s.active_comp().unwrap().renderer, Renderer::Classic3D);
+    s.execute("layer.lightSettings", json!({"layer": spot, "kind": "Environment"})).unwrap();
+    assert_eq!(s.active_comp().unwrap().renderer, Renderer::Advanced3D);
+    s.undo();
+    assert_eq!(s.active_comp().unwrap().renderer, Renderer::Classic3D);
+    assert_eq!(s.active_comp().unwrap().layer(effectcraft_project::LayerId(spot)).unwrap().source, LayerSource::Light { kind: LightKind::Spot });
+    // Other light types never switch it.
+    s.execute("layer.newLight", json!({"kind": "Point"})).unwrap();
+    assert_eq!(s.active_comp().unwrap().renderer, Renderer::Classic3D);
+    // Switching back to Classic 3D with an Environment light in the comp explains itself.
+    let env = s.execute("layer.newLight", json!({"kind": "Environment"})).unwrap()["layer"].as_u64().unwrap();
+    toasts(&mut s);
+    s.execute("comp.renderer", json!({"renderer": "classic3d"})).unwrap();
+    assert!(toasts(&mut s).iter().any(|m| m.contains("Environment light")), "the Classic 3D limit is explained");
+    // Editing that Environment light (no type change) leaves the renderer the user chose.
+    s.execute("layer.lightSettings", json!({"layer": env, "intensity": 80})).unwrap();
+    assert_eq!(s.active_comp().unwrap().renderer, Renderer::Classic3D, "an ordinary edit doesn't re-switch");
+    assert!(toasts(&mut s).is_empty(), "and doesn't toast either");
+}
+
+/// An Environment light takes Casts Shadows (with Shadow Darkness and Diffusion) like every
+/// other light — the Light Settings dialog offers them for all types but Ambient — and keeps no
+/// Falloff, which an environment light shining from every direction has no use for (#2436).
+#[test]
+fn environment_light_takes_shadow_options_but_no_falloff() {
+    let mut s = session();
+    let env = s.execute("layer.newLight", json!({"kind": "Environment", "castsShadows": true, "shadowDarkness": 60, "shadowDiffusion": 12})).unwrap()["layer"]
+        .as_u64()
+        .unwrap();
+    assert!(prop(&s, env, "lightOptions/castsShadows").as_bool());
+    assert_eq!(prop(&s, env, "lightOptions/shadowDarkness").as_f64(), 60.0);
+    assert_eq!(prop(&s, env, "lightOptions/shadowDiffusion").as_f64(), 12.0);
+    assert!(
+        s.active_comp().unwrap().layer(effectcraft_project::LayerId(env)).unwrap().props.prop("lightOptions/falloff").is_none(),
+        "an environment light has no Falloff"
+    );
+    // The shadow values carry over when the type changes, both ways.
+    s.execute("layer.lightSettings", json!({"layer": env, "kind": "Spot", "coneAngle": 70})).unwrap();
+    assert!(prop(&s, env, "lightOptions/castsShadows").as_bool());
+    assert_eq!(prop(&s, env, "lightOptions/shadowDarkness").as_f64(), 60.0);
+    assert_eq!(prop(&s, env, "lightOptions/coneAngle").as_f64(), 70.0);
+    s.execute("layer.lightSettings", json!({"layer": env, "kind": "Environment"})).unwrap();
+    assert!(prop(&s, env, "lightOptions/castsShadows").as_bool());
+    assert_eq!(prop(&s, env, "lightOptions/source").as_layer(), None, "back to Environment: it has a Source again");
+    s.undo();
+    assert!(
+        s.active_comp().unwrap().layer(effectcraft_project::LayerId(env)).unwrap().props.prop("lightOptions/coneAngle").is_some(),
+        "back to Spot: it has a Cone Angle again"
+    );
+}
+
 #[test]
 fn three_d_switch_undo_redo() {
     let mut s = session();