Merge main into #2268; import both layers_or and popup_options, drop main's now-unreachable post-duplicate end_edit (the PR ends the edit first), adapt tests to main's kept empty Type-tool layer (f262e39c6)

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

crates/engine/src/cmd/anim.rs

@@ -45,6 +45,7 @@ fn copy(s: &mut Session, _: &Value) -> Result<Value> {
         clip.push(KeyClip { layer: lid, path, keys });
     }
     let n: usize = clip.iter().map(|c| c.keys.len()).sum();
+    s.state.keyframe_text = crate::keyframe_text::text(&s.project, comp, &s.state.selected_keys, &[]);
     s.state.key_clipboard = clip;
     s.state.clip_is_keys = true;
     Ok(json!(n))

crates/engine/src/cmd/anim_presets.rs

@@ -1,6 +1,7 @@
 //! EffectCraft's own animation preset library (Effects & Presets ▸ * Animation Presets): the
 //! Transitions category (original presets built on our Transition effects and layer opacity) and
-//! the Backgrounds category (generators, noise and colour effects driven by expressions).
+//! the Backgrounds category (generators, noise and colour effects driven by expressions) and the
+//! Behaviors category (transform and opacity driven by expressions, no effects).
 //!
 //! Each preset adds effects (with values and keyframes) and/or keys layer properties, starting
 //! at the current time, on every selected layer. The library is data
@@ -26,13 +27,17 @@ pub const TRANSITIONS_JSON: &str = include_str!("../../presets/transitions.json"
 /// The original background presets (`presets/backgrounds.json`).
 pub const BACKGROUNDS_JSON: &str = include_str!("../../presets/backgrounds.json");
 
+/// The original behavior presets (`presets/behaviors.json`): expression-driven motion on a layer's
+/// transform and opacity, no effects.
+pub const BEHAVIORS_JSON: &str = include_str!("../../presets/behaviors.json");
+
 /// Keys per animated property, so a hostile inline preset can't allocate without bound.
 const MAX_KEYS: usize = 256;
 /// Longest expression text an inline preset may carry.
 const MAX_EXPR: usize = 4096;
 
 fn presets() -> Vec<Value> {
-    [TRANSITIONS_JSON, BACKGROUNDS_JSON]
+    [TRANSITIONS_JSON, BACKGROUNDS_JSON, BEHAVIORS_JSON]
         .iter()
         .flat_map(|src| serde_json::from_str::<Value>(src).ok().and_then(|v| v.get("presets").and_then(Value::as_array).cloned()).unwrap_or_default())
         .collect()

crates/engine/src/cmd/animation.rs

@@ -10,11 +10,16 @@ use effectcraft_project::{GroupKind, Layer, LayerId, LayerSource, Node, Project,
 use effectcraft_time::Tick;
 use serde_json::{Value, json};
 
+use super::effect::{effect_time_error, retime_effect};
 use super::{CommandSpec, bad, frontend, has_comp, has_keys, has_layers, layer_mut, layers_p, match_path_of, resolve_effect_path, selected_leaf_props, str_p};
 use crate::{EngineError, KeyRef, Result, Session, cmd};
 
 /// Preset file format version tag (`*.ecpreset`, JSON).
 pub const PRESET_TAG: &str = "effectcraftAnimationPreset";
+/// The preset format version that `anim.savePreset` writes.
+pub const PRESET_VERSION: u64 = 2;
+/// The first preset version that stores effect keys relative to the earliest key (#1971).
+const RELATIVE_EFFECT_KEYS: u64 = 2;
 
 fn has_selected_props(s: &Session) -> std::result::Result<(), String> {
     has_comp(s)?;
@@ -45,13 +50,26 @@ fn selected_effects(s: &Session) -> Vec<(LayerId, PropGroup)> {
         .collect()
 }
 
+/// The earliest key anywhere in `groups`, nested controls included.
+fn earliest_key<'a>(groups: impl IntoIterator<Item = &'a PropGroup>) -> Option<Tick> {
+    let mut first: Option<Tick> = None;
+    for g in groups {
+        g.walk("", &mut |_, pr| {
+            if let Some(t) = pr.keys.iter().map(|k| k.time).min() {
+                first = Some(first.map_or(t, |f| f.min(t)));
+            }
+        });
+    }
+    first
+}
+
 // ---------------------------------------------------------------- presets
 
 fn save_preset(s: &mut Session, p: &Value) -> Result<Value> {
     let path = str_p(p, "path").ok_or_else(|| bad("anim.savePreset", "missing `path`"))?.to_string();
     let comp = s.active_comp().ok_or(EngineError::NoComp)?;
     let t = s.time();
-    let effects: Vec<(LayerId, PropGroup)> = selected_effects(s);
+    let mut effects: Vec<(LayerId, PropGroup)> = selected_effects(s);
     let effect_uids: Vec<Uid> = effects.iter().map(|(_, g)| g.uid).collect();
     let mut props = vec![];
     for (lid, uid) in selected_leaf_props(s) {
@@ -67,7 +85,11 @@ fn save_preset(s: &mut Session, p: &Value) -> Result<Value> {
         return Err(bad("anim.savePreset", "select properties or effects to save"));
     }
     // Key times are stored relative to the earliest key so the preset applies at the CTI.
-    let first = props.iter().flat_map(|(_, _, pr)| pr.keys.iter().map(|k| k.time)).min().unwrap_or(Tick::ZERO);
+    let first =
+        props.iter().flat_map(|(_, _, pr)| pr.keys.iter().map(|k| k.time)).chain(earliest_key(effects.iter().map(|(_, g)| g))).min().unwrap_or(Tick::ZERO);
+    for (_, g) in &mut effects {
+        retime_effect(g, 1.0, "anim.savePreset", |t| Ok(Tick(t.0.checked_sub(first.0).ok_or_else(|| effect_time_error("anim.savePreset"))?)))?;
+    }
     let props_json: Vec<Value> = props
         .iter()
         .map(|(_, mp, pr)| {
@@ -82,12 +104,27 @@ fn save_preset(s: &mut Session, p: &Value) -> Result<Value> {
     let name = str_p(p, "name")
         .map(str::to_string)
         .unwrap_or_else(|| std::path::Path::new(&path).file_stem().map(|s| s.to_string_lossy().to_string()).unwrap_or_default());
-    let doc = json!({PRESET_TAG: 1, "name": name, "properties": props_json, "effects": fx_json});
+    let doc = json!({PRESET_TAG: PRESET_VERSION, "name": name, "properties": props_json, "effects": fx_json});
     let text = serde_json::to_string_pretty(&doc).unwrap_or_default();
     s.services.write_file(&path, text.as_bytes()).map_err(|e| EngineError::Other(format!("cannot write {path}: {e}")))?;
     Ok(json!({"path": path, "properties": props.len(), "effects": effects.len()}))
 }
 
+/// Rewrite an effect property path in a preset (`effects/<effect id>[#n]/<param>`) to the current
+/// parameter id when it names a parameter that the effect has since renamed or moved into a
+/// twirl-down group. Any other path comes back unchanged.
+fn upgrade_effect_path(path: &str) -> String {
+    let Some((seg, tail)) = path.strip_prefix("effects/").and_then(|r| r.split_once('/')) else { return path.to_string() };
+    let effect = match seg.rsplit_once('#') {
+        Some((m, n)) if !m.is_empty() && n.parse::<usize>().is_ok() => m,
+        _ => seg,
+    };
+    match effectcraft_effects::find(effect).and_then(|spec| effectcraft_effects::migrate::current_param_id(spec, tail)) {
+        Some(id) if id != tail => format!("effects/{seg}/{id}"),
+        _ => path.to_string(),
+    }
+}
+
 fn apply_preset(s: &mut Session, p: &Value) -> Result<Value> {
     let doc: Value = match (p.get("preset"), str_p(p, "path")) {
         (Some(v), _) => v.clone(),
@@ -110,14 +147,22 @@ fn apply_preset(s: &mut Session, p: &Value) -> Result<Value> {
         s.save_prefs();
         s.prefs_revision += 1;
     }
-    let effects: Vec<PropGroup> =
+    let mut effects: Vec<PropGroup> =
         doc["effects"].as_array().map(|a| a.iter().filter_map(|v| serde_json::from_value(v.clone()).ok()).collect()).unwrap_or_default();
+    // Older presets stored effect keys at the source layer's times.
+    if doc[PRESET_TAG].as_u64().unwrap_or(1) < RELATIVE_EFFECT_KEYS
+        && let Some(first) = earliest_key(&effects)
+    {
+        for g in &mut effects {
+            retime_effect(g, 1.0, "anim.applyPreset", |t| Ok(Tick(t.0.checked_sub(first.0).ok_or_else(|| effect_time_error("anim.applyPreset"))?)))?;
+        }
+    }
     let props: Vec<(String, Property)> = doc["properties"]
         .as_array()
         .map(|a| {
             a.iter()
                 .filter_map(|v| {
-                    let path = v["path"].as_str()?.to_string();
+                    let path = upgrade_effect_path(v["path"].as_str()?);
                     let value: KV = serde_json::from_value(v["value"].clone()).ok()?;
                     let keys: Vec<Keyframe> = serde_json::from_value(v["keys"].clone()).unwrap_or_default();
                     let expr = serde_json::from_value(v["expression"].clone()).ok().flatten();
@@ -130,16 +175,30 @@ fn apply_preset(s: &mut Session, p: &Value) -> Result<Value> {
         })
         .unwrap_or_default();
     let t = s.time();
+    // Effect bounds per layer size the point defaults of parameters added since the preset was saved.
+    let comp = s.project.comp(cid).ok_or(EngineError::NoComp)?;
+    let sizes: BTreeMap<LayerId, [f64; 2]> =
+        ids.iter().filter_map(|lid| comp.layer(*lid).map(|l| (*lid, effectcraft_render::effect_bounds(&s.project, comp, l).0))).collect();
     let mut applied = 0;
     let mut skipped = vec![];
     s.edit("Apply Animation Preset", None, |proj, _| {
         let mut next = proj.next_id;
         for lid in &ids {
+            let size = sizes.get(lid).copied().unwrap_or([100.0, 100.0]);
             let l = layer_mut(proj, cid, *lid)?;
             let lt = l.layer_time(t);
             if let Some(fx) = l.props.sub_mut("effects") {
                 for g in &effects {
                     let mut g = g.clone();
+                    // Effects saved by an earlier version get the upgrade a project gets on open.
+                    let spec = match &g.kind {
+                        GroupKind::Effect { effect } => effectcraft_effects::find(effect),
+                        _ => None,
+                    };
+                    if let Some(spec) = spec {
+                        effectcraft_effects::migrate::upgrade_instance(spec, &mut g, &mut Ids(&mut next), size);
+                    }
+                    retime_effect(&mut g, 1.0, "anim.applyPreset", |t| Ok(Tick(t.0.checked_add(lt.0).ok_or_else(|| effect_time_error("anim.applyPreset"))?)))?;
                     g.reassign_uids(&mut next);
                     next += 1;
                     fx.children.push(Node::Group(g));
@@ -184,7 +243,7 @@ fn add_keyframe(s: &mut Session, _: &Value) -> Result<Value> {
     }
     let cid = s.active_comp_id().ok_or(EngineError::NoComp)?;
     let t = s.time();
-    let n = s.edit("Add Keyframe", None, |proj, _| {
+    let n = s.edit("Add Keyframe", None, |proj, state| {
         let mut n = 0;
         for (lid, uid) in &targets {
             let l = layer_mut(proj, cid, *lid)?;
@@ -200,6 +259,9 @@ fn add_keyframe(s: &mut Session, _: &Value) -> Result<Value> {
                 pr.set_value_at(lt, v);
             }
             n += 1;
+            if pr.match_id == "type" {
+                super::prop::sync_polystar_property(proj, state, cid, *lid, *uid, t)?;
+            }
         }
         Ok(n)
     })?;

