Merge the land-fix PRs integrated on land-r7 (#67 #87 #88 #136 #137 #139 #150 #151 #169 #209 #225 #247 #321)

README.md

@@ -150,6 +150,7 @@ deckcraft-cli commands format.          # list commands
 deckcraft-cli run --sample --cmd 'slide.new={"layout":"titleOnly","title":"Hello"}' --save hello.deckcraft
 deckcraft-cli mcp                       # MCP server over stdio (headless)
 deckcraft-cli mcp --connect 7990        # drive the running app (deckcraft --control 7990)
+deckcraft-cli mcp --automation-read-root DIR --automation-write-root DIR   # confine the headless agent to folders
 ```
 
 ## Roadmap

apps/deckcraft-cli/src/automation_args.rs

@@ -0,0 +1,90 @@
+//! Parse `--automation-read-root` / `--automation-write-root` before the server starts. A malformed
+//! flag must not silently remove a root and leave the server unconfined.
+
+use std::path::PathBuf;
+
+pub struct AutomationArgs {
+    pub read_root: Option<PathBuf>,
+    pub write_root: Option<PathBuf>,
+    read_given: bool,
+    write_given: bool,
+}
+
+impl AutomationArgs {
+    pub fn new(read_root: Option<PathBuf>, write_root: Option<PathBuf>) -> Self {
+        Self { read_root, write_root, read_given: false, write_given: false }
+    }
+
+    /// Returns whether this argument is a root flag. A second occurrence of a flag is an error,
+    /// including when the two spellings (`--flag DIR`, `--flag=DIR`) are mixed.
+    pub fn consume(&mut self, arg: &str, args: &mut impl Iterator<Item = String>) -> Result<bool, String> {
+        let (flag, inline) = arg.split_once('=').map_or((arg, None), |(flag, value)| (flag, Some(value)));
+        let (root, given) = match flag {
+            "--automation-read-root" => (&mut self.read_root, &mut self.read_given),
+            "--automation-write-root" => (&mut self.write_root, &mut self.write_given),
+            _ => return Ok(false),
+        };
+        if *given {
+            return Err(format!("{flag} given twice"));
+        }
+        let value = match inline {
+            Some(value) => value.to_owned(),
+            None => {
+                let value = args.next().ok_or_else(|| format!("{flag} needs a folder"))?;
+                if value.starts_with('-') {
+                    return Err(format!("{flag} needs a folder; use {flag}=<dir> for a folder starting with '-'"));
+                }
+                value
+            }
+        };
+        if value.is_empty() {
+            return Err(format!("{flag} needs a non-empty folder"));
+        }
+        *root = Some(value.into());
+        *given = true;
+        Ok(true)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn roots_are_taken_once_and_other_arguments_are_left() {
+        let mut roots = AutomationArgs::new(None, None);
+        let mut args = ["a folder".to_owned(), "deck.pptx".to_owned()].into_iter();
+        assert!(roots.consume("--automation-read-root", &mut args).unwrap());
+        assert!(roots.consume("--automation-write-root=out", &mut args).unwrap());
+        assert!(!roots.consume("--sample", &mut args).unwrap());
+        assert_eq!(roots.read_root, Some("a folder".into()));
+        assert_eq!(roots.write_root, Some("out".into()));
+        assert_eq!(args.next().as_deref(), Some("deck.pptx"));
+        assert!(roots.consume("--automation-read-root=other", &mut args).is_err());
+        assert_eq!(roots.read_root, Some("a folder".into()));
+    }
+
+    #[test]
+    fn invalid_operands_leave_roots_unchanged() {
+        for flag in ["--automation-read-root", "--automation-write-root"] {
+            for operand in [None, Some(""), Some("--version"), Some("--connect"), Some("-folder")] {
+                let mut roots = AutomationArgs::new(Some("read".into()), Some("write".into()));
+                let mut args = operand.map(str::to_owned).into_iter();
+                assert!(roots.consume(flag, &mut args).is_err(), "{flag} {operand:?}");
+                assert_eq!(roots.read_root, Some("read".into()));
+                assert_eq!(roots.write_root, Some("write".into()));
+            }
+            let mut roots = AutomationArgs::new(None, None);
+            assert!(roots.consume(&format!("{flag}="), &mut std::iter::empty()).is_err());
+        }
+    }
+
+    #[test]
+    fn explicit_dash_folder_and_relative_dash_folder_are_valid() {
+        let mut roots = AutomationArgs::new(None, None);
+        assert!(roots.consume("--automation-read-root=-folder", &mut std::iter::empty()).unwrap());
+        assert!(roots.consume("--automation-write-root", &mut ["./-folder".to_owned()].into_iter()).unwrap());
+        assert_eq!(roots.read_root, Some("-folder".into()));
+        assert_eq!(roots.write_root, Some("./-folder".into()));
+    }
+}

apps/deckcraft-cli/src/help.rs

@@ -126,11 +126,16 @@ and prints its answer as JSON. COMMAND [PARAMS] runs a command, as run --cmd doe
     },
     Subcommand {
         name: "mcp",
-        usage: "mcp [--connect PORT] [--sample]",
+        usage: "mcp [--connect PORT] [--sample] [--automation-read-root DIR] [--automation-write-root DIR]",
         summary: "serve the commands to an agent over MCP on stdio",
         details: "Runs a Model Context Protocol server on stdin and stdout. It works on its own presentation without a
 window, or with --connect PORT (or host:port) on the DeckCraft app started with --control PORT.
---sample opens the sample presentation.",
+--sample opens the sample presentation.
+
+--automation-read-root DIR and --automation-write-root DIR confine every file the agent's commands read
+(open, pictures, audio, video) and write (save, export, PDF) to those folders, links followed; a root left
+out grants none of its access. They run the in-process server, so they conflict with --connect (a running
+app is not confined by them).",
     },
     Subcommand {
         name: "bench",

apps/deckcraft-cli/src/main.rs

@@ -2,6 +2,8 @@
 #![deny(clippy::unwrap_used, clippy::expect_used, clippy::panic, clippy::unimplemented, clippy::todo, clippy::unreachable)]
 #![forbid(unsafe_code)]
 
+mod automation_args;
+
 mod help;
 
 use std::process::ExitCode;
@@ -584,13 +586,18 @@ fn app(args: &[String]) -> Result<(), String> {
 }
 
 fn mcp(args: &[String]) -> Result<(), String> {
+    use deckcraft_engine::file_access::{self, AutomationRoots};
     use deckcraft_mcp::{Backend, Headless, Remote, Server, control_addr};
     let mut connect: Option<String> = None;
     let mut sample = false;
-    let mut it = args.iter();
+    let mut roots_args = automation_args::AutomationArgs::new(None, None);
+    let mut it = args.iter().cloned();
     while let Some(a) = it.next() {
+        if roots_args.consume(&a, &mut it)? {
+            continue;
+        }
         match a.as_str() {
-            "--connect" => connect = Some(it.next().cloned().ok_or("--connect needs a port or host:port")?),
+            "--connect" => connect = Some(it.next().ok_or("--connect needs a port or host:port")?),
             "--sample" => sample = true,
             "--help" | "-h" => {
                 outln!("{}", help_page("mcp"));
@@ -599,13 +606,27 @@ fn mcp(args: &[String]) -> Result<(), String> {
             other => return Err(format!("unknown mcp option `{other}`")),
         }
     }
+    let roots = AutomationRoots::new(roots_args.read_root.as_deref(), roots_args.write_root.as_deref())?;
+    if roots.is_some() && connect.is_some() {
+        return Err("--automation-read-root and --automation-write-root confine the in-process server; a running app is not confined by them, \
+so drop --connect (or use --connect without the roots)"
+            .into());
+    }
     let backend: Box<dyn Backend> = match connect {
         Some(c) => Box::new(Remote::connect(&control_addr(&c)).map_err(|e| format!("can't reach the app at {c}: {e}"))?),
         None => {
             let mut h = Headless::new();
+            // `--sample` is the operator's own choice, made before the roots come into force.
             if sample {
                 deckcraft_engine::sample::open_sample(&mut h.session).map_err(|e| e.to_string())?;
             }
+            if let Some(roots) = roots {
+                // Every thread of this process, not only the server's: nothing reaches past the roots.
+                file_access::confine_process(roots.clone());
+                let show = |root: Option<&std::path::Path>| root.map_or_else(|| "none".to_string(), |r| r.display().to_string());
+                eprintln!("deckcraft-cli: files confined: read root {}, write root {}", show(roots.read_root()), show(roots.write_root()));
+                h = h.with_automation_roots(Some(roots));
+            }
             Box::new(h)
         }
     };

apps/deckcraft-cli/tests/mcp_roots.rs

@@ -0,0 +1,118 @@
+//! `deckcraft-cli mcp` with the automation root flags, run as the real binary.
+// Integration tests: unwrapping and panicking on failure is fine here, unlike in shipped code (AGENTS.md).