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/blender.rs

@@ -0,0 +1,295 @@
+//! Camera-solve interchange through Blender's public Python API. The generated script is
+//! original MIT OR Apache-2.0 code; no Blender implementation is read or embedded.
+
+use std::path::Path;
+
+use effectcraft_effects::camera_tracker as ct;
+use effectcraft_project::{Footage, FootageKind, ItemId, ItemKind, Layer, LayerId, LayerSource, Uid};
+use effectcraft_render::EvalCtx;
+use effectcraft_time::Tick;
+use effectcraft_track::camtrack::{CameraSolve, linalg};
+use serde_json::{Value, json};
+
+mod validate;
+
+use super::{b_p, bad, f_p, str_p};
+use crate::{EngineError, Result, Session};
+
+const CMD: &str = "camera.exportBlender";
+const MAX_FRAMES: usize = 100_000;
+const MAX_POINTS: usize = 100_000;
+const MAX_JSON: usize = 64 * 1024 * 1024;
+const MAX_FRAME: i64 = 1_048_574;
+
+fn number(p: &Value, key: &str, default: f64, min: f64, max: f64) -> Result<f64> {
+    let v = match p.get(key) {
+        None => default,
+        Some(_) => f_p(p, key).ok_or_else(|| bad(CMD, format!("{key}: expected a number")))?,
+    };
+    if !v.is_finite() || !(min..=max).contains(&v) {
+        return Err(bad(CMD, format!("{key}: expected {min}..{max}")));
+    }
+    Ok(v)
+}
+
+fn finite(values: impl IntoIterator<Item = f64>) -> Result<()> {
+    if values.into_iter().any(|v| !v.is_finite() || v.abs() > 1e12) {
+        return Err(bad(CMD, "invalid or excessive numeric camera/scene data; re-analyze the tracker"));
+    }
+    Ok(())
+}
+
+/// Right-handed EffectCraft world (right, down, forward) → Blender (right, forward, up).
+fn position(p: [f64; 3], scale: f64) -> [f64; 3] {
+    [p[0] * scale, p[2] * scale, -p[1] * scale]
+}
+
+fn media_path(s: &Session, path: &str) -> Result<String> {
+    if path.is_empty() || path.contains('\0') {
+        return Err(bad(CMD, "the source footage has no valid file path; relink it before exporting"));
+    }
+    let path = Path::new(path);
+    if path.is_absolute() || cfg!(target_arch = "wasm32") {
+        return Ok(path.to_string_lossy().into_owned());
+    }
+    let cwd = std::env::current_dir().map_err(|e| bad(CMD, format!("cannot resolve footage path: {e}")))?;
+    let base = s.path.as_deref().and_then(|p| Path::new(p).parent()).map(|p| cwd.join(p)).unwrap_or(cwd);
+    Ok(base.join(path).to_string_lossy().into_owned())
+}
+
+pub(super) fn export(s: &mut Session, p: &Value, cid: ItemId, lid: LayerId, uid: Uid) -> Result<Value> {
+    if s.running_for_script() && !s.prefs.scripting.allow_scripts_write_files {
+        return Err(bad(CMD, "scripts can't export files unless Settings ▸ Scripting & Expressions ▸ Allow Scripts to Write Files and Access Network is on"));
+    }
+    let options = Options::parse(p)?;
+    let Options { path, sensor, units, start, include_points } = options;
+    if s.camera_target().is_some_and(|(c, l, u)| (c, l, u) == (cid, lid, uid)) && s.is_camera_analyzing() || s.camera_pending.contains(&(cid, lid, uid)) {
+        return Err(bad(CMD, "wait for this tracker's analysis to finish before exporting"));
+    }
+    let comp = s.project.comp(cid).ok_or(EngineError::NoComp)?;
+    let layer = comp.layer(lid).ok_or_else(|| bad(CMD, "tracked layer missing"))?;
+    let g = layer.props.find_group(uid).ok_or_else(|| bad(CMD, "tracker missing"))?;
+    for name in [ct::SOLVE, ct::TRACKS] {
+        if g.prop(name).is_some_and(|p| matches!(&p.value, effectcraft_keyframe::Value::Str(v) if v.len() > MAX_JSON)) {
+            return Err(bad(CMD, "tracking data exceeds the 64 MiB export limit"));
+        }
+    }
+    let params = crate::camera_track::static_params(g);
+    let solve = ct::solve(&params).ok_or_else(|| bad(CMD, "the camera is not solved yet; analyze the tracker first"))?;
+    let (lo, end) = validate::timing(comp, layer, &solve, start)?;
+    let Source { footage, path: source_path, fps: source_fps, count: source_count } = source(s, layer, &solve, path)?;
+    validate::geometry(&solve, sensor)?;
+    let camera = params
+        .get(ct::CAMERA)
+        .map(|v| v.as_f64())
+        .filter(|v| v.is_finite() && *v > 0.0 && *v <= u64::MAX as f64)
+        .and_then(|id| comp.layer(LayerId(id as u64)))
+        .filter(|l| l.is_camera());
+    let warnings = scene_warnings(camera, &solve, footage);
+    let ctx = EvalCtx { expr: s.expr.as_deref(), ..EvalCtx::new(&s.project, cid, comp, lo) };
+    let (frames, world) = bake_frames(&ctx, layer, &solve, camera, &options, footage, source_count)?;
+    let mut points = Vec::new();
+    for point in &solve.points {
+        finite(point.pos.into_iter().chain([point.error as f64]))?;
+        if point.first > point.last || point.last as usize >= solve.frames.len() {
+            return Err(bad(CMD, "invalid solved point frame range; re-analyze the tracker"));
+        }
+        let location = position(world.apply(point.pos), units);
+        finite(location)?;
+        if include_points {
+            points.push(json!({"id": point.id, "location": location, "error": point.error,
+                "first": start.saturating_add(point.first as i64), "last": start.saturating_add(point.last as i64)}));
+        }
+    }
+    let tracks = ct::tracks(&params);
+    if tracks.as_ref().is_some_and(|t| t.tracks.len() > MAX_POINTS || t.tracks.iter().any(|t| t.pts.len() > MAX_FRAMES)) {
+        return Err(bad(CMD, "2D tracks exceed export limits"));
+    }
+    let markers: Vec<Value> = comp
+        .markers
+        .iter()
+        .filter_map(|m| {
+            let frame = start.saturating_add(comp.frame_rate.frame_at(m.time).saturating_sub(comp.frame_rate.frame_at(lo)));
+            if (start..=end).contains(&frame) { Some(json!({"name": m.comment, "frame": frame})) } else { None }
+        })
+        .collect();
+    let payload = json!({"version": 1, "name": format!("{} — {}", s.project.item(cid).map(|i| i.name.as_str()).unwrap_or("Shot"), layer.name),
+        "resolution": solve.size, "fpsNumerator": comp.frame_rate.num, "fpsDenominator": comp.frame_rate.den,
+        "startFrame": start, "endFrame": end, "sensorWidth": sensor, "unitScale": units,
+        "media": {"path": source_path, "kind": if footage.kind == FootageKind::Still {"FILE"} else {"MOVIE"},
+            "fps": source_fps, "nativeRate": footage.native_rate, "pixelAspect": footage.pixel_aspect, "timecode": footage.start_timecode,
+            "frameCount": source_count, "loopCount": footage.loop_count},
+        "frames": frames, "points": points, "markers": markers, "ground": solve.ground.is_some(),
+        "groundSize": world.s * units, "shutter": comp.shutter_angle / 360.0, "shutterPhase": comp.shutter_phase,
+        "solve": solve, "tracks": if include_points { tracks.as_deref() } else { None },
+        "warnings": warnings});
+    let data = serde_json::to_string(&payload).map_err(|e| bad(CMD, format!("cannot serialize scene: {e}")))?;
+    if data.len() > MAX_JSON {
+        return Err(bad(CMD, "scene exceeds the 64 MiB script limit; disable includePoints or split the shot"));
+    }
+    let quoted = serde_json::to_string(&data).map_err(|e| bad(CMD, format!("cannot encode scene: {e}")))?;
+    let script = include_str!("blender_scene.py").replace("__EFFECTCRAFT_DATA__", &quoted);
+    s.services.write_file(path, script.as_bytes()).map_err(|e| bad(CMD, format!("cannot write {path}: {e}")))?;
+    Ok(json!({"path": path, "bytes": script.len(), "frames": frames.len(), "points": points.len(), "warnings": warnings}))
+}
+
+struct Options<'a> {
+    path: &'a str,
+    sensor: f64,
+    units: f64,
+    start: i64,
+    include_points: bool,
+}
+
+impl<'a> Options<'a> {
+    fn parse(p: &'a Value) -> Result<Self> {
+        let path = str_p(p, "path").filter(|p| !p.is_empty() && !p.contains('\0')).ok_or_else(|| bad(CMD, "missing `path` (.py)"))?;
+        if !Path::new(path).extension().is_some_and(|e| e.eq_ignore_ascii_case("py")) {
+            return Err(bad(CMD, "the export path must end in .py"));
+        }
+        let sensor = number(p, "sensorWidth", 36.0, 1.0, 1000.0)?;
+        let units = number(p, "unitScale", 0.01, 0.000_001, 1000.0)?;
+        let start = match p.get("startFrame") {
+            None => 1,
+            Some(v) => v.as_i64().filter(|n| (1..=MAX_FRAME).contains(n)).ok_or_else(|| bad(CMD, "startFrame: expected a positive Blender frame number"))?,
+        };
+        let include_points = match p.get("includePoints") {
+            Some(v) if !v.is_boolean() => return Err(bad(CMD, "includePoints: expected a boolean")),
+            _ => b_p(p, "includePoints").unwrap_or(true),
+        };
+        Ok(Self { path, sensor, units, start, include_points })
+    }
+}
+
+struct Source<'a> {
+    footage: &'a Footage,
+    path: String,
+    fps: f64,
+    count: i64,
+}
+
+fn source<'a>(s: &'a Session, layer: &Layer, solve: &CameraSolve, path: &str) -> Result<Source<'a>> {
+    let footage = match layer.source {
+        LayerSource::Footage { item } => s.project.item(item).and_then(|i| match &i.kind {
+            ItemKind::Footage(f) => Some(f),
+            _ => None,
+        }),
+        _ => None,
+    }
+    .filter(|f| f.has_video && matches!(f.kind, FootageKind::Video | FootageKind::Still));
+    let footage = footage
+        .ok_or_else(|| bad(CMD, "Blender background export needs a video or still-footage layer; render precomps/sequences to a video and track that video"))?;
+    let source_path = media_path(s, &footage.path)?;
+    if Path::new(path) == Path::new(&source_path) {
+        return Err(bad(CMD, "the export path must differ from the source footage"));
+    }
+    if footage.width as f64 != solve.size[0] || footage.height as f64 != solve.size[1] {
+        return Err(bad(CMD, "the analysis image differs from the original footage dimensions; render the tracker's input to a video and track that video"));
+    }
+    let source_fps = footage.frame_rate.as_f64();
+    if footage.frame_rate.num <= 0 || footage.frame_rate.den <= 0 || !source_fps.is_finite() || source_fps <= 0.0 {
+        return Err(bad(CMD, "invalid source footage frame rate"));
+    }
+    // Same frame selection as the media pool: interpreted FPS, rounded per-loop frame count,
+    // clamp to the total loop range, then wrap. Native FPS does not change the frame index.
+    let divisor = (effectcraft_time::TICKS_PER_SECOND as i128).saturating_mul(footage.frame_rate.den as i128);
+    let source_count = (footage.duration.0 as i128).saturating_mul(footage.frame_rate.num as i128).saturating_add(divisor / 2) / divisor;
+    let source_count = if footage.kind == FootageKind::Still { 1 } else { source_count };
+    if !(1..=MAX_FRAME as i128).contains(&source_count) {
+        return Err(bad(CMD, "invalid footage duration or footage exceeds Blender's frame range; trim/render the source video first"));
+    }
+    let source_count = source_count as i64;
+    Ok(Source { footage, path: source_path, fps: source_fps, count: source_count })
+}
+
+fn scene_warnings(camera: Option<&Layer>, solve: &CameraSolve, footage: &Footage) -> Vec<String> {
+    let mut warnings = vec![
+        "Sensor width is assumed (36 mm by default); monocular tracking cannot recover physical sensor size or absolute scene scale.".to_string(),
+        "The original footage is referenced, not embedded or rendered: masks and effects before the tracker are not baked. Relink the video if moving this script.".to_string(),
+    ];
+    if camera.is_none() {
+        warnings
+            .push("No linked tracker camera: focus uses the default scene depth, DOF is off; optical focus cannot be recovered from feature tracks.".into());
+    } else {
+        warnings.push("Focus/iris settings are sampled from the linked camera; pose and lens come from the tracker solve. Blender's physical DOF is an approximation of EffectCraft's blur model.".into());
+    }
+    if solve.distortion.is_some_and(|d| !d.is_none()) {
+        warnings.push("Radial distortion is preserved as metadata (Brown k1/k2, half-diagonal normalization), not applied to Blender's pinhole camera. Use an undistorted plate for exact alignment.".into());
+    }
+    if (footage.pixel_aspect - 1.0).abs() > 1e-6 {
+        warnings.push("The tracker solves square pixels: export uses square pixels; original footage pixel aspect is retained in metadata.".into());
+    }
+    warnings
+}
+
+/// Bake the solved camera and the linked camera's optical settings at exact composition ticks.
+fn bake_frames(
+    ctx0: &EvalCtx<'_>,
+    layer: &Layer,
+    solve: &CameraSolve,
+    camera: Option<&Layer>,
+    options: &Options<'_>,
+    footage: &Footage,
+    source_count: i64,
+) -> Result<(Vec<Value>, linalg::Similarity)> {
+    let comp = ctx0.comp;
+    let lo = ctx0.time;
+    let fd = comp.frame_duration();
+    let sensor = options.sensor;
+    let units = options.units;
+    let start = options.start;
+    let first = solve.frames.first().ok_or_else(|| bad(CMD, "the camera solve is empty"))?;
+    let m = ctx0.world_matrix(layer).0;
+    let layer_scale = m[0][0].hypot(m[1][0]);
+    finite([layer_scale])?;
+    if layer_scale <= 1e-9 {
+        return Err(bad(CMD, "the tracked layer has zero scale"));
+    }
+    let world = solve.world([comp.width as f64, comp.height as f64], first.focal * layer_scale);
+    finite([world.s * units])?;
+    let mut frames = Vec::with_capacity(solve.frames.len());
+    for (i, frame) in solve.frames.iter().enumerate() {
+        let time = Tick(lo.0.saturating_add(fd.0.saturating_mul(i as i64)));
+        let ctx = ctx0.at(time);
+        let pose = linalg::mm(&world.r, &linalg::mt(&frame.r()));
+        let right = position(linalg::mv(&pose, [1.0, 0.0, 0.0]), 1.0);
+        let up = position(linalg::mv(&pose, [0.0, -1.0, 0.0]), 1.0);
+        let back = position(linalg::mv(&pose, [0.0, 0.0, -1.0]), 1.0);
+        let location = position(world.apply(frame.center), units);
+        let lens = frame.focal * sensor / solve.size[0];
+        let opts = camera.and_then(|l| l.props.sub("cameraOptions").map(|g| (l, g)));
+        let value = |key: &str, fallback: f64| opts.map(|(l, g)| ctx.f(l, g, key, fallback)).unwrap_or(fallback);
+        let focus = value("focusDistance", world.s) * units;
+        let aperture = value("aperture", 0.0);
+        let zoom = value("zoom", frame.focal * layer_scale);
+        // Match Camera Settings' f-stop conversion: focal_for_zoom uses a 36 mm film width,
+        // and the aperture UI is mm scaled by comp_width / 1920 (not a world-space diameter).
+        let aperture_mm = aperture * 1920.0 / comp.width as f64;
+        let fstop = if aperture_mm > 0.0 { (zoom * 36.0 / comp.width as f64) / aperture_mm } else { 2.8 };
+        let rotation = value("irisRotation", 0.0).to_radians();
+        let ratio = value("irisAspectRatio", 1.0);
+        let shape = opts.map(|(l, g)| ctx.e(l, g, "irisShape")).unwrap_or(0);
+        let blades = match shape {
+            0 => 4,
+            1..=8 => shape.saturating_add(2),
+            _ => return Err(bad(CMD, "invalid iris shape")),
+        };
+        let dof = opts.is_some_and(|(l, g)| ctx.b(l, g, "dof")) && aperture > 0.0 && value("blurLevel", 100.0) > 0.0;
+        let source_time = ctx.source_time(layer);
+        let source_frame = if footage.kind == FootageKind::Still {
+            0
+        } else {
+            footage.frame_rate.frame_at(source_time).clamp(0, source_count.saturating_mul(footage.loop_count.max(1) as i64).saturating_sub(1)) % source_count
+        };
+        finite(location.into_iter().chain([focus, aperture, zoom, fstop, rotation, ratio, value("blurLevel", 100.0), value("irisRoundness", 0.0)]))?;
+        if focus <= 0.0 || !(0.01..=100.0).contains(&ratio) || !(0.01..=1e6).contains(&fstop) {
+            return Err(bad(CMD, "focus, f-stop or iris aspect is outside Blender's supported range"));
+        }
+        frames.push(json!({"frame": start + i as i64, "timeTicks": time.0, "sourceFrame": source_frame,
+            "location": location, "rotation": [right, up, back], "lens": lens, "focus": focus, "dof": dof,
+            "fstop": fstop, "blades": blades, "irisRotation": rotation, "irisRatio": ratio,
+            "sourceAperture": aperture, "sourceZoom": zoom,
+            "blurLevel": value("blurLevel", 100.0), "irisRoundness": value("irisRoundness", 0.0)}));
+    }
+    Ok((frames, world))
+}

crates/engine/src/cmd/blender/validate.rs

@@ -0,0 +1,71 @@
+//! Validate solved geometry and its correspondence to the current layer timing.
+
+use effectcraft_project::{Comp, Layer};
+use effectcraft_time::Tick;
+use effectcraft_track::camtrack::{CameraSolve, linalg};
+
+use super::{CMD, MAX_FRAME, MAX_FRAMES, MAX_POINTS, bad, finite};
+use crate::Result;
+
+pub(super) fn timing(comp: &Comp, layer: &Layer, solve: &CameraSolve, start: i64) -> Result<(Tick, i64)> {
+    if solve.frames.len() > MAX_FRAMES || solve.points.len() > MAX_POINTS {
+        return Err(bad(CMD, "export is limited to 100,000 frames and 100,000 points; split the shot"));
+    }
+    if solve.size.iter().any(|v| !v.is_finite() || *v < 4.0 || *v > 65_536.0 || v.fract() != 0.0) {
+        return Err(bad(CMD, "invalid tracking resolution (expected 4..65536 whole pixels)"));
+    }
+    let fps = comp.frame_rate.as_f64();
+    if comp.frame_rate.num <= 0 || comp.frame_rate.den <= 0 || !fps.is_finite() || !(1.0..=1000.0).contains(&fps) {
+        return Err(bad(CMD, "invalid composition frame rate (expected 1..1000 fps)"));
+    }
+    let end = start
+        .checked_add(solve.frames.len() as i64)
+        .and_then(|n| n.checked_sub(1))
+        .filter(|n| *n <= MAX_FRAME)
+        .ok_or_else(|| bad(CMD, "the baked animation exceeds Blender's frame range"))?;
+    finite([solve.start, solve.frame_duration, solve.average_error, layer.stretch, comp.shutter_angle, comp.shutter_phase])?;
+    if layer.stretch == 0.0 || comp.width == 0 || comp.height == 0 {
+        return Err(bad(CMD, "invalid composition dimensions or zero layer stretch"));
+    }
+    let lo = comp.frame_rate.snap_nearest(layer.in_point.max(Tick::ZERO));
+    let hi = layer.out_point.min(comp.duration);
+    let fd = comp.frame_duration();
+    if fd.0 <= 0 || lo >= hi {
+        return Err(bad(CMD, "the tracked layer has no active frames"));
+    }
+    let expected = ((hi.0 as i128 - lo.0 as i128 + fd.0 as i128 - 1) / fd.0 as i128) as u128;
+    if expected != solve.frames.len() as u128 {
+        return Err(bad(CMD, "the solve no longer matches the layer's frame range; re-analyze the tracker"));
+    }
+    let dt = (layer.layer_time(lo + fd) - layer.layer_time(lo)).seconds();
+    if (solve.start - layer.layer_time(lo).seconds()).abs() > 1e-6 || solve.frames.len() > 1 && (solve.frame_duration - dt).abs() > 1e-6 {
+        return Err(bad(CMD, "the solve no longer matches the layer's timing; re-analyze the tracker"));
+    }
+    Ok((lo, end))
+}
+
+pub(super) fn geometry(solve: &CameraSolve, sensor: f64) -> Result<()> {
+    for frame in &solve.frames {
+        finite(frame.rot.into_iter().chain(frame.center).chain([frame.focal]))?;
+        if !frame.solved || frame.focal <= 0.0 {
+            return Err(bad(CMD, "the solve contains unsolved frames or invalid focal lengths; re-analyze the tracker"));
+        }
+        let mm = sensor * frame.focal / solve.size[0];
+        if !(1.0..=5000.0).contains(&mm) {
+            return Err(bad(CMD, "lens outside Blender's 1..5000 mm range; choose another sensorWidth"));
+        }
+    }
+    if let Some(ground) = &solve.ground {
+        finite(ground.origin.into_iter().chain(ground.normal).chain(ground.x_axis))?;
+        if (linalg::norm(ground.normal) - 1.0).abs() > 1e-4
+            || (linalg::norm(ground.x_axis) - 1.0).abs() > 1e-4
+            || linalg::dot(ground.normal, ground.x_axis).abs() > 1e-4
+        {
+            return Err(bad(CMD, "invalid ground-plane basis; set the ground plane again"));
+        }
+    }
+    if let Some(d) = &solve.distortion {
+        finite([d.k1, d.k2, d.radius])?;
+    }
+    Ok(())
+}

crates/engine/src/cmd/blender_scene.py

@@ -0,0 +1,204 @@
+# EffectCraft camera tracker → Blender, original code under MIT OR Apache-2.0.
+# Run in Blender's Scripting workspace (Open, Run Script), or:
+# blender --background --python "Tracked Scene.py"
+# Creates a NEW scene; existing scenes and objects are preserved. Save the .blend yourself.
+# Public API types: bpy.types.Camera, bpy.types.ImageUser
+import json
+import math
+import os
+
+import bpy
+from mathutils import Matrix
+
+DATA = json.loads(__EFFECTCRAFT_DATA__)
+
+
+def _curves(owner):
+    """Blender 4.0–4.3 legacy actions and 4.4+/5.x layered actions."""
+    anim = owner.animation_data
+    if anim is None or anim.action is None:
+        return
+    action = anim.action
+    if getattr(action, "is_action_layered", False):
+        for layer in action.layers:
+            for strip in layer.strips:
+                if strip.type == 'KEYFRAME':
+                    bag = strip.channelbag(anim.action_slot)
+                    if bag is not None:
+                        yield from bag.fcurves
+    else:
+        yield from action.fcurves
+
+
+def _interpolation(owner):
+    for curve in _curves(owner):
+        # Footage indices and discrete switches must never interpolate between frames.
+        stepped = ("frame_offset" in curve.data_path or "use_dof" in curve.data_path
+                   or "aperture_blades" in curve.data_path)
+        for key in curve.keyframe_points:
+            key.interpolation = 'CONSTANT' if stepped else 'LINEAR'
+
+
+def _media_path():
+    original = DATA["media"]["path"]
+    candidates = [original]
+    # When sharing, place the video alongside the script or the .blend and run again.
+    script_path = globals().get("__file__", "")
+    if script_path:
+        candidates.append(os.path.join(os.path.dirname(os.path.abspath(script_path)),
+                                       os.path.basename(original)))
+    if bpy.data.filepath:
+        candidates.append(os.path.join(os.path.dirname(bpy.data.filepath),
+                                       os.path.basename(original)))
+    return next((p for p in candidates if os.path.isfile(p)), None)
+
+
+def import_scene():
+    if bpy.app.version < (4, 0, 0):
+        raise RuntimeError("EffectCraft scene import requires Blender 4.0 or newer")
+    scene = bpy.data.scenes.new(DATA["name"])
+    scene.frame_start = DATA["startFrame"]
+    scene.frame_end = DATA["endFrame"]
+    fps = DATA["fpsNumerator"] / DATA["fpsDenominator"]
+    scene.render.fps = max(1, round(fps))
+    scene.render.fps_base = scene.render.fps / fps
+    scene.render.resolution_x, scene.render.resolution_y = map(int, DATA["resolution"])
+    scene.render.resolution_percentage = 100
+    # The tracker assumes square pixels, regardless of the source's interpretation metadata.
+    scene.render.pixel_aspect_x = scene.render.pixel_aspect_y = 1.0
+    scene.render.film_transparent = True
+    scene.render.motion_blur_shutter = max(0.0, min(2.0, DATA["shutter"]))
+    scene.unit_settings.system = 'METRIC'
+    scene.unit_settings.scale_length = 1.0
+    scene["effectcraft_unit_scale"] = DATA["unitScale"]
+    scene["effectcraft_scale_is_arbitrary"] = True
+    scene["effectcraft_shutter_phase_degrees"] = DATA["shutterPhase"]
+
+    collection = bpy.data.collections.new("EffectCraft Tracking")
+    scene.collection.children.link(collection)
+    camera_data = bpy.data.cameras.new("3D Tracker Camera")
+    camera = bpy.data.objects.new("3D Tracker Camera", camera_data)
+    collection.objects.link(camera)
+    scene.camera = camera
+    camera.rotation_mode = 'QUATERNION'
+    camera_data.type = 'PERSP'
+    camera_data.sensor_fit = 'HORIZONTAL'
+    camera_data.sensor_width = DATA["sensorWidth"]
+    camera_data.sensor_height = (DATA["sensorWidth"] * DATA["resolution"][1]
+                                 / DATA["resolution"][0])
+    camera_data.show_background_images = True
+    camera_data.show_limits = True
+    extent = max([DATA["groundSize"], 1.0]
+                 + [math.dist(p["location"], f["location"])
+                    for p in DATA["points"][::max(1, len(DATA["points"]) // 100)]
+                    for f in DATA["frames"][::max(1, len(DATA["frames"]) // 10)]])
+    camera_data.clip_start = max(0.00001, min(0.1, extent / 10000.0))
+    camera_data.clip_end = max(1000.0, extent * 10.0)
+
+    previous = None
+    for sample in DATA["frames"]:
+        frame = sample["frame"]
+        camera.location = sample["location"]
+        # Exported right/up/back vectors are COLUMNS of Blender's local → world basis.
+        quaternion = Matrix(sample["rotation"]).transposed().to_quaternion()
+        if previous is not None and previous.dot(quaternion) < 0:
+            quaternion.negate()
+        camera.rotation_quaternion = quaternion
+        previous = quaternion.copy()
+        camera.keyframe_insert(data_path="location", frame=frame)
+        camera.keyframe_insert(data_path="rotation_quaternion", frame=frame)
+        camera_data.lens = sample["lens"]
+        camera_data.keyframe_insert(data_path="lens", frame=frame)
+        camera_data.dof.use_dof = sample["dof"]
+        camera_data.dof.focus_distance = sample["focus"]
+        camera_data.dof.aperture_fstop = sample["fstop"]
+        camera_data.dof.aperture_blades = sample["blades"]
+        camera_data.dof.aperture_rotation = (sample["irisRotation"] + math.pi) % math.tau - math.pi
+        camera_data.dof.aperture_ratio = sample["irisRatio"]
+        for prop in ("use_dof", "focus_distance", "aperture_fstop", "aperture_blades",
+                     "aperture_rotation", "aperture_ratio"):
+            camera_data.keyframe_insert(data_path="dof." + prop, frame=frame)
+
+    path = _media_path()
+    if path is not None:
+        try:
+            image = bpy.data.images.load(path, check_existing=False)
+            image.source = DATA["media"]["kind"]
+            background = camera_data.background_images.new()
+            background.source = 'IMAGE'
+            background.image = image
+            background.alpha = 1.0
+            background.display_depth = 'BACK'
+            background.frame_method = 'STRETCH'
+            user = background.image_user
+            user.use_auto_refresh = True
+            user.use_cyclic = False
+            user.frame_start = DATA["startFrame"]
+            user.frame_duration = max(1, min(1048574, image.frame_duration))
+            if image.source == 'MOVIE':
+                for sample in DATA["frames"]:
+                    # Blender uses 1-based image frames; sourceFrame is 0-based.
+                    user.frame_offset = sample["sourceFrame"] - (sample["frame"] - user.frame_start)
+                    camera_data.keyframe_insert(
+                        data_path="background_images[0].image_user.frame_offset",
+                        frame=sample["frame"])
+        except (RuntimeError, ValueError, OSError) as error:
+            DATA["warnings"].append("Blender could not load the background video: " + str(error))
+    else:
+        DATA["warnings"].append("Video not found: " + DATA["media"]["path"]
+                                + ". Place it beside this script or relink the camera background.")
+
+    if DATA["points"]:
+        mesh = bpy.data.meshes.new("Solved Track Points")
+        mesh.from_pydata([p["location"] for p in DATA["points"]], [], [])
+        mesh.update()
+        cloud = bpy.data.objects.new("Solved Track Points", mesh)
+        collection.objects.link(cloud)
+        cloud.show_in_front = True
+        cloud.hide_render = True
+        for name, kind, key in (("track_id", 'INT', "id"), ("reprojection_error", 'FLOAT', "error"),
+                                ("first_frame", 'INT', "first"), ("last_frame", 'INT', "last")):
+            attr = mesh.attributes.new(name=name, type=kind, domain='POINT')
+            for dest, point in zip(attr.data, DATA["points"]):
+                # Track IDs are u32 in EffectCraft; keep the full IDs in the JSON text too.
+                dest.value = point[key] if kind == 'FLOAT' else min(2147483647, point[key])
+
+    if DATA["ground"]:
+        size = DATA["groundSize"]
+        mesh = bpy.data.meshes.new("Solved Ground Plane")
+        mesh.from_pydata([(-size, -size, 0), (size, -size, 0),
+                          (size, size, 0), (-size, size, 0)], [], [(0, 1, 2, 3)])
+        mesh.update()
+        ground = bpy.data.objects.new("Solved Ground Plane", mesh)
+        collection.objects.link(ground)
+        ground.display_type = 'WIRE'
+        ground.hide_render = True
+    for marker in DATA["markers"]:
+        scene.timeline_markers.new(marker["name"], frame=marker["frame"])
+
+    _interpolation(camera)
+    _interpolation(camera_data)
+    metadata = bpy.data.texts.new("EffectCraft Tracking Metadata.json")
+    metadata.write(json.dumps(DATA, ensure_ascii=False, indent=2))
+    scene["effectcraft_metadata_text"] = metadata.name
+    camera_data["effectcraft_average_error_pixels"] = DATA["solve"]["averageError"]
+    camera_data["effectcraft_solve_method"] = DATA["solve"]["methodUsed"]
+    camera_data["effectcraft_focus_source"] = "See warnings in " + metadata.name
+    distortion = DATA["solve"].get("distortion")
+    if distortion:
+        for key in ("k1", "k2", "radius"):
+            camera_data["effectcraft_distortion_" + key] = distortion[key]
+    if bpy.context.window is not None:
+        bpy.context.window.scene = scene
+        for area in bpy.context.window.screen.areas:
+            if area.type == 'VIEW_3D':
+                area.spaces.active.region_3d.view_perspective = 'CAMERA'
+    scene.frame_set(scene.frame_start)
+    for warning in DATA["warnings"]:
+        print("EffectCraft: " + warning)
+    print("EffectCraft: imported", len(DATA["frames"]), "baked camera frames into", scene.name)
+    return scene
+
+
+if __name__ == "__main__":
+    EFFECTCRAFT_SCENE = import_scene()

crates/engine/src/cmd/camera_cmds.rs

@@ -42,11 +42,25 @@ pub fn specs() -> Vec<CommandSpec> {
             create_from_solve
         ),
         cmd!("camera.create", "Create Camera", [], None, "{layer?, effect?}", has_comp, |s, p| create_from_solve(s, &with_kind(p, "camera"))),
+        cmd!(
+            "camera.exportBlender",
+            "Export Scene to Blender...",
+            [],
+            None,
+            "{path: .py, comp?, layer?, effect?, sensorWidth?: mm (default 36), unitScale?: Blender units per comp pixel (default 0.01), startFrame?: positive integer (default 1), includePoints?: true}",
+            has_comp,
+            export_blender
+        ),
         cmd!("camera.setGroundPlane", "Set Ground Plane and Origin", [], None, "{points?: [id] (default: selected), layer?, effect?}", has_comp, set_ground),
         cmd!("camera.deletePoints", "Delete Selected Points", [], None, "{points?: [id] (default: selected), layer?, effect?, wait?}", has_comp, delete_points),
     ]
 }
 
+fn export_blender(s: &mut Session, p: &Value) -> Result<Value> {
+    let (cid, lid, uid) = ct_p(s, p, "camera.exportBlender")?;
+    super::blender::export(s, p, cid, lid, uid)
+}
+
 fn with_kind(p: &Value, kind: &str) -> Value {
     let mut q = p.clone();
     if !q.is_object() {

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

@@ -1,11 +1,11 @@
-//! Composition menu, part two: crop to region of interest / layer bounds, Save Frame As ▸ File,
-//! Copy Frame to Clipboard, Responsive Design — Time.
+//! Composition menu, part two: crop to region of interest / layer bounds, Scale Composition, Save
+//! Frame As ▸ File, Copy Frame to Clipboard, Responsive Design — Time.
 