+#![allow(clippy::unwrap_used, clippy::expect_used, clippy::panic)]
+
+use std::io::Write;
+use std::path::PathBuf;
+use std::process::{Command, Output, Stdio};
+
+use serde_json::Value;
+
+fn bin() -> Command {
+    Command::new(env!("CARGO_BIN_EXE_deckcraft-cli"))
+}
+
+fn run(args: &[&str]) -> Output {
+    bin().args(args).output().unwrap()
+}
+
+fn tmpdir(tag: &str) -> PathBuf {
+    let dir = std::env::temp_dir().join(format!("dc-cli-{tag}-{}", std::process::id()));
+    let _ = std::fs::remove_dir_all(&dir);
+    std::fs::create_dir_all(&dir).unwrap();
+    dir
+}
+
+/// Send `calls` (tool name, arguments) to `deckcraft-cli mcp <args>`; returns whether it exited
+/// cleanly, its stderr, and the stdout lines after `initialize`, one per call.
+fn mcp_session(args: &[&str], calls: &[(&str, Value)]) -> (bool, String, Vec<Value>) {
+    let mut child = bin().arg("mcp").args(args).stdin(Stdio::piped()).stdout(Stdio::piped()).stderr(Stdio::piped()).spawn().unwrap();
+    {
+        let stdin = child.stdin.as_mut().unwrap();
+        writeln!(stdin, r#"{{"jsonrpc":"2.0","id":1,"method":"initialize","params":{{"protocolVersion":"2025-06-18"}}}}"#).unwrap();
+        for (i, (name, arguments)) in calls.iter().enumerate() {
+            let call = serde_json::json!({"jsonrpc": "2.0", "id": i + 2, "method": "tools/call", "params": {"name": name, "arguments": arguments}});
+            writeln!(stdin, "{call}").unwrap();
+        }
+    }
+    let out = child.wait_with_output().unwrap();
+    let stdout = String::from_utf8(out.stdout).unwrap();
+    let replies = stdout.lines().skip(1).map(|l| serde_json::from_str(l).unwrap()).collect();
+    (out.status.success(), String::from_utf8_lossy(&out.stderr).into_owned(), replies)
+}
+
+fn text(reply: &Value) -> &str {
+    reply["result"]["content"][0]["text"].as_str().unwrap()
+}
+
+#[test]
+fn mcp_automation_roots_confine_the_server() {
+    let base = tmpdir("roots");
+    let (work, elsewhere) = (base.join("work"), base.join("elsewhere"));
+    std::fs::create_dir_all(&work).unwrap();
+    std::fs::create_dir_all(&elsewhere).unwrap();
+    std::fs::write(work.join("in.txt"), "Inside text").unwrap();
+    std::fs::write(elsewhere.join("secret.txt"), "TOP SECRET").unwrap();
+    let work_s = work.to_str().unwrap();
+    let secret = elsewhere.join("secret.txt").to_str().unwrap().to_string();
+
+    // Both spellings of the flags; inside works, outside is refused with a readable message.
+    let read_flag = format!("--automation-read-root={work_s}");
+    let calls = [
+        ("open_presentation", serde_json::json!({"path": work.join("in.txt").to_str().unwrap()})),
+        ("open_presentation", serde_json::json!({"path": secret})),
+        ("save_presentation", serde_json::json!({"path": work.join("saved.deckcraft").to_str().unwrap()})),
+        ("save_presentation", serde_json::json!({"path": elsewhere.join("saved.deckcraft").to_str().unwrap()})),
+    ];
+    let (success, stderr, replies) = mcp_session(&[&read_flag, "--automation-write-root", work_s], &calls);
+    assert!(success, "{stderr}");
+    assert!(stderr.contains("files confined"), "{stderr}");
+    assert_eq!(replies[0]["result"]["isError"], false, "{}", replies[0]);
+    assert_eq!(replies[1]["result"]["isError"], true);
+    assert!(text(&replies[1]).contains("outside the read root"), "{}", text(&replies[1]));
+    assert_eq!(replies[2]["result"]["isError"], false, "{}", replies[2]);
+    assert!(work.join("saved.deckcraft").exists());
+    assert_eq!(replies[3]["result"]["isError"], true);
+    assert!(text(&replies[3]).contains("outside the write root"), "{}", text(&replies[3]));
+    assert!(!elsewhere.join("saved.deckcraft").exists());
+
+    // A root left out grants none of its access.
+    let save = [("new_presentation", serde_json::json!({})), calls[2].clone()];
+    let (_, _, replies) = mcp_session(&[&read_flag], &save);
+    assert_eq!(replies[1]["result"]["isError"], true);
+    assert!(text(&replies[1]).contains("write authority is absent"), "{}", text(&replies[1]));
+
+    // No flags: nothing is confined.
+    let (success, _, replies) = mcp_session(&[], &calls[1..2]);
+    assert!(success);
+    assert_eq!(replies[0]["result"]["isError"], false, "{}", replies[0]);
+    let _ = std::fs::remove_dir_all(base);
+}
+
+#[test]
+fn mcp_automation_root_flags_are_checked_up_front() {
+    let base = tmpdir("roots-args");
+    let dir = base.to_str().unwrap();
+    let missing = base.join("missing");
+    let fails = |args: &[&str], needle: &str| {
+        let mut full = vec!["mcp"];
+        full.extend_from_slice(args);
+        let o = run(&full);
+        assert!(!o.status.success(), "{args:?}");
+        let err = String::from_utf8_lossy(&o.stderr).into_owned();
+        assert!(err.contains(needle), "{args:?}: {err}");
+    };
+    // The flags confine the in-process server, so they cannot be combined with --connect.
+    fails(&["--connect", "7979", "--automation-read-root", dir], "--connect");
+    fails(&["--automation-write-root", dir, "--connect", "7979"], "--connect");
+    fails(&["--automation-read-root", dir, "--automation-read-root", dir], "given twice");
+    fails(&["--automation-write-root", dir, "--automation-write-root", dir], "given twice");
+    fails(&["--automation-read-root"], "needs a folder");
+    fails(&["--automation-write-root", "--sample"], "needs a folder");
+    fails(&["--automation-read-root", missing.to_str().unwrap()], "cannot open the automation read root");
+    fails(&["--automation-write-root="], "needs a non-empty folder");
+    // A file is not a folder.
+    std::fs::write(base.join("f.txt"), "x").unwrap();
+    fails(&["--automation-write-root", base.join("f.txt").to_str().unwrap()], "cannot open the automation write root");
+    let _ = std::fs::remove_dir_all(base);
+}

crates/anim/src/lib.rs

@@ -38,7 +38,7 @@ use serde::{Deserialize, Serialize};
 pub use easing::ease;
 pub use interact::{Click, HitShape, Target};
 pub use mesh::{MeshVertex, layer_mesh};
-pub use morph::{MorphFrame, MorphPath, MorphText, morph_frame, morph_pairs, morph_xfrm};
+pub use morph::{MorphFrame, MorphPath, MorphText, morph_crop, morph_frame, morph_pairs, morph_xfrm};
 pub use path::{MotionPath, default_path};
 pub use show::{LinkJump, ShowAction, ShowState, safe_url, show_order};
 pub use timeline::{EffectTiming, Sequence, StepStamp, Timeline, TriggerPlay};

crates/anim/src/morph.rs

@@ -12,7 +12,9 @@ fn text_of(s: &Shape) -> String {
 
 /// Pairs of (shape on `a`, shape on `b`) that Morph animates from one to the other: first by
 /// `!!name` (forced match), then by exact name, then by the same kind and text, then by the same
-/// kind and preset geometry. Each shape is used once; top-level shapes only (groups move whole).
+/// kind and preset geometry if neither carries text. A text box with neither a name nor its text on
+/// the other slide stays unpaired and fades in place, as in PowerPoint (#119). Each shape is used
+/// once; top-level shapes only (groups move whole).
 pub fn morph_pairs(a: &Slide, b: &Slide) -> Vec<(ShapeId, ShapeId)> {
     let mut pairs: Vec<(ShapeId, ShapeId)> = Vec::new();
     let mut used_a = vec![false; a.shapes.len()];
@@ -31,7 +33,8 @@ pub fn morph_pairs(a: &Slide, b: &Slide) -> Vec<(ShapeId, ShapeId)> {
             x.kind_name() == y.kind_name()
                 && x.geom.preset_name().is_some()
                 && x.geom.preset_name() == y.geom.preset_name()
-                && text_of(x).trim().is_empty() == text_of(y).trim().is_empty()
+                && text_of(x).trim().is_empty()
+                && text_of(y).trim().is_empty()
         },
     ];
     for pass in passes {
@@ -173,9 +176,58 @@ fn reshaped(a: &Shape, b: &Shape) -> bool {
     a.geom != b.geom && outlined(a) && outlined(b) && Shape { geom: Geom::default(), ..content(a) } == Shape { geom: Geom::default(), ..content(b) }
 }
 
+/// The content of a shape apart from what Morph interpolates, with a picture's crop left out.
+fn uncropped(s: &Shape) -> Shape {
+    let mut c = content(s);
+    if let ShapeKind::Picture { fill } = &mut c.kind {
+        fill.crop = [0.0; 4];
+    }
+    c
+}
+
+fn crop_of(s: &Shape) -> [f64; 4] {
+    match &s.kind {
+        ShapeKind::Picture { fill } => fill.crop,
+        _ => [0.0; 4],
+    }
+}
+
+/// Whether two pictures differ in their crop only (apart from box and fill), so the crop can morph.