 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);
             }
@@ -71,6 +71,164 @@ fn crop_to_layers(s: &mut Session, p: &Value) -> Result<Value> {
     crop(s, cid, [x0, y0, b[2].ceil() - x0, b[3].ceil() - y0], "Crop Comp to Selected Layer(s) Bounds")
 }
 
+/// Multiply a property's value, every key, its spatial tangents and its speeds by `f`.
+fn scale_prop(pr: &mut effectcraft_project::Property, f: f64) {
+    use effectcraft_keyframe::Value as KV;
+    let mul = |v: &KV| match v {
+        KV::Scalar(x) => KV::Scalar(x * f),
+        KV::Vec2(a) => KV::Vec2(a.map(|x| x * f)),
+        KV::Vec3(a) => KV::Vec3(a.map(|x| x * f)),
+        other => other.clone(),
+    };
+    pr.value = mul(&pr.value);
+    for k in &mut pr.keys {
+        k.value = mul(&k.value);
+        k.spatial_in = k.spatial_in.map(|x| x * f);
+        k.spatial_out = k.spatial_out.map(|x| x * f);
+        for e in k.in_ease.iter_mut().chain(&mut k.out_ease) {
+            e.speed *= f;
+        }
+    }
+}
+
+/// Multiply only the Z of a 3D value (and of its keys and spatial tangents) by `f`. Speeds follow:
+/// a spatial side's speed by how much the path's direction there stretches, so the ease keeps
+/// its shape; a per-dimension one (Scale) by `f` for Z only.
+fn scale_prop_z(pr: &mut effectcraft_project::Property, f: f64) {
+    use effectcraft_keyframe::Value as KV;
+    let stretch = |v: [f64; 3]| {
+        let n = v[0].hypot(v[1]).hypot(v[2]);
+        if n > 1e-12 && n.is_finite() { v[0].hypot(v[1]).hypot(v[2] * f) / n } else { 1.0 }
+    };
+    let pos = |k: &effectcraft_project::Keyframe| k.value.as_vec3();
+    let sub = |a: [f64; 3], b: [f64; 3]| [a[0] - b[0], a[1] - b[1], a[2] - b[2]];
+    let is_zero = |v: [f64; 3]| v.iter().all(|x| x.abs() <= 1e-12);
+    // Read every side's direction before anything changes (auto tangents come from the neighbours).
+    let sides: Vec<(f64, f64)> = (0..pr.keys.len())
+        .map(|i| {
+            let (tin, tout) = effectcraft_keyframe::spatial_tangents(&pr.keys, i);
+            let here = pr.keys.get(i).map(pos).unwrap_or_default();
+            let chord = |j: Option<usize>| j.and_then(|j| pr.keys.get(j)).map(|k| sub(pos(k), here)).unwrap_or_default();
+            let tin = if is_zero(tin) { chord(i.checked_sub(1)) } else { tin };
+            let tout = if is_zero(tout) { chord(Some(i + 1)) } else { tout };
+            (stretch(tin), stretch(tout))
+        })
+        .collect();
+    let spatial = pr.spatial;
+    let mul = |v: &mut KV| {
+        if let KV::Vec3(a) = v {
+            a[2] *= f;
+        }
+    };
+    mul(&mut pr.value);
+    for (k, (s_in, s_out)) in pr.keys.iter_mut().zip(sides) {
+        mul(&mut k.value);
+        k.spatial_in[2] *= f;
+        k.spatial_out[2] *= f;
+        if spatial {
+            k.in_ease.iter_mut().for_each(|e| e.speed *= s_in);
+            k.out_ease.iter_mut().for_each(|e| e.speed *= s_out);
+        } else {
+            // A shorter list lends its first ease to Z (`effective_ease`): give Z its own.
+            for list in [&mut k.in_ease, &mut k.out_ease] {
+                if let Some(&first) = list.first() {
+                    list.resize(list.len().max(3), first);
+                }
+                if let Some(e) = list.get_mut(2) {
+                    e.speed *= f;
+                }
+            }
+        }
+    }
+}
+
+/// Scale Composition (After Effects ships it as File ▸ Scripts ▸ Scale Composition.jsx): the comp
+/// and its contents grow or shrink by one factor, keys included, in one undo step. Layers whose
+/// parent has a Scale follow that parent; everything else scales its Position (and Point of
+/// Interest) and Scale. Anchor Point, masks, shapes and effects live in layer space and follow the
+/// layer's Scale. Cameras scale their Zoom so 3D layers keep their place in the frame; a 2D parent
+/// carries no depth, so its 3D children scale their Z themselves.
+fn scale_comp(s: &mut Session, p: &Value) -> Result<Value> {
+    const C: &str = "comp.scale";
+    let cid = comp_id(s, p)?;
+    let comp = s.project.comp(cid).ok_or(EngineError::NoComp)?;
+    let (ow, oh) = (f64::from(comp.width), f64::from(comp.height));
+    // The three are alternatives: with two, one would be ignored without a word.
+    if ["factor", "width", "height"].iter().filter(|k| f_p(p, k).is_some()).count() > 1 {
+        return Err(bad(C, "pass only one of `factor`, `width` or `height`"));
+    }
+    let f = match (f_p(p, "factor"), f_p(p, "width"), f_p(p, "height")) {
+        (Some(f), ..) => f,
+        (None, Some(w), _) => w / ow,
+        (None, None, Some(h)) => h / oh,
+        _ => return Err(bad(C, "pass `factor`, `width` or `height`")),
+    };
+    let (w, h) = ((ow * f).round(), (oh * f).round());
+    let max = f64::from(effectcraft_project::limits::MAX_SIZE);
+    if !f.is_finite() || f <= 0.0 || !(4.0..=max).contains(&w) || !(4.0..=max).contains(&h) {
+        return Err(bad(C, format!("the composition would be {w}×{h}: width and height run from 4 to 30,000 px")));
+    }
+    let (w, h) = (w as u32, h as u32);
+    let active = s.active_comp_id() == Some(cid);
+    s.edit("Scale Composition", None, |proj, st| {
+        let c = proj.comp_mut(cid).ok_or(EngineError::NoComp)?;
+        // An ancestor's Scale carries its descendants (X and Y only when that ancestor is 2D),
+        // through cameras and lights too: the renderer applies every ancestor's transform.
+        let chain: std::collections::HashMap<_, _> =
+            c.layers.iter().map(|l| (l.id, (l.transform().is_some_and(|tr| tr.get("scale").is_some()), l.is_3d(), l.parent))).collect();
+        // (X and Y carried, Z carried); bounded, as parent chains in a file can loop.
+        let carried = |mut cur: Option<effectcraft_project::LayerId>| {
+            let (mut xy, mut z) = (false, false);
+            for _ in 0..64 {
+                let Some(&(has_scale, three_d, up)) = cur.and_then(|id| chain.get(&id)) else { break };
+                xy |= has_scale;
+                z |= has_scale && three_d;
+                cur = up;
+            }
+            (xy, z)
+        };
+        for l in &mut c.layers {
+            let (xy_carried, z_carried) = carried(l.parent);
+            let three_d = l.is_3d();
+            let Some(tr) = l.transform_mut() else { continue };
+            if !xy_carried {
+                for name in ["position", "positionX", "positionY", "positionZ", "poi", "scale"] {
+                    if let Some(pr) = tr.get_mut(name) {
+                        scale_prop(pr, f);
+                    }
+                }
+            } else if three_d && !z_carried {
+                if let Some(pr) = tr.get_mut("positionZ") {
+                    scale_prop(pr, f);
+                }
+                for name in ["position", "poi", "scale"] {
+                    if let Some(pr) = tr.get_mut(name) {
+                        scale_prop_z(pr, f);
+                    }
+                }
+            }
+            if let Some(cam) = l.props.sub_mut("cameraOptions") {
+                for name in ["zoom", "focusDistance", "aperture"] {
+                    if let Some(pr) = cam.get_mut(name) {
+                        scale_prop(pr, f);
+                    }
+                }
+            }
+        }
+        // Percentage guides keep their percent.
+        for g in c.guides.iter_mut().filter(|g| !g.percent) {
+            g.position *= f;
+        }
+        c.width = w;
+        c.height = h;
+        if active && let Some(r) = &mut st.region_of_interest {
+            *r = r.map(|v| v * f);
+        }
+        Ok(())
+    })?;
+    Ok(json!({"width": w, "height": h, "factor": f}))
+}
+
 /// Encode straight 8-bit RGBA as PNG.
 pub(crate) fn encode_png(rgba: &[u8], w: u32, h: u32) -> std::result::Result<Vec<u8>, String> {
     use image::ImageEncoder;
@@ -82,7 +240,7 @@ 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)?;
@@ -91,10 +249,16 @@ 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() {
-        it.output.output = "[compName]_frame.[fileExtension]".into();
+    } else {
+        if !it.output.format.is_sequence() {
+            it.output.output = "[compName]_frame.[fileExtension]".into();
+        }
+        s.avoid_sources(&mut it);
     }
     let id = s.edit("Save Frame As", None, |proj, _| {
         it.id = proj.render_queue.iter().map(|i| i.id).max().unwrap_or(0) + 1;
@@ -107,7 +271,7 @@ 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 +281,7 @@ 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}"));
@@ -230,12 +394,21 @@ pub fn specs() -> Vec<CommandSpec> {
     vec![
         cmd!("comp.cropToRegionOfInterest", "Crop Comp to Region of Interest", ["Composition"], None, "{comp?}", has_roi, crop_to_roi),
         cmd!("comp.cropToLayerBounds", "Crop Comp to Selected Layer(s) Bounds", ["Composition"], None, "{layers?}", has_layers, crop_to_layers),
+        cmd!(
+            "comp.scale",
+            "Scale Composition",
+            [],
+            None,
+            "{comp?, factor? (2 = twice the size) | width? | height? (the other side keeps the aspect ratio)}",
+            has_comp,
+            scale_comp
+        ),
         cmd!(
             "comp.saveFrameAs",
             "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/content_fill.rs

@@ -170,6 +170,21 @@ pub struct FillPlan {
     pub dir: String,
 }
 
+/// The fill holds every frame as float RGBA (16 bytes a pixel), its hole mask (1) and the filled
+/// copy (16) until it finishes (#1789): when even that is more than `available`, the error to
+/// report up front, instead of running out of memory partway through.
+fn memory_shortfall(frames: usize, w: u32, h: u32, available: u64) -> Option<String> {
+    let need = (frames as u64).saturating_mul(u64::from(w)).saturating_mul(u64::from(h)).saturating_mul(33);
+    (need > available).then(|| {
+        let gb = |b: u64| b as f64 / 1e9;
+        format!(
+            "Content-Aware Fill of {frames} frames at {w}×{h} needs at least {:.1} GB of memory, and {:.1} GB is free: fill a shorter range (set the work area and choose Work Area) or close other applications",
+            gb(need),
+            gb(available)
+        )
+    })
+}
+
 /// Run a fill: the layer's frames (rendered in passes with a job worker's GPU), the fill, the
 /// PNG sequence written into `plan.dir` (`Services::store_file`). Returns the files.
 #[allow(clippy::too_many_arguments)]
@@ -275,6 +290,9 @@ fn generate(s: &mut Session, p: &Value) -> Result<Value> {
     }
     let (fa, fb) = (fr.frame_at(fr.snap_nearest(a)), fr.frame_at(b - Tick(1)));
     let times: Vec<Tick> = (fa..=fb).map(|f| fr.tick_of(f)).collect();
+    if let Some(e) = crate::sysinfo::memory().and_then(|m| memory_shortfall(times.len(), w, h, m.available)) {
+        return Err(bad(c, e));
+    }
     let opts = FillOpts {
         method: FillMethod::from_name(&st.method).unwrap_or_default(),
         lighting: lighting(&st.lighting_correction).unwrap_or(0.0),
@@ -424,3 +442,18 @@ pub fn specs() -> Vec<CommandSpec> {
         },
     ]
 }
+
+#[cfg(test)]
+mod tests {
+    use super::memory_shortfall;
+
+    /// #1789: 10 s of 1080p30 (300 frames) needs at least 20 GB, which 4 GB free can't hold.
+    #[test]
+    fn a_fill_that_cannot_fit_in_memory_is_refused_up_front() {
+        let e = memory_shortfall(300, 1920, 1080, 4_000_000_000).expect("refused");
+        assert!(e.contains("300 frames") && e.contains("Work Area"), "{e}");
+        assert_eq!(memory_shortfall(30, 1920, 1080, 4_000_000_000), None, "a second of it fits");
+        // Hostile sizes saturate instead of overflowing.
+        assert!(memory_shortfall(usize::MAX, u32::MAX, u32::MAX, u64::MAX - 1).is_some());
+    }
+}