+fn recropped(a: &Shape, b: &Shape) -> bool {
+    matches!(a.kind, ShapeKind::Picture { .. }) && crop_of(a) != crop_of(b) && uncropped(a) == uncropped(b)
+}
+
+/// The crop (left, top, right, bottom) of a picture morphing from box `xa` cropped by `ca` to box
+/// `xb` cropped by `cb`, when its box is `x` at progress `t`: the whole image moves and scales
+/// linearly between where it lies on either slide, and the crop is what of it `x` shows. Falls back
+/// to blending the crops when a crop leaves nothing visible.
+pub fn morph_crop(ca: [f64; 4], xa: Xfrm, cb: [f64; 4], xb: Xfrm, x: Xfrm, t: f64) -> [f64; 4] {
+    // Along one axis: (box start, box size, crop before, crop after) → the crops at `t`.
+    let axis = |(pa, sa, la, ha): (f64, f64, f64, f64), (pb, sb, lb, hb): (f64, f64, f64, f64), (p, s): (f64, f64)| {
+        let (va, vb) = (1.0 - la - ha, 1.0 - lb - hb);
+        if va <= 1e-6 || vb <= 1e-6 {
+            return (lerp(la, lb, t), lerp(ha, hb, t));
+        }
+        // The whole image: its extent and start on either slide.
+        let (ea, eb) = (sa / va, sb / vb);
+        let e = lerp(ea, eb, t);
+        if !e.is_finite() || e.abs() <= 1e-9 {
+            return (lerp(la, lb, t), lerp(ha, hb, t));
+        }
+        let o = lerp(pa - la * ea, pb - lb * eb, t);
+        let lo = (p - o) / e;
+        (lo, 1.0 - lo - s / e)
+    };
+    let (l, r) = axis((xa.x, xa.w, ca[0], ca[2]), (xb.x, xb.w, cb[0], cb[2]), (x.x, x.w));
+    let (tp, bt) = axis((xa.y, xa.h, ca[1], ca[3]), (xb.y, xb.h, cb[1], cb[3]), (x.y, x.h));
+    let c = [l, tp, r, bt];
+    if c.iter().all(|v| v.is_finite()) { c } else { cb }
+}
+
 /// Morph frame from slide `a` to slide `b` at progress `t` (0..1, eased here). Paired shapes
 /// ([`morph_pairs`]) move along [`morph_xfrm`]; when they differ only in solid fill colour the
-/// colour blends, when only in geometry (and fill colour) the outline morphs ([`MorphFrame::paths`]),
+/// colour blends, when pictures differ only in crop the crop morphs ([`morph_crop`]), when only
+/// in geometry (and fill colour) the outline morphs ([`MorphFrame::paths`]),
 /// otherwise the new shape fades in under the fading old one on the same moving
 /// box; with the transition option `words` or `characters` their texts are listed in
 /// [`MorphFrame::text`] to morph word by word or character by character. Unpaired shapes of `a` fade out, unpaired shapes of `b` fade in, and shapes of `b` for
@@ -223,8 +275,18 @@ pub fn morph_frame(pres: &Presentation, a: &Slide, b: &Slide, t: f64, hidden_b:
             (_, xb) => xb,
         };
         let reshape = reshaped(sa, sb);
-        if reshape || content(sa) == content(sb) {
+        let recrop = recropped(sa, sb);
+        if reshape || recrop || content(sa) == content(sb) {
             let mut m = Shape { xfrm: x, ..sb.clone() };
+            if recrop && let ShapeKind::Picture { fill } = &mut m.kind {
+                fill.crop = match (xa, xb, x) {
+                    (Some(xa), Some(xb), Some(x)) => morph_crop(crop_of(sa), xa, crop_of(sb), xb, x, s),
+                    _ => {
+                        let (ca, cb) = (crop_of(sa), crop_of(sb));
+                        [lerp(ca[0], cb[0], s), lerp(ca[1], cb[1], s), lerp(ca[2], cb[2], s), lerp(ca[3], cb[3], s)]
+                    }
+                };
+            }
             if let (Some(fa), Some(fb)) = (solid_color(ca.as_ref(), sa), solid_color(cb.as_ref(), sb))
                 && fa != fb
             {

crates/anim/src/tests.rs

@@ -529,6 +529,61 @@ fn morph_pairs_by_name_text_and_geometry() {
     assert!(morph_pairs(&Slide::default(), &b).is_empty());
 }
 
+#[test]
+fn morph_pairs_leaves_unrelated_text_boxes_alone() {
+    // A text box that leaves and an unrelated one that arrives fade in place (#119).
+    let p = deckcraft_model::defaults::new_presentation(None);
+    let mut a = Slide::default();
+    let mut b = Slide::default();
+    let tb = |id, name, x, text| Shape { xfrm: Some(Xfrm::new(x, 100.0, 200.0, 100.0)), text: Some(TextBody::from_text(text)), ..shape(id, name) };
+    a.shapes = vec![tb(1, "TextBox 1", 0.0, "Gone")];
+    b.shapes = vec![tb(2, "TextBox 2", 400.0, "New")];
+    assert!(morph_pairs(&a, &b).is_empty());
+    let f = morph_frame(&p, &a, &b, 0.5, &|_| false);
+    let xs: Vec<(&str, f64)> = f.shapes.iter().map(|(s, _)| (s.name.as_str(), s.xfrm.map_or(f64::NAN, |x| x.x))).collect();
+    assert_eq!(xs, [("TextBox 1", 0.0), ("TextBox 2", 400.0)]);
+    // Empty shapes of one kind and geometry still pair, and a named text box keeps its partner.
+    a.shapes.push(shape(3, "Rect A"));
+    b.shapes.push(shape(4, "Rect B"));
+    b.shapes[0].name = "TextBox 1".into();
+    assert_eq!(morph_pairs(&a, &b), [(ShapeId(1), ShapeId(2)), (ShapeId(3), ShapeId(4))]);
+}
+
+#[test]
+fn morph_crop_moves_the_image_linearly() {
+    let bx = |x, w| Xfrm::new(x, 0.0, w, 100.0);
+    // Same box, the crop pans from the left half to the right half of a 200-wide image.
+    let c = morph_crop([0.0, 0.0, 0.5, 0.0], bx(0.0, 100.0), [0.5, 0.0, 0.0, 0.0], bx(0.0, 100.0), bx(0.0, 100.0), 0.5);
+    assert!(c.iter().zip([0.25, 0.0, 0.25, 0.0]).all(|(a, b)| (a - b).abs() < 1e-9), "{c:?}");
+    // The box shrinks over an image that stays put: only the right crop grows.
+    let c = morph_crop([0.0; 4], bx(0.0, 100.0), [0.0, 0.0, 0.5, 0.0], bx(0.0, 50.0), bx(0.0, 75.0), 0.5);
+    assert!(c.iter().zip([0.0, 0.0, 0.25, 0.0]).all(|(a, b)| (a - b).abs() < 1e-9), "{c:?}");
+    // Nothing visible on one side: the crops blend.
+    let c = morph_crop([0.5, 0.0, 0.5, 0.0], bx(0.0, 100.0), [0.0; 4], bx(0.0, 100.0), bx(0.0, 100.0), 0.5);
+    assert!(c.iter().all(|v| v.is_finite()) && (c[0] - 0.25).abs() < 1e-9, "{c:?}");
+}
+
+#[test]
+fn morph_frame_morphs_a_picture_crop() {
+    // A picture recropped on the next slide stays one picture whose crop morphs (#118).
+    let p = deckcraft_model::defaults::new_presentation(None);
+    let pic = |id, crop| Shape {
+        kind: deckcraft_model::ShapeKind::Picture { fill: deckcraft_model::style::PictureFill { crop, ..Default::default() } },
+        ..shape(id, "Picture 1")
+    };
+    let mut a = Slide::default();
+    let mut b = Slide::default();
+    a.shapes = vec![pic(1, [0.0, 0.0, 0.5, 0.0])];
+    b.shapes = vec![pic(2, [0.5, 0.0, 0.0, 0.0])];
+    let f = morph_frame(&p, &a, &b, 0.5, &|_| false);
+    assert_eq!(f.shapes.len(), 1);
+    assert!(f.opacity.is_empty());
+    let deckcraft_model::ShapeKind::Picture { fill } = &f.shapes[0].0.kind else { panic!("not a picture") };
+    let want = 0.5 * f.mix;
+    assert!((fill.crop[0] - want).abs() < 1e-9 && (fill.crop[2] - (0.5 - want)).abs() < 1e-9, "{:?}", fill.crop);
+    assert_eq!(morph_frame(&p, &a, &b, 1.0, &|_| false).shapes[0].0.kind, b.shapes[0].kind);
+}
+
 #[test]
 fn morph_xfrm_interpolates() {
     let a = Xfrm { rot: 350.0, ..Xfrm::new(0.0, 0.0, 100.0, 100.0) };

crates/engine/src/cmd/design.rs

@@ -152,7 +152,7 @@ fn browse_theme(s: &mut Session, p: &Value) -> Result<Value> {
         #[cfg(not(target_arch = "wasm32"))]
         {
             let path = str_param(p, "path").ok_or_else(|| bad("design.browseTheme", "give `path` or `data`"))?;
-            std::fs::read(path).map_err(|e| crate::EngineError::Other(format!("{path}: {e}")))?
+            crate::io::read_file(path).map_err(crate::EngineError::Other)?
         }
         #[cfg(target_arch = "wasm32")]
         return Err(bad("design.browseTheme", "give `data`"));

crates/engine/src/cmd/file.rs

@@ -165,7 +165,7 @@ pub fn add_opened(s: &mut Session, name: &str, path: Option<String>, p: Presenta
 #[cfg(not(target_arch = "wasm32"))]
 fn open(s: &mut Session, p: &Value) -> Result<Value> {
     let path = str_param(p, "path").ok_or_else(|| bad("file.open", "missing `path`"))?;
-    let bytes = std::fs::read(path).map_err(|e| EngineError::Other(format!("{path}: {e}")))?;
+    let bytes = crate::io::read_file(path).map_err(EngineError::Other)?;
     let (doc, damaged) = open_checked(path, &bytes)?;
     let native = deckcraft_format::sniff(&bytes) || deckcraft_pptx::sniff(&bytes);
     // A damaged file opens as an untitled repaired copy, so Save can't overwrite the original
@@ -340,36 +340,8 @@ fn mark_saved(s: &mut Session, path: Option<String>) -> Result<()> {
     Ok(())
 }
 
-#[cfg(not(target_arch = "wasm32"))]
 fn write_file(path: &str, bytes: &[u8]) -> Result<()> {
-    use std::io::Write;
-    use std::sync::atomic::{AtomicU64, Ordering};
-    static COUNTER: AtomicU64 = AtomicU64::new(0);
-    let err = |e: std::io::Error| EngineError::Other(format!("{path}: {e}"));
-    // Write to a uniquely named temporary sibling, created exclusively (never following or reusing an
-    // existing file or symlink), then rename it over the destination so a failed save never truncates
-    // the old file and concurrent saves never share temporary bytes.
-    let mut attempts = 0;
-    let (tmp, mut file) = loop {
-        let tmp = format!("{path}.{}.{}.saving", std::process::id(), COUNTER.fetch_add(1, Ordering::Relaxed));
-        match std::fs::OpenOptions::new().write(true).create_new(true).open(&tmp) {
-            Ok(f) => break (tmp, f),
-            Err(e) if e.kind() == std::io::ErrorKind::AlreadyExists && attempts < 16 => attempts += 1,
-            Err(e) => return Err(err(e)),
-        }
-    };
-    let written = file.write_all(bytes).and_then(|()| file.sync_all());
-    drop(file);
-    let result = written.and_then(|()| std::fs::rename(&tmp, path));
-    if let Err(e) = result {
-        let _ = std::fs::remove_file(&tmp);
-        return Err(err(e));
-    }
-    Ok(())
-}
-#[cfg(target_arch = "wasm32")]
-fn write_file(_path: &str, _bytes: &[u8]) -> Result<()> {
-    Err(EngineError::Other("saving to a path is not available in the browser".into()))
+    crate::io::write_file(path, bytes).map_err(EngineError::Other)
 }
 
 fn save(s: &mut Session, p: &Value) -> Result<Value> {
@@ -529,7 +501,7 @@ fn info(s: &mut Session, _p: &Value) -> Result<Value> {
     let st = s.doc()?;
     let doc = &st.doc;
     #[cfg(not(target_arch = "wasm32"))]
-    let bytes = st.path.as_ref().and_then(|p| std::fs::metadata(p).ok()).map(|m| m.len());
+    let bytes = st.path.as_deref().and_then(crate::io::file_len);
     #[cfg(target_arch = "wasm32")]
     let bytes: Option<u64> = None;
     Ok(json!({

crates/engine/src/cmd/insert.rs

@@ -308,9 +308,8 @@ pub(crate) fn media_bytes(p: &Value, cmd: &str) -> Result<(String, Vec<u8>)> {
         let bytes = base64_decode(d).ok_or_else(|| bad(cmd, "invalid base64 `data`"))?;
         return Ok((str_param(p, "name").unwrap_or("media").to_string(), bytes));
     }
-    #[cfg(not(target_arch = "wasm32"))]
     if let Some(path) = str_param(p, "path") {
-        let bytes = std::fs::read(path).map_err(|e| EngineError::Other(format!("{path}: {e}")))?;
+        let bytes = crate::io::read_file(path).map_err(EngineError::Other)?;
         let name = std::path::Path::new(path).file_name().map(|n| n.to_string_lossy().to_string()).unwrap_or_else(|| "media".into());
         return Ok((name, bytes));
     }

crates/engine/src/cmd/review.rs

@@ -639,7 +639,7 @@ fn revised_bytes(p: &Value) -> Result<(String, Vec<u8>)> {
     }
     #[cfg(not(target_arch = "wasm32"))]
     if let Some(path) = str_param(p, "path") {
-        let bytes = std::fs::read(path).map_err(|e| crate::EngineError::Other(format!("{path}: {e}")))?;
+        let bytes = crate::io::read_file(path).map_err(crate::EngineError::Other)?;
         return Ok((path.to_string(), bytes));
     }
     Err(bad("review.compare", "give `path` or `data`"))

crates/engine/src/cmd/text.rs

@@ -5,7 +5,7 @@ use std::sync::Arc;
 use deckcraft_geom::{Affine, Point, Rect};
 use deckcraft_model::edit::{self as ed, Pos};
 use deckcraft_model::resolve::{self, Ctx};
-use deckcraft_model::text::{AutoFit, Hyperlink, Run, RunKind, RunProps, TextBody};
+use deckcraft_model::text::{Align, AutoFit, Hyperlink, Paragraph, Run, RunKind, RunProps, TextBody};
 use deckcraft_model::{Presentation, Shape, ShapeId, ShapeKind};
 use serde_json::{Value, json};
 
@@ -259,6 +259,22 @@ pub fn caret_line(st: &DocState, t: &TextSel) -> Option<(deckcraft_geom::Point,
     Some((m * deckcraft_geom::Point::new(cx, top), m * deckcraft_geom::Point::new(cx, bot)))
 }
 
+/// The colour of text typed at the caret. The canvas draws the caret in it, so the caret shows
+/// wherever the text does: light on a dark slide, dark on a light one. `None` when that text
+/// has no fill to take a colour from.
+pub fn caret_color(st: &DocState, t: &TextSel) -> Option<deckcraft_color::Rgba> {
+    if t.notes || t.cell.is_some() {
+        return None;
+    }
+    let sh = st.shape(t.shape)?;
+    let body = sh.text.as_ref()?;
+    let ctx = ctx_for(&st.doc, &st.selection)?;
+    let blank = Paragraph::default();
+    let para = body.paragraphs.get(t.caret.0).unwrap_or(&blank);
+    let props = resolve::run(&ctx, sh, para, &ed::props_at(body, t.caret));
+    Some(resolve::text_color(&ctx, &props)).filter(|c| c.a > 0)
+}
+
 fn pos_param(p: &Value, key: &str) -> Option<Pos> {
     let a = p.get(key)?.as_array()?;
     Some((a.first()?.as_u64()? as usize, a.get(1)?.as_u64()? as usize))
@@ -330,6 +346,7 @@ fn typed(s: &Session, body: &TextBody, at: Pos, text: &str) -> String {
 }
 
 pub(crate) fn insert_text(s: &mut Session, text: &str, props: Option<RunProps>) -> Result<Value> {
+    let inherited = inherited_aligns_for_edit(s);
     let text = {
         let st = s.doc()?;
         match &st.selection.text {
@@ -347,12 +364,53 @@ pub(crate) fn insert_text(s: &mut Session, text: &str, props: Option<RunProps>)
         let c = ed::insert(body, at, &text, props);
         t.anchor = c;
         t.caret = c;
+        for pi in at.0..=c.0 {
+            if let Some(para) = body.paragraphs.get_mut(pi) {
+                promote_rtl_if_needed(para, &inherited);
+            }
+        }
         c
     })?;
     autocorrect(s, text.chars().count() == 1)?;
     Ok(json!({"caret": [pos.0, pos.1]}))
 }
 
+/// Per outline level (0..=8), whether shape `id` on the current slide already resolves an
+/// alignment for its paragraphs (its own list style, the layout's or the master's). All `false`
+/// when the shape can't be resolved (notes, a shape that is gone).
+fn inherited_aligns(s: &Session, id: ShapeId) -> [bool; 9] {
+    let mut out = [false; 9];
+    let Ok(st) = s.doc() else { return out };
+    let Some(sh) = st.shape(id) else { return out };
+    let Some(ctx) = ctx_for(&st.doc, &st.selection) else { return out };
+    for (lvl, set) in out.iter_mut().enumerate() {
+        let para = deckcraft_model::text::Paragraph { level: lvl as u8, ..Default::default() };
+        *set = resolve::para(&ctx, sh, &para).align.is_some();
+    }
+    out
+}
+
+/// The aligns [`inherited_aligns`] gives for the text being edited (none for notes).