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 }));
     }
@@ -133,12 +133,11 @@ fn duplicate(s: &mut Session, p: &Value) -> Result<Value> {
             return super::prop_groups::duplicate_contents(s, &items);
         }
     }
-    // A deselected layer never keeps an open text edit: the copies take the selection, so commit
-    // an open edit first, exactly as `text.endEdit` (typed text kept, an empty Type-tool layer
-    // discarded) and as Deselect All does — one call on the command path so every route (menu,
-    // shortcut, palette, MCP, script) ends the edit and leaves the same final state. Unnamed, the
-    // target is the edited layer even when an engine route selected another one meanwhile; it is
-    // read before the commit, which may discard an empty Type-tool layer and leave nothing to copy.
+    // A deselected layer never keeps an open text edit (#2226): the copies take the selection, so
+    // commit an open edit first, exactly as `text.endEdit` and Deselect All do — one call on the
+    // command path so every route (menu, shortcut, palette, MCP, script) ends the edit and leaves
+    // the same final state. Unnamed, the target is the edited layer even when an engine route
+    // selected another one meanwhile.
     let edited = s.state.text_edit.as_ref().map(|e| e.layer);
     super::text_edit::end_edit(s, &Value::Null)?;
     let (cid, ids) = match edited {
@@ -288,6 +287,7 @@ fn clear_clipboards(s: &mut Session) {
     s.state.contents_clipboard.clear();
     s.state.link_clipboard = None;
     s.state.value_clipboard.clear();
+    s.state.keyframe_text = None;
     s.state.clip_is_keys = false;
 }
 
@@ -354,10 +354,12 @@ fn copy_properties(s: &mut Session) -> Result<Option<Value>> {
     }
     let mut keys = s.state.selected_keys.clone();
     let mut values = vec![];
+    let mut statics = vec![];
     for (lid, uid) in &leaves {
         let Some(l) = comp.layer(*lid) else { continue };
         let Some(pr) = l.props.find(*uid) else { continue };
         if pr.keys.is_empty() {
+            statics.push((*lid, *uid));
             if let Some(path) = l.props.match_path_of(*uid)
                 && !values.iter().any(|(p, _)| *p == path)
             {
@@ -367,6 +369,7 @@ fn copy_properties(s: &mut Session) -> Result<Option<Value>> {
             keys.extend(pr.keys.iter().map(|k| KeyRef { layer: *lid, prop: *uid, time: k.time }));
         }
     }
+    let text = crate::keyframe_text::text(&s.project, comp, &keys, &statics);
     clear_clipboards(s);
     let mut n = 0;
     if !keys.is_empty() {
@@ -375,6 +378,7 @@ fn copy_properties(s: &mut Session) -> Result<Option<Value>> {
         s.state.selected_keys = selected;
         n = r?.as_u64().unwrap_or(0);
     }
+    s.state.keyframe_text = text;
     let v = values.len();
     s.state.value_clipboard = values;
     // Keys alone answer as `keys.copy` does (their count).
@@ -700,7 +704,7 @@ 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());
@@ -700,7 +745,7 @@ fn effects_p(s: &Session, p: &Value, cmd: &str) -> Result<Vec<(LayerId, Uid)>> {
     Ok(sel)
 }
 
-fn effect_time_error(cmd: &str) -> EngineError {
+pub(crate) fn effect_time_error(cmd: &str) -> EngineError {
     bad(cmd, "an effect keyframe converts outside the supported time range")
 }
 
@@ -736,7 +781,7 @@ fn effect_time(layer: &Layer, time: Tick, to_comp: bool, cmd: &str) -> Result<Ti
 
 /// Change the key time coordinate system throughout an effect, including nested controls.
 /// Ease speeds are per second in that coordinate system; reversed time swaps the key sides.
-fn retime_effect(group: &mut PropGroup, scale: f64, cmd: &str, mut time: impl FnMut(Tick) -> Result<Tick>) -> Result<()> {
+pub(crate) fn retime_effect(group: &mut PropGroup, scale: f64, cmd: &str, mut time: impl FnMut(Tick) -> Result<Tick>) -> Result<()> {
     let mut result = Ok(());
     group.walk_mut(&mut |pr| {
         if result.is_err() {
@@ -804,6 +849,7 @@ fn copy(s: &mut Session, p: &Value) -> Result<Value> {
     }
     s.state.clipboard.clear();
     s.state.key_clipboard.clear();
+    s.state.keyframe_text = None;
     s.state.contents_clipboard.clear();
     s.state.link_clipboard = None;
     s.state.clip_is_keys = false;
@@ -954,8 +1000,7 @@ fn list(_: &mut Session, p: &Value) -> Result<Value> {
                 let mut out = json!({"id": p.id, "name": p.name, "type": p.default.kind_name(), "default": p.default.to_json()});
                 match &p.ui {
                     effectcraft_project::ParamUi::Popup { options } => {
-                        // Engine/MCP popup values are zero-based; JSX exposes one-based values.
-                        out["options"] = json!(options.iter().enumerate().map(|(value, label)| json!({"value": value, "label": label})).collect::<Vec<_>>());
+                        out["options"] = super::popup_options(options);
                     }
                     effectcraft_project::ParamUi::Slider { min, max, slider_min, slider_max, decimals } => {
                         out["min"] = json!(min);

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?, frameRate?: fps|\"file\", alpha?: straight|premultiplied|ignore|guess, guessAlpha?, matteColor?, 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
         ),
@@ -1084,7 +1266,7 @@ pub fn specs() -> Vec<CommandSpec> {
             "Apply Interpretation",
             ["File", "Interpret Footage"],
             Some("Cmd+Alt+V"),
-            "{items?}",
+            "{items?|item?}",
             has_interpretation,
             apply_interpretation
         ),
@@ -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
         ),
@@ -1115,7 +1297,7 @@ pub fn specs() -> Vec<CommandSpec> {
             has_footage_selection,
             replace_with_solid
         ),
-        cmd!("file.reloadFootage", "Reload Footage", ["File"], Some("Cmd+Alt+L"), "{items?}", has_footage_selection, reload),
+        cmd!("file.reloadFootage", "Reload Footage", ["File"], Some("Cmd+Alt+L"), "{items?|item?}", has_footage_selection, reload),
         cmd!("file.revealInFinder", "Reveal in Finder", ["File"], None, "{item?}", has_footage_selection, reveal_in_finder),
     ]
 }

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") {
@@ -207,10 +213,7 @@ fn info(s: &mut Session, _: &Value) -> Result<Value> {
     let item = s.project.item(v.item);
     let name = item.map(|i| i.name.clone()).unwrap_or_default();
     let frame = fr.frame_at(v.time);
-    let problem = match item.map(|i| &i.kind) {
-        Some(ItemKind::Footage(f)) => s.footage.problem(f),
-        _ => None,
-    };
+    let problem = item.and_then(|i| s.footage.item_problem(i));
     Ok(
         json!({"item": v.item.0, "name": name, "time": v.time.seconds(), "frame": frame, "timecode": timecode(item, fr, frame), "in": v.in_point.map(|t| t.seconds()), "out": v.out_point.map(|t| t.seconds()), "duration": dur.map(|d| d.seconds()), "frameRate": fr.as_f64(), "problem": problem}),
     )

crates/engine/src/cmd/layer.rs

@@ -49,7 +49,7 @@ 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
         ),
@@ -122,7 +122,7 @@ 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
         ),
@@ -184,7 +184,7 @@ 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
         ),
@@ -193,7 +193,7 @@ 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/link.rs

@@ -102,11 +102,39 @@ fn quote(s: &str) -> String {
 
 /// The AE expression reference to property `uid` of `target` as seen from a property of `from`.
 pub(crate) fn reference(comp: &Comp, from: &Layer, target: &Layer, uid: Uid, compact: bool) -> Option<String> {
+    reference_with(comp, from, target, uid, compact, false)
+}
+
+/// [`reference`], with the properties inside an effect selected by their index (`by_index`, an
+/// Alt pick whip in After Effects): `effect("Color Control")(1)` rather than `("Color")`. The
+/// effect keeps its name. An index is the property's place among its group's children, as an
+/// expression's `(1)` reads it: it follows a renamed parameter, not one moved to another place.
+pub(crate) fn reference_with(comp: &Comp, from: &Layer, target: &Layer, uid: Uid, compact: bool, by_index: bool) -> Option<String> {
     let chain = target.props.node_chain(uid)?;
+    // Each node's one-based index among its group's children, and whether it lies inside an
+    // effect (below the effect itself): those are selected by index with `by_index`.
+    let mut parent = &target.props;
+    let mut depth_in_effects: Option<usize> = None;
+    let mut by_number: Vec<Option<usize>> = vec![];
+    for n in &chain {
+        let at = parent.children.iter().position(|c| c.uid() == n.uid()).map(|i| i + 1);
+        by_number.push(at.filter(|_| by_index && depth_in_effects.is_some_and(|d| d >= 1)));
+        depth_in_effects = match depth_in_effects {
+            Some(d) => Some(d + 1),
+            None => (n.match_id() == "effects").then_some(0),
+        };
+        if let Node::Group(g) = n {
+            parent = g;
+        }
+    }
+    let selector = |i: usize, label: &str| match by_number.get(i).copied().flatten() {
+        Some(at) => format!("({at})"),
+        None => format!("({})", quote(label)),
+    };
     let mut parts: Vec<String> = vec![];
     let mut pending: Option<&str> = None;
     let mut in_effect = false;
-    for n in chain {
+    for (i, n) in chain.iter().copied().enumerate() {
         if let Some(f) = pending.take() {
             parts.push(format!("{f}({})", quote(n.name())));
             in_effect |= f == "effect";
@@ -119,7 +147,7 @@ pub(crate) fn reference(comp: &Comp, from: &Layer, target: &Layer, uid: Uid, com
             (Node::Group(_), "transform") if !in_effect => parts.push("transform".into()),
             (Node::Group(_), "text") if !in_effect => parts.push("text".into()),
             (Node::Prop(_), "sourceText") => parts.push("sourceText".into()),
-            _ if in_effect => parts.push(format!("({})", quote(n.name()))),
+            _ if in_effect => parts.push(selector(i, n.name())),
             _ => parts.push(camel(n.name())),
         }
     }
@@ -127,10 +155,9 @@ pub(crate) fn reference(comp: &Comp, from: &Layer, target: &Layer, uid: Uid, com
     let _ = comp;
     if !compact {
         // Match names: language-independent, like After Effects with Compact English off.
-        let chain = target.props.node_chain(uid)?;
         let mut out = if from.id == target.id { "thisLayer".to_string() } else { format!("thisComp.layer({})", quote(&target.name)) };
-        for n in chain {
-            out.push_str(&format!("({})", quote(n.match_id())));
+        for (i, n) in chain.iter().copied().enumerate() {
+            out.push_str(&selector(i, n.match_id()));
         }
         return Some(out);
     }
@@ -161,7 +188,9 @@ fn pick_whip(s: &mut Session, p: &Value) -> Result<Value> {
     let comp = s.project.comp(cid).ok_or(EngineError::NoComp)?;
     let from = comp.layer(lid).ok_or(EngineError::NoComp)?;
     let target = comp.layer(tl).ok_or(EngineError::NoComp)?;
-    let r = reference(comp, from, target, tu, s.prefs.general.expression_pick_whip_compact).ok_or_else(|| bad("prop.pickWhip", "no such target property"))?;
+    let by_index = b_p(p, "byIndex").unwrap_or(false);
+    let r = reference_with(comp, from, target, tu, s.prefs.general.expression_pick_whip_compact, by_index)
+        .ok_or_else(|| bad("prop.pickWhip", "no such target property"))?;
     let (me, them) = (from.props.find(uid).ok_or(EngineError::NoComp)?, target.props.find(tu).ok_or(EngineError::NoComp)?);
     let (dm, dt) = (dims(from, me), dims(target, them));
     // Dropped on one of the target's values: that dimension (`position[0]`), as in After Effects.
@@ -206,7 +235,7 @@ pub fn specs() -> Vec<CommandSpec> {
             "Pick Whip (Link Property)",
             [],
             None,
-            "{layer?, path|prop, target: {layer, path|prop, dimension?}, expression?, range?: [start, end]} → sets an AE reference expression (`dimension`: one of the target's values, `position[0]`; with `expression`: inserts it there, replacing the characters in `range`, default the end)",
+            "{layer?, path|prop, target: {layer, path|prop, dimension?}, expression?, range?: [start, end], byIndex?: bool} → sets an AE reference expression (`dimension`: one of the target's values, `position[0]`; with `expression`: inserts it there, replacing the characters in `range`, default the end; `byIndex`: an effect's properties by their index, `effect(\"Color Control\")(1)`, as an Alt pick whip does)",
             has_layers,
             pick_whip
         ),

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/mask_interp.rs

@@ -289,6 +289,7 @@ fn extract_face(s: &mut Session, p: &Value) -> Result<Value> {
         clip.push(crate::KeyClip { layer: lid, path, keys });
     }
     s.state.key_clipboard = clip;
+    s.state.keyframe_text = None;
     s.state.clip_is_keys = true;
     // The same data as text (tab-separated, one row per frame) for other applications.
     let mut text = String::from("EffectCraft Face Measurements\n\nFrame\tTime");

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/params.rs

@@ -58,6 +58,12 @@ pub(crate) fn selected_leaf_props(s: &Session) -> Vec<(LayerId, effectcraft_proj
     out
 }
 
+/// A popup's `[{value, label}]`, as `effect.list`, `prop.get` and `layer.tree` report it.
+/// Engine/MCP popup values are zero-based; JSX exposes one-based values.
+pub(crate) fn popup_options(options: &[String]) -> Value {
+    serde_json::json!(options.iter().enumerate().map(|(value, label)| serde_json::json!({"value": value, "label": label})).collect::<Vec<_>>())
+}
+
 // ---------- params ----------
 
 pub(crate) fn bad(cmd: &str, msg: impl Into<String>) -> EngineError {

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

@@ -5,10 +5,11 @@
 use effectcraft_keyframe::{ShapePath, Value as KV};
 use effectcraft_project::build::{self, Ids};
 use effectcraft_project::{FeatherFalloff, GroupKind, ItemId, LayerId, LayerSource, MaskMotionBlur, Node, PropGroup, Uid};
+use effectcraft_render::EvalCtx;
 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
@@ -111,18 +112,30 @@ fn roto_bezier(s: &mut Session, p: &Value) -> Result<Value> {
 /// The parametric shape paths that Convert To Bezier Path replaces with an editable path.
 const PARAMETRIC: [&str; 3] = ["rect", "ellipse", "star"];
 