+fn inherited_aligns_for_edit(s: &Session) -> [bool; 9] {
+    match s.doc().ok().and_then(|st| st.selection.text.clone()) {
+        Some(t) if !t.notes => inherited_aligns(s, t.shape),
+        _ => [false; 9],
+    }
+}
+
+/// A paragraph with no direction of its own whose first strong character is right-to-left
+/// (Arabic, Hebrew, Kurdish…) becomes right-to-left, and right-aligned when nothing (the
+/// paragraph or what it inherits, `inherited`) sets its alignment.
+fn promote_rtl_if_needed(para: &mut deckcraft_model::text::Paragraph, inherited: &[bool; 9]) {
+    if para.props.rtl.is_none() && deckcraft_model::bidi::first_strong_is_rtl(&para.text()) {
+        para.props.rtl = Some(true);
+        let inherits_align = inherited.get(usize::from(para.level)).copied().unwrap_or(false);
+        if para.props.align.is_none() && !inherits_align {
+            para.props.align = Some(Align::Right);
+        }
+    }
+}
+
 /// Typing right after a hyperlink doesn't extend it (as in PowerPoint): at the end of a linked
 /// run, the props to type with are the run's without the link. `None` elsewhere.
 fn unlinked_at_link_end(body: &TextBody, at: Pos) -> Option<RunProps> {
@@ -623,12 +681,18 @@ fn autocorrect_options(s: &mut Session, p: &Value) -> Result<Value> {
 }
 
 pub(crate) fn paste_body(s: &mut Session, src: &TextBody) -> Result<Value> {
+    let inherited = inherited_aligns_for_edit(s);
     let pos = edit_text(s, |body, t| {
         let (a, b) = t.ordered();
         let at = ed::delete(body, a, b);
         let c = ed::insert_body(body, at, src);
         t.anchor = c;
         t.caret = c;
+        for pi in at.0..=c.0 {
+            if let Some(para) = body.paragraphs.get_mut(pi) {
+                promote_rtl_if_needed(para, &inherited);
+            }
+        }
         c
     })?;
     Ok(json!({"caret": [pos.0, pos.1]}))
@@ -1062,6 +1126,7 @@ fn set(s: &mut Session, p: &Value) -> Result<Value> {
         None => s.doc()?.selection.shapes.first().copied().ok_or_else(|| bad("text.set", "missing `id` (or select a shape)"))?,
     };
     let cell = p.get("cell").and_then(Value::as_array).and_then(|a| Some((a.first()?.as_u64()? as usize, a.get(1)?.as_u64()? as usize)));
+    let inherited = inherited_aligns(s, id);
     edit_shapes(s, &json!({"id": id}), "text.set", |sh| {
         let target = match (&mut sh.kind, cell) {
             (ShapeKind::Table(t), Some((r, c))) => t.cell_mut(r, c).map(|x| &mut x.text),
@@ -1080,6 +1145,7 @@ fn set(s: &mut Session, p: &Value) -> Result<Value> {
                 para.level = *lv;
                 para.props = pp.clone();
             }
+            promote_rtl_if_needed(para, &inherited);
             for r in &mut para.runs {
                 r.props = keep.clone();
             }
@@ -1289,6 +1355,30 @@ fn replace_font(s: &mut Session, p: &Value) -> Result<Value> {
     Ok(json!({"replaced": n}))
 }
 
+#[cfg(test)]
+mod rtl_promote_tests {
+    use deckcraft_model::text::{Align, Paragraph, Run};
+
+    use super::promote_rtl_if_needed;
+
+    fn para(text: &str) -> Paragraph {
+        Paragraph { runs: vec![Run::new(text)], ..Default::default() }
+    }
+
+    #[test]
+    fn right_aligns_only_when_no_alignment_is_set_or_inherited() {
+        let mut p = para("مرحبا");
+        promote_rtl_if_needed(&mut p, &[false; 9]);
+        assert_eq!((p.props.rtl, p.props.align), (Some(true), Some(Align::Right)));
+        let mut p = para("مرحبا");
+        promote_rtl_if_needed(&mut p, &[true; 9]);
+        assert_eq!((p.props.rtl, p.props.align), (Some(true), None));
+        let mut p = para("Hello مرحبا");
+        promote_rtl_if_needed(&mut p, &[false; 9]);
+        assert_eq!((p.props.rtl, p.props.align), (None, None));
+    }
+}
+
 #[cfg(test)]
 mod replace_font_tests {
     use serde_json::json;

crates/engine/src/file_access.rs

@@ -0,0 +1,483 @@
+//! The folders automation may read and write.
+//!
+//! `deckcraft-cli mcp --automation-read-root <dir> --automation-write-root <dir>` confines the
+//! files an agent's commands reach. [`AutomationRoots`] holds the two folders. While they are in force, every path a command
+//! reads goes through [`check_read`] and every path it writes through [`check_write`]:
+//!
+//! - The path is made absolute against the working directory, as the file system reads it. Its
+//!   links are followed: for a file that doesn't exist yet, the links of its nearest existing
+//!   folder, the rest of the path being plain names (`..` below a missing folder is refused, and so
+//!   is a link that leads nowhere).
+//! - The result must lie inside the root, compared by whole components (`/work2` isn't inside
+//!   `/work`), without regard to case on Windows.
+//! - Read and write access are separate: a root given alone grants only its own kind of access.
+//!
+//! Roots are in force on a thread inside [`confine`], and in the whole process after
+//! [`confine_process`] (`deckcraft-cli mcp`), except inside [`unconfined`]. Without roots
+//! nothing is checked.
+//!
+//! A path is checked, then opened: a process that can change the folders in between (swapping in
+//! a link) can still win that race. The roots keep an agent to the files it was given; they don't
+//! guard against other programs on the computer.
+
+use std::cell::RefCell;
+use std::ffi::OsString;
+use std::path::{Component, Path, PathBuf};
+use std::sync::{Arc, OnceLock};
+
+/// Read access or write access.
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+pub enum Access {
+    Read,
+    Write,
+}
+
+/// The folders automation may read and write; a root left out grants no access of its kind.
+#[derive(Debug)]
+pub struct AutomationRoots {
+    read: Option<Root>,
+    write: Option<Root>,
+}
+
+#[derive(Debug)]
+struct Root {
+    /// The folder made absolute, links followed: what paths are compared with.
+    resolved: PathBuf,
+    /// The same without Windows' `\\?\` prefix, for people.
+    shown: PathBuf,
+}
+
+impl Root {
+    /// The folder at `path`, which must exist.
+    fn open(path: &Path, access: Access) -> Result<Self, String> {
+        let kind = match access {
+            Access::Read => "read",
+            Access::Write => "write",
+        };
+        let resolved = std::fs::canonicalize(path)
+            .and_then(|p| if p.is_dir() { Ok(p) } else { Err(std::io::ErrorKind::NotADirectory.into()) })
+            .map_err(|e| format!("cannot open the automation {kind} root `{}`: {e}", path.display()))?;
+        Ok(Self { shown: plain(resolved.clone()), resolved })
+    }
+}
+
+impl AutomationRoots {
+    /// The roots `read` and `write`, which must be existing folders; `None` when neither is given
+    /// (nothing is confined then).
+    pub fn new(read: Option<&Path>, write: Option<&Path>) -> Result<Option<Arc<Self>>, String> {
+        if read.is_none() && write.is_none() {
+            return Ok(None);
+        }
+        let read = read.map(|p| Root::open(p, Access::Read)).transpose()?;
+        let write = write.map(|p| Root::open(p, Access::Write)).transpose()?;
+        Ok(Some(Arc::new(Self { read, write })))
+    }
+
+    /// The read root, absolute with its links followed.
+    pub fn read_root(&self) -> Option<&Path> {
+        self.read.as_ref().map(|r| r.shown.as_path())
+    }
+
+    /// The write root, absolute with its links followed.
+    pub fn write_root(&self) -> Option<&Path> {
+        self.write.as_ref().map(|r| r.shown.as_path())
+    }
+
+    /// May the file or folder at `path` be read (or written)? `Err` says why not.
+    pub fn check(&self, path: &str, access: Access) -> Result<(), String> {
+        let root = match access {
+            Access::Read => self.read.as_ref(),
+            Access::Write => self.write.as_ref(),
+        };
+        let Some(Root { resolved: folder, shown }) = root else {
+            return match access {
+                Access::Read => Err(format!("automation filesystem access is not granted: read authority is absent: {path}")),
+                Access::Write => Err(format!("automation filesystem access is not granted: write authority is absent: {path}")),
+            };
+        };
+        if inside(&resolve(path)?, folder) {
+            return Ok(());
+        }
+        let root = shown.display();
+        match access {
+            Access::Read => Err(format!("automation path rejected: outside the read root {root}: {path}")),
+            Access::Write => Err(format!("automation path rejected: outside the write root {root}: {path}")),
+        }
+    }
+}
+
+/// Where the roots are in force on a thread ([`confine`], [`unconfined`]).
+#[derive(Clone, Debug)]
+enum Scope {
+    Confined(Arc<AutomationRoots>),
+    Unconfined,
+}
+
+thread_local! {
+    /// This thread's scope; `None`: the process's roots ([`confine_process`]).
+    static SCOPE: RefCell<Option<Scope>> = const { RefCell::new(None) };
+}
+
+/// The roots in force in every thread outside [`confine`] and [`unconfined`].
+static PROCESS: OnceLock<Arc<AutomationRoots>> = OnceLock::new();
+
+/// Put `roots` in force in the whole process, for good. `false` when roots were in force already
+/// (they stay as they were).
+pub fn confine_process(roots: Arc<AutomationRoots>) -> bool {
+    PROCESS.set(roots).is_ok()
+}
+
+/// Puts the scope it replaced back when dropped (also when `f` panics).
+struct Restore(Option<Scope>);
+
+impl Drop for Restore {
+    fn drop(&mut self) {
+        let previous = self.0.take();
+        SCOPE.with(|s| *s.borrow_mut() = previous);
+    }
+}
+
+fn with_scope<T>(scope: Option<Scope>, f: impl FnOnce() -> T) -> T {
+    let _restore = Restore(SCOPE.with(|s| s.replace(scope)));
+    f()
+}
+
+/// Run `f` with `roots` in force on this thread (`None`: as things stand).
+pub fn confine<T>(roots: Option<&Arc<AutomationRoots>>, f: impl FnOnce() -> T) -> T {
+    match roots {
+        Some(r) => with_scope(Some(Scope::Confined(r.clone())), f),
+        None => f(),
+    }
+}
+
+/// Run `f` with no roots in force on this thread: what the person at the keyboard does, and the
+/// app's own folders.
+pub fn unconfined<T>(f: impl FnOnce() -> T) -> T {
+    with_scope(Some(Scope::Unconfined), f)
+}
+
+/// The roots in force on this thread, if any.
+pub fn current() -> Option<Arc<AutomationRoots>> {
+    match SCOPE.with(|s| s.borrow().clone()) {
+        Some(Scope::Confined(r)) => Some(r),
+        Some(Scope::Unconfined) => None,
+        None => PROCESS.get().cloned(),
+    }
+}
+
+/// `path` without Windows' `\\?\` prefix (which `canonicalize` adds), for people to read.
+fn plain(path: PathBuf) -> PathBuf {
+    if !cfg!(windows) {
+        return path;
+    }
+    let text = path.to_string_lossy();
+    if let Some(rest) = text.strip_prefix(r"\\?\UNC\") {
+        return PathBuf::from(format!(r"\\{rest}"));
+    }
+    match text.strip_prefix(r"\\?\") {
+        Some(rest) => PathBuf::from(rest),
+        None => path,
+    }
+}
+
+/// May `path` be read here? Always, without roots in force.
+pub fn check_read(path: &str) -> Result<(), String> {
+    current().map_or(Ok(()), |r| r.check(path, Access::Read))
+}
+
+/// May `path` be written here? Always, without roots in force.
+pub fn check_write(path: &str) -> Result<(), String> {
+    current().map_or(Ok(()), |r| r.check(path, Access::Write))
+}
+
+/// `path` made absolute with its links followed; for a path that doesn't exist (yet), its nearest
+/// existing folder's links followed and the rest appended.
+fn resolve(path: &str) -> Result<PathBuf, String> {
+    if path.is_empty() {
+        return Err("automation path rejected: path is empty".into());
+    }
+    // Checked as given: making `…\NUL` absolute gives the device path `\\.\NUL` on Windows.
+    if cfg!(windows) && Path::new(path).components().any(|c| matches!(c, Component::Normal(n) if is_device_name(&n.to_string_lossy()))) {
+        return Err(format!("automation path rejected: reserved device names are not allowed: {path}"));
+    }
+    let absolute = std::path::absolute(path).map_err(|e| format!("automation path rejected: cannot resolve {path}: {e}"))?;
+    // The names below the nearest existing folder, last first.
+    let mut missing: Vec<OsString> = vec![];
+    let mut at = absolute.as_path();
+    loop {
+        match std::fs::canonicalize(at) {
+            Ok(mut found) => {
+                found.extend(missing.iter().rev());
+                return Ok(found);
+            }
+            Err(e) => match std::fs::symlink_metadata(at) {
+                Ok(m) if m.file_type().is_symlink() => return Err(format!("automation path rejected: a link that leads nowhere: {path}")),
+                // There, yet its real path can't be had (no permission): nothing to compare.
+                Ok(_) => return Err(format!("automation path rejected: cannot resolve {path}: {e}")),
+                Err(e) if e.kind() == std::io::ErrorKind::NotFound => {}
+                Err(e) => return Err(format!("automation path rejected: cannot resolve {path}: {e}")),
+            },
+        }
+        let parent = at.parent();
+        match (at.components().next_back(), parent) {
+            (Some(Component::Normal(name)), Some(parent)) => {
+                missing.push(name.to_os_string());
+                at = parent;
+            }
+            (Some(Component::ParentDir), _) => {
+                return Err(format!("automation path rejected: parent traversal below a folder that doesn't exist: {path}"));
+            }
+            // Down to the root (or drive) and it doesn't exist either.
+            _ => {
+                let e = std::io::Error::from(std::io::ErrorKind::NotFound);
+                return Err(format!("automation path rejected: cannot resolve {path}: {e}"));
+            }
+        }
+    }
+}
+
+/// Is `path` (resolved) `root` or inside it, component by component (without regard to case on
+/// Windows, whose file systems ignore it)?
+fn inside(path: &Path, root: &Path) -> bool {
+    let mut path = path.components();
+    root.components().all(|r| path.next().is_some_and(|p| same_component(p, r)))
+}
+
+fn same_component(a: Component, b: Component) -> bool {
+    if a == b {
+        return true;
+    }
+    if !cfg!(windows) {
+        return false;
+    }
+    match (a.as_os_str().to_str(), b.as_os_str().to_str()) {
+        (Some(a), Some(b)) => a.to_lowercase() == b.to_lowercase(),
+        _ => false,
+    }
+}
+
+/// A Windows device name (`CON`, `NUL`, `COM1`… also with an extension), which names no file.
+fn is_device_name(component: &str) -> bool {
+    let stem = component.split('.').next().unwrap_or(component).trim_end_matches(' ').to_ascii_uppercase();
+    let numbered = |prefix: &str| stem.strip_prefix(prefix).is_some_and(|n| matches!(n, "1" | "2" | "3" | "4" | "5" | "6" | "7" | "8" | "9"));
+    matches!(stem.as_str(), "CON" | "PRN" | "AUX" | "NUL" | "CLOCK$" | "CONIN$" | "CONOUT$") || numbered("COM") || numbered("LPT")
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    /// A fresh folder holding `in` (read root), `out` (write root) and `outside`.
+    fn folders(name: &str) -> (PathBuf, Arc<AutomationRoots>) {
+        let base = std::env::temp_dir().join(format!("dc-file-access-{name}-{}", std::process::id()));
+        let _ = std::fs::remove_dir_all(&base);
+        for d in ["in/sub", "out", "outside", "in2"] {
+            std::fs::create_dir_all(base.join(d)).unwrap();
+        }
+        std::fs::write(base.join("in/a.deckcraft"), "x").unwrap();
+        std::fs::write(base.join("outside/secret.deckcraft"), "x").unwrap();
+        let roots = AutomationRoots::new(Some(&base.join("in")), Some(&base.join("out"))).unwrap().unwrap();
+        (base, roots)
+    }
+
+    fn s(p: PathBuf) -> String {
+        p.to_string_lossy().into_owned()
+    }
+
+    #[test]
+    fn paths_inside_the_roots_pass_and_others_dont() {
+        let (base, roots) = folders("inside");
+        assert_eq!(roots.check(&s(base.join("in/a.deckcraft")), Access::Read), Ok(()));
+        assert_eq!(roots.check(&s(base.join("in")), Access::Read), Ok(()), "the root itself");
+        assert_eq!(roots.check(&s(base.join("in/sub/new.deckcraft")), Access::Read), Ok(()), "missing files are checked by their folder");
+        assert_eq!(roots.check(&s(base.join("out/new/deeper/x.png")), Access::Write), Ok(()), "and by their nearest folder");
+        let e = roots.check(&s(base.join("outside/secret.deckcraft")), Access::Read).unwrap_err();
+        assert!(e.starts_with("automation path rejected: outside the read root"), "{e}");
+        // Read and write access are separate.