-/// The path a parametric shape group draws, in the group's own space, read at `lt`. This is the
-/// geometry the renderer builds from the same values (`render::shapes::collect`), so the converted
-/// path is the shape that was on screen rather than an approximation of it; the defaults match
-/// that code for a property a group doesn't carry (a polygon has no inner radius or roundness).
-fn parametric_path(g: &PropGroup, lt: effectcraft_time::Tick) -> Option<ShapePath> {
-    let f = |id: &str, d: f64| g.prop(id).map_or(d, |pr| pr.value_at(lt).as_f64());
-    let v2 = |id: &str, d: [f64; 2]| g.prop(id).map_or(d, |pr| pr.value_at(lt).as_vec2());
+/// The path a parametric shape group draws, in the group's own space. This is the geometry the
+/// renderer builds from the same values (`render::shapes::collect`), expressions included, so the
+/// converted path is the shape that was on screen rather than an approximation of it; the defaults
+/// match that code for a property a group doesn't carry (a polygon has no inner radius or
+/// roundness).
+fn parametric_path(ctx: &EvalCtx, layer: &effectcraft_project::Layer, g: &PropGroup) -> Option<ShapePath> {
+    let f = |id: &str, d: f64| ctx.f(layer, g, id, d);
+    let v2 = |id: &str, d: [f64; 2]| ctx.v2(layer, g, id, d);
     let path = match g.match_id.as_str() {
-        "rect" => effectcraft_path::rect(v2("size", [100.0; 2]), v2("position", [0.0; 2]), f("roundness", 0.0)),
+        "rect" => {
+            let (size, pos) = (v2("size", [100.0; 2]), v2("position", [0.0; 2]));
+            if ctx.b(layer, g, "perCorner") {
+                effectcraft_path::rect_radii(
+                    size,
+                    pos,
+                    [f("topLeftRoundness", 0.0), f("topRightRoundness", 0.0), f("bottomRightRoundness", 0.0), f("bottomLeftRoundness", 0.0)],
+                )
+            } else {
+                effectcraft_path::rect(size, pos, f("roundness", 0.0))
+            }
+        }
         "ellipse" => effectcraft_path::ellipse(v2("size", [100.0; 2]), v2("position", [0.0; 2])),
         "star" => effectcraft_path::polystar(effectcraft_path::Polystar {
-            star: g.prop("type").map_or(0, |pr| pr.value_at(lt).as_enum()) == 0,
+            star: ctx.e(layer, g, "type") == 0,
             points: f("points", 5.0),
             pos: v2("position", [0.0; 2]),
             rotation: f("rotation", 0.0),
@@ -160,28 +173,38 @@ fn convert_to_bezier(s: &mut Session, p: &Value) -> Result<Value> {
     }
     let t = s.time();
     let n = shapes.len();
+    // Read the geometry before editing, with the same expression-aware context the renderer
+    // uses: an expression-driven corner radius, size or position must convert to what is on
+    // screen, not to the property's underlying value.
+    let prepared = {
+        let comp = s.project.comp(cid).ok_or(EngineError::NoComp)?;
+        let ctx = EvalCtx { expr: s.expr.as_deref(), ..EvalCtx::new(&s.project, cid, comp, t) };
+        let mut prepared = Vec::new();
+        for (lid, uid) in &shapes {
+            let Some(l) = comp.layer(*lid) else { continue };
+            let Some(old) = l.props.sub("contents").and_then(|c| c.find_group(*uid)) else { continue };
+            let Some(path) = parametric_path(&ctx, l, old) else { continue };
+            // Path Direction is the shape's own, not a default: reversing is a separate command.
+            prepared.push((*lid, *uid, path, ctx.e(l, old, "direction"), old.enabled));
+        }
+        prepared
+    };
     let made = s.edit("Convert To Bezier Path", None, |proj, st| {
         let mut next = proj.next_id;
         let mut made = Vec::new();
-        for (lid, uid) in &shapes {
-            let l = layer_mut(proj, cid, *lid)?;
-            let lt = l.layer_time(t);
+        for (lid, uid, path, direction, enabled) in prepared {
+            let l = layer_mut(proj, cid, lid)?;
             let contents = l.props.sub_mut("contents").ok_or_else(|| bad("path.convertToBezier", "not a shape layer"))?;
-            let Some(old) = contents.find_group(*uid) else { continue };
-            let Some(path) = parametric_path(old, lt) else { continue };
-            // Path Direction is the shape's own, not a default: reversing is a separate command.
-            let direction = old.prop("direction").map_or(0, |pr| pr.value_at(lt).as_enum());
-            let enabled = old.enabled;
             let mut g = build::shape_path(&mut Ids(&mut next), path);
             if let Some(pr) = g.prop_mut("direction") {
                 pr.value = KV::Enum(direction);
             }
             g.enabled = enabled;
             let new_uid = g.uid;
-            let parent = contents.parent_of_mut(*uid).ok_or_else(|| bad("path.convertToBezier", "no such shape item"))?;
-            let Some(at) = parent.children.iter().position(|c| c.uid() == *uid) else { continue };
+            let parent = contents.parent_of_mut(uid).ok_or_else(|| bad("path.convertToBezier", "no such shape item"))?;
+            let Some(at) = parent.children.iter().position(|c| c.uid() == uid) else { continue };
             parent.children[at] = Node::Group(g);
-            made.push((*lid, new_uid));
+            made.push((lid, new_uid));
         }
         proj.next_id = next;
         // The new paths are what is selected, so the vertices can be edited straight away.
@@ -308,7 +331,7 @@ 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 +383,7 @@ 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 +565,7 @@ 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

@@ -48,7 +48,6 @@ fn with_prop<T>(
     let t = s.time_of(cid);
     let linear = s.prefs.general.default_spatial_linear;
     s.edit(label, merge, |proj, state| {
-        let mut next = proj.next_id;
         let l = layer_mut(proj, cid, lid)?;
         let lt = l.layer_time(t);
         let pr = l.props.find_mut(uid).ok_or_else(|| bad("prop", "property vanished"))?;
@@ -64,17 +63,37 @@ fn with_prop<T>(
             }
         }
         if pr.match_id == "type" {
-            let removed = sync_polystar_type(l, uid, lt, &mut next)?;
-            if !removed.is_empty() {
-                state.selected_props.retain(|(layer, prop)| *layer != lid || !removed.contains(prop));
-                state.selected_keys.retain(|key| key.layer != lid || !removed.contains(&key.prop));
-            }
+            sync_polystar_property(proj, state, cid, lid, uid, t)?;
         }
-        proj.next_id = next;
         Ok(r)
     })
 }
 
+/// Keep Polystar controls and their selection references in the property's edit transaction.
+pub(super) fn sync_polystar_property(
+    proj: &mut effectcraft_project::Project,
+    state: &mut crate::EditorState,
+    cid: ItemId,
+    lid: LayerId,
+    uid: Uid,
+    time: Tick,
+) -> Result<()> {
+    let mut next = proj.next_id;
+    let layer = layer_mut(proj, cid, lid)?;
+    let removed = sync_polystar_type(layer, uid, layer.layer_time(time), &mut next)?;
+    if !removed.is_empty() {
+        if state.active_comp == Some(cid) {
+            state.selected_props.retain(|(layer, prop)| *layer != lid || !removed.contains(prop));
+            state.selected_keys.retain(|key| key.layer != lid || !removed.contains(&key.prop));
+        } else if let Some(selection) = state.comp_selections.get_mut(&cid) {
+            selection.props.retain(|(layer, prop)| *layer != lid || !removed.contains(prop));
+            selection.keys.retain(|key| key.layer != lid || !removed.contains(&key.prop));
+        }
+    }
+    proj.next_id = next;
+    Ok(())
+}
+
 /// A static Polygon has no inner controls; switching to Star creates them in schema order
 /// with AE's switch defaults (#1685). Animated/expression-driven types need the controls at
 /// every time, including when the current value is Polygon.
@@ -491,6 +510,9 @@ fn get(s: &mut Session, p: &Value) -> Result<Value> {
         "time": t.seconds(), "value": raw.to_json(), "animated": !pr.keys.is_empty(),
         "keys": keys, "expression": pr.expr.as_ref().map(|e| e.text.clone()),
     });
+    if let Some(o) = l.popup_options(pr) {
+        out["options"] = super::popup_options(&o);
+    }
     // With an expression, `value` is the keyframed (pre-expression) value; also report what the
     // expression makes of it (what renders), or why it fails. A disabled one renders `value`; one
     // disabled by its syntax error (prop.setExpression) reports that error.
@@ -661,12 +683,21 @@ fn set_expr(s: &mut Session, p: &Value) -> Result<Value> {
             s.project.comp(*cid).and_then(|c| c.layer(*lid).and_then(|l| super::link::reference(c, l, l, *uid, true))).unwrap_or_else(|| "value".into())
         })
         .collect();
-    let results = s.edit("Expression", merge_p(p), |proj, _| {
+    let times: Vec<_> = targets.iter().map(|(cid, _, _)| s.time_of(*cid)).collect();
+    let results = s.edit("Expression", merge_p(p), |proj, state| {
         let mut out = vec![];
-        for ((cid, lid, uid), def) in targets.iter().zip(&defs) {
+        let mut changed_types = vec![];
+        for (((cid, lid, uid), def), time) in targets.iter().zip(&defs).zip(&times) {
             let pr = layer_mut(proj, *cid, *lid)?.props.find_mut(*uid).ok_or_else(|| bad(C, "property vanished"))?;
             apply_expr(pr, &text, enabled, def);
             out.push(json!(pr.expr.as_ref().map(|e| e.text.clone())));
+            if pr.match_id == "type" {
+                changed_types.push((*cid, *lid, *uid, *time));
+            }
+        }
+        // All selected targets must be edited before a Type change can remove inner controls.
+        for (cid, lid, uid, time) in changed_types {
+            sync_polystar_property(proj, state, cid, lid, uid, time)?;
         }
         Ok(out)
     })?;
@@ -1042,9 +1073,11 @@ fn move_keys(s: &mut Session, p: &Value) -> Result<Value> {
 fn delete_keys(s: &mut Session, _: &Value) -> Result<Value> {
     let cid = s.active_comp_id().ok_or(EngineError::NoComp)?;
     let sel = s.state.selected_keys.clone();
+    let time = s.time();
     s.edit("Delete Keyframes", None, |proj, st| {
         let comp = proj.comp_mut(cid).ok_or(EngineError::NoComp)?;
         let mut removed = 0usize;
+        let mut changed = std::collections::BTreeSet::new();
         for k in &sel {
             if let Some(pr) = comp.layer_mut(k.layer).and_then(|l| l.props.find_mut(k.prop))
                 && let Some(i) = key_at(&pr.keys, k.time)
@@ -1054,9 +1087,15 @@ fn delete_keys(s: &mut Session, _: &Value) -> Result<Value> {
                 }
                 pr.keys.remove(i);
                 removed += 1;
+                if pr.match_id == "type" {
+                    changed.insert((k.layer, k.prop));
+                }
             }
         }
         st.selected_keys.clear();
+        for (layer, prop) in changed {
+            sync_polystar_property(proj, st, cid, layer, prop, time)?;
+        }
         // The keys actually removed: a selected key that is gone (or listed twice) isn't counted,
         // so a caller can tell that a delete changed nothing.
         Ok(json!(removed))
@@ -1189,6 +1228,15 @@ 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 +1333,16 @@ 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 +1429,7 @@ 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| {
@@ -190,6 +191,8 @@ fn create_proxy(s: &mut Session, p: &Value) -> Result<Value> {
     it.output.channels = Channels::Rgba;
     if let Some(o) = str_p(p, "path").or(str_p(p, "output")) {
         it.output.output = o.to_string();
+    } else {
+        s.avoid_sources(&mut it);
     }
     it.post_render = PostRenderAction::SetProxy;
     let id = s.edit("Create Proxy", None, |proj, _| {
@@ -229,7 +232,7 @@ pub fn specs() -> Vec<CommandSpec> {
             "Proxy...",
             ["File", "Interpret Footage"],
             None,
-            "{items?|item?, alpha?, matteColor?, invertAlpha?, frameRate?, loop?, pixelAspect?, fields?, colorProfile?, linearLight?}",
+            "{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/query.rs

@@ -46,11 +46,9 @@ fn summary(s: &mut Session, _: &Value) -> Result<Value> {
                 o["layers"] = json!(c.layers.len());
                 o["frameRate"] = json!(c.frame_rate.as_f64());
             }
-            // Footage that shows no picture although its file is there (a codec or profile the
-            // decoders lack): why, so an agent can tell the user.
-            if let ItemKind::Footage(f) = &i.kind
-                && let Some(why) = s.footage.problem(f)
-            {
+            // Footage (or the proxy in use) that shows no picture although its file is there (a
+            // codec or profile the decoders lack): why, so an agent can tell the user.
+            if let Some(why) = s.footage.item_problem(i) {
                 o["problem"] = json!(why);
             }
             o
@@ -129,6 +127,9 @@ fn group_json(g: &PropGroup, path: &str, l: &Layer, t: effectcraft_time::Tick, d
                         if let Some(e) = &p.expr {
                             o["expression"] = json!(e.text);
                         }
+                        if let Some(opts) = l.popup_options(p) {
+                            o["options"] = super::popup_options(&opts);
+                        }
                         o
                     }
                     Node::Group(g) => group_json(g, &cpath, l, t, depth + 1, max_depth),

crates/engine/src/cmd/render_queue.rs

@@ -203,7 +203,7 @@ fn apply_om_template(om: &mut OutputModule, t: &OutputModule) {
 }
 
 /// The `format` parameter's values.
-const FORMATS: &str = "format: h264|hevc|av1|prores|uncompressed|webm|png|jpeg|tiff|exr|gif|wav|aiff";
+const FORMATS: &str = "format: h264|hevc|av1|prores|uncompressed|webm|png|jpeg|tiff|exr|tga|gif|wav|aiff";
 
 /// `channels` (refusing RGBA where the format has no alpha) and `color`/`alphaMode`.
 fn apply_channels_and_alpha(om: &mut OutputModule, p: &Value, cmd: &str) -> Result<()> {
@@ -550,6 +550,9 @@ fn add(s: &mut Session, p: &Value) -> Result<Value> {
         object.remove("template");
     }
     apply_output(&mut it.output, &templates, s.state.region_of_interest, &output_params, "renderQueue.add")?;
+    if str_p(p, "output").or(str_p(p, "path")).is_none() {
+        s.avoid_sources(&mut it);
+    }
     if let Some(l) = enum_p(p, "log", "renderQueue.add", RenderLog::parse, "errorsOnly|plusSettings|plusPerFrameInfo")? {
         it.log = l;
     }
@@ -619,7 +622,7 @@ 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") {
@@ -696,8 +699,18 @@ fn render(s: &mut Session, p: &Value) -> Result<Value> {
     {
         log::warn!("{e}");
     }
+    let queued: std::collections::HashSet<u64> = s.project.render_queue.iter().filter(|i| i.is_queued()).map(|i| i.id).collect();
     let ids = s.start_render(wait).map_err(EngineError::Other)?;
-    let items: Vec<Value> = s.project.render_queue.iter().enumerate().filter(|(_, i)| ids.contains(&i.id)).map(|(k, i)| item_json(s, i, k)).collect();
+    // Source refusals fail before the exporter starts. Report them just like encoding
+    // failures, so CLI/MCP callers do not mistake a partly refused queue for full success.
+    let items: Vec<Value> = s
+        .project
+        .render_queue
+        .iter()
+        .enumerate()
+        .filter(|(_, i)| ids.contains(&i.id) || (queued.contains(&i.id) && matches!(i.status, RenderStatus::Failed(_))))
+        .map(|(k, i)| item_json(s, i, k))
+        .collect();
     Ok(json!({"rendering": s.is_rendering(), "items": items}))
 }
 
@@ -788,6 +801,9 @@ fn pre_render(s: &mut Session, p: &Value) -> Result<Value> {
     it.output = templates.default_output_module(TemplateSlot::PreRender);
     it.output.output = "[compName]_prerender.[fileExtension]".into();
     apply_output(&mut it.output, &templates, s.state.region_of_interest, p, "render.preRender")?;
+    if str_p(p, "output").or(str_p(p, "path")).is_none() {
+        s.avoid_sources(&mut it);
+    }
     it.post_render = PostRenderAction::ImportAndReplace;
     let id = s.edit("Pre-render", None, |proj, _| {
         it.id = proj.render_queue.iter().map(|i| i.id).max().unwrap_or(0) + 1;
@@ -813,6 +829,9 @@ fn save_current_preview(s: &mut Session, p: &Value) -> Result<Value> {
     let mut item = RenderQueueItem::new(0, cid);
     item.output = OutputModule::for_format(format);
     item.output.output = path.clone();
+    if let Some(refusal) = s.check_outputs(&[vec![(item.clone(), path.clone())]]).first() {
+        return Err(EngineError::Other(refusal.reason.clone()));
+    }
     let job = crate::ExportJob {
         project: &s.project,
         footage: s.footage.as_ref(),
@@ -1017,7 +1036,7 @@ pub fn specs() -> Vec<CommandSpec> {
             "Add to Render Queue",
             ["Composition"],
             ["Cmd+M", "Cmd+Shift+/"],
-            "{comp?: id|name, template?: Render Settings template, format?: h264|hevc|av1|prores|uncompressed|webm|png|jpeg|tiff|exr|gif|wav|aiff, output?: path|template, log?: errorsOnly|plusSettings|plusPerFrameInfo, quality?: best|draft|1-100 (jpeg, webm), resolution?: full|half|third|quarter|scale, proxyUse?, effects?, solo?, guideLayers?, colorDepth?, frameBlending?, fieldRender?, pulldown?, motionBlur?, timeSpan?: workArea|comp|custom, start?: s, end?: s, duration?: s, frameRate?: fps|null, skipExisting?: bool, storageOverflow?: bool, channels?: rgb|rgba|alpha, color?, bitrate?: kbps, webmBitrate?, keyframeInterval?, proresProfile?, profile?, level?, rateControl?, webmCodec?, audioBitrate?, opusApplication?, crop?, resize?, includeProjectLink?, audio?: auto|on|off, sampleRate?, audioChannels?, audioFormat?, loop?: bool (values as in setRenderSettings / setOutputModule)}",
+            "{comp?: id|name, template?: Render Settings template, format?: h264|hevc|av1|prores|uncompressed|webm|png|jpeg|tiff|exr|tga|gif|wav|aiff, output?: path|template, log?: errorsOnly|plusSettings|plusPerFrameInfo, quality?: best|draft|1-100 (jpeg, webm), resolution?: full|half|third|quarter|scale, proxyUse?, effects?, solo?, guideLayers?, colorDepth?, frameBlending?, fieldRender?, pulldown?, motionBlur?, timeSpan?: workArea|comp|custom, start?: s, end?: s, duration?: s, frameRate?: fps|null, skipExisting?: bool, storageOverflow?: bool, channels?: rgb|rgba|alpha, color?, bitrate?: kbps, webmBitrate?, keyframeInterval?, proresProfile?, profile?, level?, rateControl?, webmCodec?, audioBitrate?, opusApplication?, crop?, resize?, includeProjectLink?, audio?: auto|on|off, sampleRate?, audioChannels?, audioFormat?, loop?: bool (values as in setRenderSettings / setOutputModule)}",
             can_add,
             add
         ),
@@ -1037,7 +1056,7 @@ pub fn specs() -> Vec<CommandSpec> {
             "Output Module Settings...",
             [],
             None,
-            "{item?|index?, module?: n (1 = first), template?: name, format?: h264|hevc|av1|prores|uncompressed|webm|png|jpeg|tiff|exr|gif|wav|aiff, channels?: rgb|rgba|alpha, color?: straight|premultiplied, quality?: 1-100, bitrate?: kbps, webmBitrate?: bool, keyframeInterval?: frames (0 = auto), proresProfile?: proxy|lt|standard|hq|4444|4444xq, profile?: main|main10 (HEVC/AV1), level?: auto|4.1, rateControl?: bitrate|quality, webmCodec?: vp9|av1, audioBitrate?: Opus kbps, opusApplication?: audio|voice, crop?: bool|{useRoi?, roi?, top?, left?, bottom?, right?}, cropTop?, cropLeft?, cropBottom?, cropRight?, resize?: bool|{preset?, width?, height?, lockAspect?, quality?: low|high}, resizeWidth?, resizeHeight?, postRenderAction?: none|import|importAndReplace|setProxy, includeProjectLink?: bool, audio?: auto|on|off, sampleRate?, audioChannels?: mono|stereo, audioFormat?: 16|24|32, loop?: bool, output?}",
+            "{item?|index?, module?: n (1 = first), template?: name, format?: h264|hevc|av1|prores|uncompressed|webm|png|jpeg|tiff|exr|tga|gif|wav|aiff, channels?: rgb|rgba|alpha, color?: straight|premultiplied, quality?: 1-100, bitrate?: kbps, webmBitrate?: bool, keyframeInterval?: frames (0 = auto), proresProfile?: proxy|lt|standard|hq|4444|4444xq, profile?: main|main10 (HEVC/AV1), level?: auto|4.1, rateControl?: bitrate|quality, webmCodec?: vp9|av1, audioBitrate?: Opus kbps, opusApplication?: audio|voice, crop?: bool|{useRoi?, roi?, top?, left?, bottom?, right?}, cropTop?, cropLeft?, cropBottom?, cropRight?, resize?: bool|{preset?, width?, height?, lockAspect?, quality?: low|high}, resizeWidth?, resizeHeight?, postRenderAction?: none|import|importAndReplace|setProxy, includeProjectLink?: bool, audio?: auto|on|off, sampleRate?, audioChannels?: mono|stereo, audioFormat?: 16|24|32, loop?: bool, output?}",
             has_items,
             set_output_module
         ),

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

@@ -5,7 +5,11 @@
 //!   settings on the desktop, so dropping `.jsx` files in those folders works too. File ▸ Scripts
 //!   lists them with the bundled sample scripts and extensions ([`BUNDLED`]) and runs them by name; ScriptUI
 //!   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.
+//!   (`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
@@ -22,6 +26,23 @@ 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
+/// After Effects): never listed as File ▸ Scripts submenus.
+const RESERVED_FOLDERS: [&str; 3] = [PANELS_FOLDER, "Startup", "Shutdown"];
 /// The ScriptUI panels open when EffectCraft last quit (settings store), reopened at launch.
 pub const OPEN_PANELS_FILE: &str = "scriptui_panels.json";
 /// Scripts' `app.settings` in the settings store: `{section: {key: value}}`, as After Effects
@@ -111,7 +132,7 @@ pub const BUNDLED: &[(&str, bool, &str, &str)] = &[
 /// A script File ▸ Scripts (or the Window menu, for panels) offers.
 #[derive(Clone, Debug, PartialEq, Serialize)]
 pub struct ScriptEntry {
-    /// File name (`Rename Layers.jsx`): what the menus show and commands take.
+    /// File name (`Rename Layers.jsx`), or `Folder/File.jsx` in a subfolder: what commands take.
     pub name: String,
     /// In the ScriptUI Panels folder: opens as a dockable panel.
     pub panel: bool,
@@ -119,16 +140,23 @@ pub struct ScriptEntry {
     pub source: &'static str,
 }
 
+/// Whether `name` ends in `.jsx` or `.js` (any letter case).
 fn is_script(name: &str) -> bool {
     let l = name.to_ascii_lowercase();
     l.ends_with(".jsx") || l.ends_with(".js")
 }
 
-/// Whether `name` can name an installed script: a bare file name, never a path (names are joined
-/// onto the Scripts folders of the settings store, which takes them as relative paths), and on
-/// Windows none of the names [`windows_unsafe_name`] lists.
+/// Whether `name` can name an installed script: a file name, or `Folder/File` for one in a
+/// subfolder of a Scripts folder (one level, and not one of [`RESERVED_FOLDERS`]: `ScriptUI
+/// Panels/…`, `Startup/…`, `Shutdown/…`). Each part is a bare name, never a path (names are joined onto the Scripts folders of
+/// the settings store, which takes them as relative paths), and on Windows none of the names
+/// [`windows_unsafe_name`] lists.
 fn is_script_name(name: &str) -> bool {
-    is_bare_name(name) && !(cfg!(windows) && windows_unsafe_name(name))
+    let part = |n: &str| is_bare_name(n) && !(cfg!(windows) && windows_unsafe_name(n));
+    match name.split_once('/') {
+        Some((folder, file)) => part(folder) && part(file) && !RESERVED_FOLDERS.iter().any(|r| folder.eq_ignore_ascii_case(r)),
+        None => part(name),
+    }
 }
 
 /// One path component on every platform: not empty, `.` or `..`, and without `/`, `\` or NUL.
@@ -155,8 +183,13 @@ pub fn scripts(s: &Session) -> Vec<ScriptEntry> {
     let mut v: Vec<ScriptEntry> = vec![];
     if let Some(cfg) = &s.config {
         for (dir, panel) in [(SCRIPTS_DIR, false), (PANELS_DIR, true)] {
-            for n in cfg.list(dir).into_iter().filter(|n| is_script(n) && is_script_name(n)) {
-                v.push(ScriptEntry { name: n, panel, source: "installed" });
+            // The folder itself, then each subfolder, whose scripts are named `Folder/File.jsx`.
+            let subfolders = cfg.list_dirs(dir).into_iter().map(|f| (format!("{dir}/{f}"), format!("{f}/")));
+            for (folder, prefix) in std::iter::once((dir.to_string(), String::new())).chain(subfolders) {
+                let names = cfg.list(&folder).into_iter().map(|n| format!("{prefix}{n}"));
+                for n in names.filter(|n| is_script(n) && is_script_name(n)) {
+                    v.push(ScriptEntry { name: n, panel, source: "installed" });
+                }
             }
         }
     }
@@ -203,6 +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")
@@ -216,12 +250,19 @@ fn list(s: &mut Session, _: &Value) -> Result<Value> {
     Ok(json!(scripts(s)))
 }
 
+/// `file.uninstallScript {name}`: delete an installed script or panel at the top of the Scripts
+/// folders.
 fn uninstall(s: &mut Session, p: &Value) -> Result<Value> {
     let c = "file.uninstallScript";
     let name = str_p(p, "name").ok_or_else(|| bad(c, "missing `name`"))?;
     if !is_script(name) || !is_script_name(name) {
         return Err(bad(c, format!("`{name}` is not a script file name")));
     }
+    // A subfolder can be a link to files outside the settings folder (an extension's own
+    // folder), so only what Install puts at the top is removed, never a file through a folder.
+    if name.contains('/') {
+        return Err(bad(c, format!("`{name}` is in a subfolder: delete it there yourself (only scripts at the top of the Scripts folders are uninstalled)")));
+    }
     let cfg = s.config.clone().ok_or_else(|| bad(c, "no settings folder"))?;
     let mut removed = false;
     for dir in [SCRIPTS_DIR, PANELS_DIR] {
@@ -231,6 +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"))) }
 }
 
@@ -312,17 +354,98 @@ 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";
     let name = str_p(p, "name").ok_or_else(|| bad(c, "missing `name` (a script in the ScriptUI Panels folder)"))?.to_string();
-    let title = name.trim_end_matches(".jsx").trim_end_matches(".js").to_string();
+    let file = name.rsplit_once('/').map_or(name.as_str(), |(_, f)| f);
+    let title = file.trim_end_matches(".jsx").trim_end_matches(".js").to_string();
     if let Some(w) = s.script_ui.windows.iter().find(|w| w.kind == scriptui::WindowKind::Panel && w.script == name) {
         let id = w.id;
         s.events.push(Event::Frontend { command: c.into(), params: json!({"window": id}) });
         return Ok(json!({"window": id, "open": true}));
     }
-    let (_, code) = script_code(s, &name, Some(true)).or_else(|| script_code(s, &name, None)).ok_or_else(|| bad(c, format!("no ScriptUI panel `{name}`")))?;
+    // Only panels: a script opened as one would be remembered, then forgotten at the next launch.
+    let (_, code) = script_code(s, &name, Some(true)).ok_or_else(|| bad(c, format!("no ScriptUI panel `{name}`")))?;
     let out = super::file_more::run_js_named(s, &panel_wrapper(&title, &code), &name)?;
     let id = s.script_ui.windows.iter().rev().find(|w| w.kind == scriptui::WindowKind::Panel && w.script == name).map(|w| w.id);
     if let Some(id) = id {
@@ -338,6 +461,7 @@ fn open_panel(s: &mut Session, p: &Value) -> Result<Value> {
     Ok(json!({"window": id, "result": out}))
 }
 
+/// The commands of File ▸ Scripts, ScriptUI panels and windows, and script settings.
 pub fn specs() -> Vec<CommandSpec> {
     vec![
         cmd!(
@@ -358,14 +482,22 @@ pub fn specs() -> Vec<CommandSpec> {
             always,
             |s, p| install(s, p, true)
         ),
-        cmd!("file.uninstallScript", "Uninstall Script", [], None, "{name}", always, uninstall),
-        crate::query!("file.scripts.list", "List Scripts", "{} → [{name, panel, source: installed|sample|extension}]", list),
+        cmd!(
+            "file.uninstallScript",
+            "Uninstall Script",
+            [],
+            None,
+            "{name (a script at the top of a Scripts folder, not `Folder/File.jsx`)}",
+            always,
+            uninstall
+        ),
+        crate::query!("file.scripts.list", "List Scripts", "{} → [{name (`Folder/File.jsx` in a subfolder), panel, source: installed|sample|extension}]", list),
         cmd!(
             "window.scriptPanel",
             "ScriptUI Panel",
             [],
             None,
-            "{name (a script in the ScriptUI Panels folder, e.g. `Layer Tools.jsx`)} → opens it as a dockable panel",
+            "{name (a script in the ScriptUI Panels folder, e.g. `Layer Tools.jsx`, or `Folder/Panel.jsx` in a subfolder)} → opens it as a dockable panel",
             always,
             open_panel
         ),
@@ -378,6 +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",
@@ -427,10 +577,19 @@ 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
         ),
+        cmd!(
+            "scriptui.resize",
+            "Resize Script Window",
+            [],
+            None,
+            "{window?, size: [width, height] (pixels)} → the window takes the size, lays itself out again and its onResizing / onResize run (a docked ScriptUI panel gets its dock's size)",
+            always,
+            scriptui::resize
+        ),
         cmd!(
             "scriptui.close",
             "Close Script Window",
@@ -504,13 +663,15 @@ mod tests {
         }
     }
 