+        let e = roots.check(&s(base.join("in/a.deckcraft")), Access::Write).unwrap_err();
+        assert!(e.contains("outside the write root"), "{e}");
+        assert!(roots.check(&s(base.join("out/x.png")), Access::Read).unwrap_err().contains("outside the read root"));
+        let _ = std::fs::remove_dir_all(base);
+    }
+
+    #[test]
+    fn a_sibling_with_the_same_prefix_is_outside() {
+        let (base, roots) = folders("prefix");
+        std::fs::write(base.join("in2/b.deckcraft"), "x").unwrap();
+        assert!(roots.check(&s(base.join("in2/b.deckcraft")), Access::Read).is_err(), "in2 is not inside in");
+        assert!(roots.check(&format!("{}2/c.deckcraft", s(base.join("in"))), Access::Read).is_err());
+        let _ = std::fs::remove_dir_all(base);
+    }
+
+    #[test]
+    fn parent_traversal_is_resolved_or_refused() {
+        let (base, roots) = folders("dotdot");
+        let sep = std::path::MAIN_SEPARATOR;
+        let up = format!("{}{sep}..{sep}outside{sep}secret.deckcraft", s(base.join("in")));
+        assert!(roots.check(&up, Access::Read).unwrap_err().contains("outside the read root"), "`..` out of the root");
+        let back = format!("{}{sep}..{sep}a.deckcraft", s(base.join("in/sub")));
+        assert_eq!(roots.check(&back, Access::Read), Ok(()), "`..` that stays inside");
+        let missing = format!("{}{sep}nope{sep}..{sep}..{sep}outside{sep}x.deckcraft", s(base.join("out")));
+        let e = roots.check(&missing, Access::Write).unwrap_err();
+        // Windows resolves `..` by name first (so does opening the file there): then it's outside.
+        assert!(e.contains("parent traversal below a folder that doesn't exist") || e.contains("outside the write root"), "{e}");
+        let _ = std::fs::remove_dir_all(base);
+    }
+
+    #[test]
+    fn relative_paths_resolve_against_the_working_directory() {
+        let (base, roots) = folders("relative");
+        // The tests' working directory is the crate's folder: not inside the roots.
+        assert!(roots.check("a.deckcraft", Access::Read).unwrap_err().contains("outside the read root"));
+        assert!(roots.check("", Access::Read).unwrap_err().contains("path is empty"));
+        let _ = std::fs::remove_dir_all(base);
+    }
+
+    #[test]
+    fn a_missing_root_is_an_error_and_none_is_no_confinement() {
+        let (base, _) = folders("missing");
+        let e = AutomationRoots::new(Some(&base.join("nope")), None).unwrap_err();
+        assert!(e.starts_with("cannot open the automation read root"), "{e}");
+        let e = AutomationRoots::new(None, Some(&base.join("in/a.deckcraft"))).unwrap_err();
+        assert!(
+            e.starts_with("cannot open the automation write root")
+                && e.ends_with(&std::io::Error::from(std::io::ErrorKind::NotADirectory).to_string()),
+            "{e}"
+        );
+        assert!(AutomationRoots::new(Some(Path::new("")), None).unwrap_err().starts_with("cannot open the automation read root ``"));
+        assert!(AutomationRoots::new(None, None).unwrap().is_none());
+        // One root alone grants only its own access.
+        let read_only = AutomationRoots::new(Some(&base.join("in")), None).unwrap().unwrap();
+        let e = read_only.check(&s(base.join("in/x.deckcraft")), Access::Write).unwrap_err();
+        assert!(e.contains("write authority is absent"), "{e}");
+        let _ = std::fs::remove_dir_all(base);
+    }
+
+    #[test]
+    fn links_are_followed_before_comparing() {
+        let (base, roots) = folders("links");
+        #[cfg(unix)]
+        let made = |target: &Path, link: &Path| std::os::unix::fs::symlink(target, link).is_ok();
+        #[cfg(windows)]
+        let made = |target: &Path, link: &Path| {
+            let made =
+                if target.is_dir() { std::os::windows::fs::symlink_dir(target, link) } else { std::os::windows::fs::symlink_file(target, link) };
+            made.is_ok()
+        };
+        #[cfg(not(any(unix, windows)))]
+        let made = |_: &Path, _: &Path| false;
+        // Windows needs Developer Mode or elevation to make links: nothing to test without them.
+        if !made(&base.join("outside/secret.deckcraft"), &base.join("in/leak.deckcraft")) {
+            eprintln!("skipped: symbolic links can't be made here");
+            let _ = std::fs::remove_dir_all(base);
+            return;
+        }
+        assert!(roots.check(&s(base.join("in/leak.deckcraft")), Access::Read).unwrap_err().contains("outside the read root"), "a file link out");
+        assert!(made(&base.join("outside"), &base.join("out/away")));
+        let e = roots.check(&s(base.join("out/away/new.png")), Access::Write).unwrap_err();
+        assert!(e.contains("outside the write root"), "a folder link out: {e}");
+        assert!(made(&base.join("outside/gone.deckcraft"), &base.join("out/dangling.png")));
+        let e = roots.check(&s(base.join("out/dangling.png")), Access::Write).unwrap_err();
+        assert!(e.contains("a link that leads nowhere"), "writing would create the file outside: {e}");
+        // A link to a folder inside the root stays inside.
+        assert!(made(&base.join("in/sub"), &base.join("in/alias")));
+        assert_eq!(roots.check(&s(base.join("in/alias/x.deckcraft")), Access::Read), Ok(()));
+        // A root given through a link is the folder it leads to.
+        assert!(made(&base.join("in"), &base.join("in-link")));
+        let linked = AutomationRoots::new(Some(&base.join("in-link")), None).unwrap().unwrap();
+        assert_eq!(linked.check(&s(base.join("in/a.deckcraft")), Access::Read), Ok(()));
+        let _ = std::fs::remove_dir_all(base);
+    }
+
+    #[cfg(windows)]
+    #[test]
+    fn windows_ignores_case_and_refuses_devices() {
+        let (base, roots) = folders("case");
+        let upper = s(base.join("IN/a.deckcraft"));
+        assert_eq!(roots.check(&upper, Access::Read), Ok(()), "{upper}");
+        assert_eq!(roots.check(&s(base.join("In/Sub/New.deckcraft")), Access::Read), Ok(()));
+        let e = roots.check(&s(base.join("out/NUL")), Access::Write).unwrap_err();
+        assert!(e.contains("reserved device names"), "{e}");
+        assert!(roots.check(&s(base.join("out/com1.txt")), Access::Write).is_err());
+        assert_eq!(roots.check(&s(base.join("out/console.txt")), Access::Write), Ok(()));
+        let _ = std::fs::remove_dir_all(base);
+    }
+
+    #[test]
+    fn scopes_nest_and_stay_on_their_thread() {
+        let (base, roots) = folders("scopes");
+        let outside = s(base.join("outside/secret.deckcraft"));
+        assert_eq!(check_read(&outside), Ok(()), "nothing is confined by default");
+        confine(Some(&roots), || {
+            assert!(check_read(&outside).is_err());
+            assert_eq!(unconfined(|| check_read(&outside)), Ok(()));
+            assert!(check_read(&outside).is_err(), "restored after unconfined");
+            let o = outside.clone();
+            let there = std::thread::spawn(move || check_read(&o).is_ok()).join().unwrap();
+            assert!(there, "another thread is not confined by this thread's scope");
+        });
+        assert_eq!(check_read(&outside), Ok(()), "restored after confine");
+        let r = std::panic::catch_unwind(|| confine(Some(&roots), || panic!("boom")));
+        assert!(r.is_err());
+        assert_eq!(check_read(&outside), Ok(()), "restored after a panic");
+        assert_eq!(confine(None, || check_read(&outside)), Ok(()));
+        let _ = std::fs::remove_dir_all(base);
+    }
+
+    #[test]
+    fn device_names() {
+        for d in ["CON", "nul", "Com1", "LPT9.txt", "aux.deckcraft", "NUL "] {
+            assert!(is_device_name(d), "{d}");
+        }
+        for f in ["console", "com10", "COM0", "lpt", "a.deckcraft", "nul-x"] {
+            assert!(!is_device_name(f), "{f}");
+        }
+    }
+
+    /// Every file a command reads or writes by path goes through `io` (`read_file`,
+    /// `write_file`), which check the roots. Engine code that reaches for `std::fs` itself would
+    /// bypass them, so none may: every file under `src/` (commands, `lib.rs`, `guard.rs`...)
+    /// except `io.rs`, this module, `recovery.rs` (the recovery folder is set by the host
+    /// application, never by a command's path, and a headless session has none) and the test
+    /// files.
+    #[test]
+    fn commands_do_not_touch_the_file_system_themselves() {
+        fn walk(dir: &Path, files: &mut Vec<PathBuf>) {
+            for entry in std::fs::read_dir(dir).unwrap() {
+                let path = entry.unwrap().path();
+                if path.is_dir() {
+                    walk(&path, files);
+                } else if path.extension().is_some_and(|e| e == "rs") {
+                    files.push(path);
+                }
+            }
+        }
+        let src = Path::new(env!("CARGO_MANIFEST_DIR")).join("src");
+        let mut files = vec![];
+        walk(&src, &mut files);
+        assert!(files.iter().any(|f| f.ends_with("lib.rs")) && files.iter().any(|f| f.ends_with("cmd/file.rs")), "{files:?}");
+        let mut offenders = vec![];
+        for path in files {
+            let name = path.file_name().and_then(|n| n.to_str()).unwrap_or("");
+            // `io` and this module are the checked gateway; `tests*.rs` are test-only modules.