+    /// Bundled and ordinary script file names are accepted; paths are not.
     #[test]
     fn script_names_are_bare_file_names() {
         let more = ["..jsx", "a..b.js", "Äpfel ✓.jsx", "console.jsx", "Concert.jsx", "NULL.jsx", "COM10.jsx", "LPT.jsx"];
         for name in BUNDLED.iter().map(|b| b.0).chain(more) {
             assert!(is_script(name) && is_script_name(name), "{name}");
         }
-        for name in PATHS {
+        // `a/b.jsx` is a script in a folder (see below).
+        for name in PATHS.into_iter().filter(|n| *n != "a/b.jsx") {
             assert!(!is_script_name(name), "{name:?}");
         }
         for name in WINDOWS_ONLY {
@@ -528,6 +689,141 @@ mod tests {
         }
     }
 
+    /// `Folder/File.jsx` is accepted; deeper, upward, absolute and `\` names are not.
+    #[test]
+    fn script_names_may_have_one_folder() {
+        for name in ["Motion Kit/Animate.jsx", "a/b.jsx", "Äpfel/✓.js", "..jsx/x.jsx"] {
+            assert!(is_script_name(name), "{name:?}");
+        }
+        // Deeper, up, absolute, an empty part, a `\` path, and the panels' own folder in `Scripts`.
+        let refused = ["a/b/c.jsx", "../x.jsx", "a/../x.jsx", "./x.jsx", "a/..", "/x.jsx", "a//x.jsx", "a/", "a\\b.jsx", "a/b\\c.jsx", "a\0/x.jsx"];
+        for name in refused.into_iter().chain(["ScriptUI Panels/x.jsx", "scriptui panels/x.jsx"]) {
+            assert!(!is_script_name(name), "{name:?}");
+        }
+        for name in ["In:Out/x.jsx", "con/x.jsx", "x/COM1.jsx", "x./y.jsx"] {
+            assert_eq!(is_script_name(name), !cfg!(windows), "{name:?}");
+        }
+    }
+
+    /// Writes `code` to `rel` in the settings folder of [`session_in_tmp`]'s `root`.
+    fn put(root: &std::path::Path, rel: &str, code: &str) {
+        let p = root.join("settings").join(rel);
+        std::fs::create_dir_all(p.parent().unwrap()).unwrap();
+        std::fs::write(p, code).unwrap();
+    }
+
+    /// Every script command takes `Folder/File.jsx` names and refuses names outside one folder level.
+    #[test]
+    fn scripts_in_a_subfolder_are_listed_run_and_opened_as_folder_and_file() {
+        let (mut s, root) = session_in_tmp("folders");
+        put(&root, "Scripts/Tools/Hello.jsx", "hello");
+        put(&root, "Scripts/ScriptUI Panels/Motion Kit/Animate.jsx", "animate");
+        put(&root, "Scripts/ScriptUI Panels/Top.jsx", "top");
+        // Two folders deep: neither listed nor run.
+        put(&root, "Scripts/a/b/c.jsx", "too deep");
+        put(&root, "Scripts/ScriptUI Panels/Motion Kit/sub/Deep.jsx", "too deep");
+        let list = s.execute("file.scripts.list", json!({})).unwrap();
+        let installed: Vec<(&str, bool)> =
+            list.as_array().unwrap().iter().filter(|e| e["source"] == "installed").map(|e| (e["name"].as_str().unwrap(), e["panel"] == true)).collect();
+        assert_eq!(installed, [("Tools/Hello.jsx", false), ("Motion Kit/Animate.jsx", true), ("Top.jsx", true)]);
+        assert_eq!(s.execute("file.runScript", json!({"name": "Tools/Hello.jsx"})).unwrap()["ran"], "hello");
+        // A panel in a folder is titled after its file.
+        let r = s.execute("window.scriptPanel", json!({"name": "Motion Kit/Animate.jsx"})).unwrap();
+        let ran = r["result"]["ran"].as_str().unwrap_or_default();
+        assert!(ran.contains("animate") && ran.contains(r#"__uiDockPanel("Animate")"#), "{r}");
+        assert_eq!(script_code(&s, "Motion Kit/Animate.jsx", Some(true)), Some((true, "animate".to_string())));
+        // A script that is not a panel doesn't open as one.
+        for name in ["Tools/Hello.jsx", "Rename Layers.jsx"] {
+            assert!(bad_params(&s.execute("window.scriptPanel", json!({"name": name}))), "{name}");
+        }
+        for name in [
+            "../x.jsx",
+            "a/b/c.jsx",
+            "a\\b.jsx",
+            "Motion Kit/sub/Deep.jsx",
+            "ScriptUI Panels/Top.jsx",
+            "Startup/Run.jsx",
+            "shutdown/Run.jsx",
+            "Tools/../../../outside.jsx",
+        ] {
+            assert_eq!(script_code(&s, name, None), None, "{name:?}");
+            for c in ["file.runScript", "window.scriptPanel", "file.uninstallScript"] {
+                let r = s.execute(c, json!({"name": name}));
+                assert!(bad_params(&r), "{c} `{name}`: {r:?}");
+            }
+        }
+        assert!(["Scripts/a/b/c.jsx", "Scripts/ScriptUI Panels/Top.jsx"].iter().all(|p| root.join("settings").join(p).is_file()));
+        assert!(root.join("outside.jsx").is_file());
+        // Uninstall removes only scripts at the top; one in a folder is deleted there by hand.
+        for name in ["Tools/Hello.jsx", "Motion Kit/Animate.jsx"] {
+            assert!(bad_params(&s.execute("file.uninstallScript", json!({"name": name}))), "{name}");
+        }
+        assert!(["Scripts/Tools/Hello.jsx", "Scripts/ScriptUI Panels/Motion Kit/Animate.jsx"].iter().all(|p| root.join("settings").join(p).is_file()));
+        let _ = std::fs::remove_dir_all(&root);
+    }
+
+    /// A subfolder can be a link to an extension's own folder, outside the settings folder: its
+    /// scripts are listed and run from there, but uninstall never deletes through it.
+    #[cfg(unix)]
+    #[test]
+    fn uninstall_never_deletes_through_a_linked_subfolder() {
+        let (mut s, root) = session_in_tmp("linked");
+        std::fs::create_dir_all(root.join("extension")).unwrap();
+        std::fs::write(root.join("extension").join("Animate.jsx"), "animate").unwrap();
+        std::os::unix::fs::symlink(root.join("extension"), root.join("settings").join(PANELS_DIR).join("Motion Kit")).unwrap();
+        let list = s.execute("file.scripts.list", json!({})).unwrap();
+        assert!(list.as_array().unwrap().iter().any(|e| e["name"] == "Motion Kit/Animate.jsx" && e["panel"] == true), "{list}");
+        assert_eq!(script_code(&s, "Motion Kit/Animate.jsx", Some(true)), Some((true, "animate".to_string())));
+        let r = s.execute("file.uninstallScript", json!({"name": "Motion Kit/Animate.jsx"}));
+        assert!(bad_params(&r), "{r:?}");
+        assert!(root.join("extension").join("Animate.jsx").is_file(), "the extension's own file was deleted");
+        let _ = std::fs::remove_dir_all(&root);
+    }
+
+    /// Window ▸ Motion Kit ▸ Animate.jsx: a subfolder is a submenu named after it, where the folder
+    /// sorts; the entries outside folders stay as they were.
+    #[test]
+    fn a_subfolder_is_a_submenu() {
+        use crate::menus::{MenuNode, dynamic, dynamic_nodes};
+        let (s, root) = session_in_tmp("submenus");
+        put(&root, "Scripts/ScriptUI Panels/Motion Kit/Animate.jsx", "");
+        put(&root, "Scripts/ScriptUI Panels/Motion Kit/Rig.jsx", "");
+        put(&root, "Scripts/ScriptUI Panels/Top.jsx", "");
+        put(&root, "Scripts/Tools/Hello.jsx", "");
+        let cx = Default::default();
+        let item =
+            |label: &str, command: &str, name: &str| json!({"type": "item", "label": label, "command": command, "params": {"name": name}, "shortcut": null});
+        let menus = [
+            (
+                "scriptPanels",
+                json!({"type": "submenu", "label": "Motion Kit", "children": [
+                    item("Animate.jsx", "window.scriptPanel", "Motion Kit/Animate.jsx"),
+                    item("Rig.jsx", "window.scriptPanel", "Motion Kit/Rig.jsx"),
+                ]}),
+            ),
+            ("scripts", json!({"type": "submenu", "label": "Tools", "children": [item("Hello.jsx", "file.runScript", "Tools/Hello.jsx")]})),
+        ];
+        for (menu, folder) in menus {
+            let (nodes, _) = dynamic_nodes(&s, menu, &cx);
+            let (entries, _) = dynamic(&s, menu, &cx);
+            let items: Vec<_> = nodes.iter().filter_map(|n| if let MenuNode::Item(e) = n { Some(e) } else { None }).collect();
+            assert_eq!(items, entries.iter().filter(|e| !e.label.contains('/')).collect::<Vec<_>>(), "{menu}");
+            let folders: Vec<Value> = nodes.iter().filter(|n| matches!(n, MenuNode::Submenu { .. })).map(|n| serde_json::to_value(n).unwrap()).collect();
+            assert_eq!(folders, [folder], "{menu}");
+        }
+        let (panels, _) = dynamic_nodes(&s, "scriptPanels", &cx);
+        let labels: Vec<&str> = panels
+            .iter()
+            .filter_map(|n| match n {
+                MenuNode::Item(e) => Some(e.label.as_str()),
+                MenuNode::Submenu { label, .. } => Some(label),
+                _ => None,
+            })
+            .collect();
+        assert_eq!(labels, ["Ease Presets.jsx", "Layer Tools.jsx", "Motion Kit", "Top.jsx"]);
+        let _ = std::fs::remove_dir_all(&root);
+    }
+
     #[test]
     fn uninstall_takes_a_script_name_not_a_path() {
         let (mut s, root) = session_in_tmp("uninstall");
@@ -775,4 +1071,64 @@ 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/styles.rs

@@ -25,13 +25,23 @@ fn add_styles(s: &mut Session, p: &Value, cmd: &str, styles: &[&str], enabled: b
     if ids.is_empty() {
         return Err(bad(cmd, "no layer that takes layer styles (footage, solid, precomp, text or shape layer)"));
     }
-    let uids = s.edit(label, None, |proj, state| {
+    let uids = s.edit(label, super::merge_p(p), |proj, state| {
         let gl = proj.comp(cid).ok_or(EngineError::NoComp)?.global_light.clone();
         let mut out = vec![];
         let mut sel = vec![];
         for lid in &ids {
             let mut next = proj.next_id;
             let l = layer_mut(proj, cid, *lid)?;
+            // No style: Blending Options alone (the Layer Style dialog's first change on a layer
+            // without styles).
+            if styles.is_empty() {
+                let uid = st::add_blending_options(l, &mut Ids(&mut next), &gl).ok_or_else(|| bad(cmd, "no Blending Options"))?;
+                if let Some(g) = l.props.sub_mut(GROUP) {
+                    g.enabled = true;
+                }
+                out.push(json!({"layer": lid.0, "style": st::BLENDING, "uid": uid}));
+                sel.push((*lid, uid));
+            }
             for id in styles {
                 let had = l.layer_styles().and_then(|g| g.sub(id)).is_some();
                 let uid = st::add_style(l, &mut Ids(&mut next), id, &gl, enabled).ok_or_else(|| bad(cmd, format!("unknown style `{id}`")))?;
@@ -58,6 +68,9 @@ fn add_styles(s: &mut Session, p: &Value, cmd: &str, styles: &[&str], enabled: b
 
 fn add(s: &mut Session, p: &Value) -> Result<Value> {
     let name = str_p(p, "style").ok_or_else(|| bad("layer.style.add", "missing `style` (e.g. dropShadow or \"Drop Shadow\")"))?;
+    if name.eq_ignore_ascii_case(st::BLENDING) || name.eq_ignore_ascii_case("Blending Options") {
+        return add_styles(s, p, "layer.style.add", &[], true, "Blending Options");
+    }
     let id = st::style_id(name)
         .ok_or_else(|| bad("layer.style.add", format!("unknown style `{name}`; one of {}", STYLES.iter().map(|s| s.0).collect::<Vec<_>>().join(", "))))?;
     let label = STYLES.iter().find(|s| s.0 == id).map(|s| s.1).unwrap_or(id);
@@ -139,8 +152,9 @@ fn remove(s: &mut Session, p: &Value) -> Result<Value> {
                 return Err(bad("layer.style.remove", "Blending Options can't be removed"));
             }
             g.children.retain(|c| c.uid() != uid);
-            // The last style gone removes the Layer Styles group, as in AE.
-            if g.children.iter().all(|c| c.match_id() == st::BLENDING) {
+            // The last style gone removes the Layer Styles group, as in AE, unless its Blending
+            // Options were changed (they can be edited with no style since #1389).
+            if g.children.iter().all(|c| c.match_id() == st::BLENDING) && g.sub(st::BLENDING).is_none_or(st::blending_is_default) {
                 l.props.children.retain(|c| c.match_id() != GROUP);
             }
         }
@@ -224,7 +238,7 @@ pub fn specs() -> Vec<CommandSpec> {
             "Add Layer Style",
             [],
             None,
-            "{style: dropShadow|innerShadow|outerGlow|innerGlow|bevelEmboss|satin|colorOverlay|gradientOverlay|stroke (or display name), layers?}",
+            "{style: dropShadow|innerShadow|outerGlow|innerGlow|bevelEmboss|satin|colorOverlay|gradientOverlay|stroke (or display name), or blendingOptions (the Layer Styles group with Blending Options only), layers?, merge?}",
             has_layers,
             add
         ),

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
         ),