+            // `recovery` and `spell` touch only the app's own folders (AutoRecover files, the
+            // system and user spelling dictionaries), never a path a command names.
+            if path.parent() == Some(src.as_path()) && matches!(name, "io.rs" | "file_access.rs" | "recovery.rs" | "spell.rs")
+                || name.starts_with("tests")
+            {
+                continue;
+            }
+            let text = std::fs::read_to_string(&path).unwrap();
+            // Test modules (which build their own fixtures) come last in each file.
+            let code = text.split("#[cfg(test)]").next().unwrap_or("");
+            for (n, line) in code.lines().enumerate() {
+                let line = line.trim_start();
+                let touches = ["std::fs", "File::open", "File::create", "OpenOptions"].iter().any(|w| line.contains(w));
+                if !line.starts_with("//") && touches {
+                    offenders.push(format!("{}:{}: {line}", path.display(), n + 1));
+                }
+            }
+        }
+        assert!(offenders.is_empty(), "use crate::io::{{read_file, write_file}}: {offenders:#?}");
+    }
+}

crates/engine/src/io.rs

@@ -0,0 +1,69 @@
+//! Reading and writing the files a command names by path.
+//!
+//! Every such read and write goes through [`read_file`] and [`write_file`], so the automation
+//! roots ([`crate::file_access`]) are checked in one place. A command module that called
+//! `std::fs` itself would bypass them; a test in `file_access` keeps that from happening.
+
+/// The bytes of the file at `path`, inside the automation read root when there is one.
+#[cfg(not(target_arch = "wasm32"))]
+pub fn read_file(path: &str) -> Result<Vec<u8>, String> {
+    crate::file_access::check_read(path)?;
+    std::fs::read(path).map_err(|e| format!("{path}: {e}"))
+}
+
+#[cfg(target_arch = "wasm32")]
+pub fn read_file(path: &str) -> Result<Vec<u8>, String> {
+    Err(format!("{path}: files are opened through the browser on the web"))
+}
+
+/// Write `bytes` to the file at `path`, inside the automation write root when there is one.
+///
+/// The bytes go to a temporary sibling first and are renamed over `path`, so a failed save never
+/// truncates the old file. The sibling is in the same folder, so it is inside the root whenever
+/// `path` is.
+#[cfg(not(target_arch = "wasm32"))]
+pub fn write_file(path: &str, bytes: &[u8]) -> Result<(), String> {
+    use std::io::Write;
+    use std::sync::atomic::{AtomicU64, Ordering};
+    static COUNTER: AtomicU64 = AtomicU64::new(0);
+    crate::file_access::check_write(path)?;
+    let err = |e: std::io::Error| format!("{path}: {e}");
+    // A uniquely named temporary sibling, created exclusively (never following or reusing an
+    // existing file or symlink), is renamed over the destination: concurrent saves never share
+    // temporary bytes.
+    let mut attempts = 0;
+    let (tmp, mut file) = loop {
+        let tmp = format!("{path}.{}.{}.saving", std::process::id(), COUNTER.fetch_add(1, Ordering::Relaxed));
+        match std::fs::OpenOptions::new().write(true).create_new(true).open(&tmp) {
+            Ok(f) => break (tmp, f),
+            Err(e) if e.kind() == std::io::ErrorKind::AlreadyExists && attempts < 16 => attempts += 1,
+            Err(e) => return Err(err(e)),
+        }
+    };
+    let written = file.write_all(bytes).and_then(|()| file.sync_all());
+    drop(file);
+    let result = written.and_then(|()| std::fs::rename(&tmp, path));
+    if let Err(e) = result {
+        let _ = std::fs::remove_file(&tmp);
+        return Err(err(e));
+    }
+    Ok(())
+}
+
+#[cfg(target_arch = "wasm32")]
+pub fn write_file(path: &str, _bytes: &[u8]) -> Result<(), String> {
+    Err(format!("{path}: saving to a path is not available in the browser"))
+}
+
+/// The size in bytes of the file at `path`; `None` when it can't be read (or is outside the
+/// automation read root, so File › Info doesn't reveal files the agent may not read).
+#[cfg(not(target_arch = "wasm32"))]
+pub fn file_len(path: &str) -> Option<u64> {
+    crate::file_access::check_read(path).ok()?;
+    std::fs::metadata(path).ok().map(|m| m.len())
+}
+
+#[cfg(target_arch = "wasm32")]
+pub fn file_len(_path: &str) -> Option<u64> {
+    None
+}

crates/engine/src/lib.rs

@@ -11,11 +11,13 @@ pub mod cmd;
 pub mod compare;
 pub mod connect;
 pub mod drawtable;
+pub mod file_access;
 pub mod fonts;
 pub mod gif_export;
 pub mod guard;
 pub mod icons;
 pub mod inkshape;
+pub mod io;
 pub mod keys;
 pub mod links;
 pub mod recovery;

crates/engine/src/tests.rs

@@ -867,6 +867,8 @@ fn right_to_left_paragraphs() {
     let mut s = session();
     let title = s.doc().unwrap().current_slide().unwrap().shapes[0].id.0;
     s.execute("text.edit", &json!({"id": title})).unwrap();
+    // Explicitly left-to-right first, so typing Arabic doesn't already turn it right-to-left (#169).
+    s.execute("format.rtl", &json!({"on": false})).unwrap();
     s.execute("text.insert", &json!({"text": "سنة 2024 (Retrait) فقط"})).unwrap();
     s.execute("format.rtl", &json!({})).unwrap();
     let para = |s: &Session| s.doc().unwrap().current_slide().unwrap().shapes[0].text.as_ref().unwrap().paragraphs[0].props.clone();
@@ -887,6 +889,61 @@ fn right_to_left_paragraphs() {
     assert_eq!(para(&s).rtl, Some(true));
 }
 
+#[test]
+fn typing_kurdish_or_arabic_auto_detects_rtl_and_advances_caret_smoothly() {
+    let mut s = session();
+    let title = s.doc().unwrap().current_slide().unwrap().shapes[0].id.0;
+    s.execute("text.edit", &json!({"id": title})).unwrap();
+
+    let mut first_x = None;
+    let mut last_x = 0.0;
+
+    // Type Kurdish sentence character-by-character: "من ناوم هێڤاره"
+    for ch in ["م", "ن", " ", "ن", "ا", "و", "م", " ", "ه", "ێ", "ڤ", "ا", "ر", "ه"] {
+        s.execute("text.insert", &json!({"text": ch})).unwrap();
+        let st = s.doc().unwrap();
+        let t = st.selection.text.as_ref().unwrap();
+        let l = super::cmd::text::layout_for(st, t).unwrap();
+        let (cx, ..) = l.caret(deckcraft_text::Pos { para: t.caret.0, ch: t.caret.1 }).unwrap();
+
+        if first_x.is_none() {
+            first_x = Some(cx);
+        }
+        last_x = cx;
+
+        // The title is centred: the caret must NOT jump back to the left margin (~7.2 pt).
+        assert!(cx > 100.0, "caret should not jump to left margin: {cx}");
+    }
+
+    // Caret advances leftwards overall as text is appended
+    assert!(last_x < first_x.unwrap(), "caret should advance leftwards: last={last_x} first={:?}", first_x);
+    let para = s.doc().unwrap().current_slide().unwrap().shapes[0].text.as_ref().unwrap().paragraphs[0].props.clone();
+    assert_eq!(para.rtl, Some(true), "auto-detected as RTL");
+    assert_eq!(para.align, None, "the title keeps the alignment it inherits");
+
+    // A text box inherits the deck's default (left) alignment, which it keeps too.
+    s.execute("text.exit", &json!({})).ok();
+    let id = s.execute("insert.textBox", &json!({"rect": [10, 10, 300, 100], "text": ""})).unwrap()["id"].as_u64().unwrap();
+    s.execute("text.edit", &json!({"id": id})).unwrap();
+    s.execute("text.insert", &json!({"text": "مرحبا"})).unwrap();
+    let st = s.doc().unwrap();
+    let sh = st.shape(deckcraft_model::ShapeId(id as u32)).unwrap();
+    let para = sh.text.as_ref().unwrap().paragraphs[0].props.clone();
+    assert_eq!(para.rtl, Some(true));
+    assert_eq!(para.align, None, "the text box keeps the alignment it inherits");
+}
+
+#[test]
+fn explicit_ltr_override_is_preserved_when_typing_rtl() {
+    let mut s = session();
+    let title = s.doc().unwrap().current_slide().unwrap().shapes[0].id.0;
+    s.execute("text.edit", &json!({"id": title})).unwrap();
+    s.execute("format.rtl", &json!({"on": false})).unwrap();
+    s.execute("text.insert", &json!({"text": "مرحبا"})).unwrap();
+    let para = s.doc().unwrap().current_slide().unwrap().shapes[0].text.as_ref().unwrap().paragraphs[0].props.clone();
+    assert_eq!(para.rtl, Some(false), "user explicit LTR is preserved");
+}
+
 #[test]
 fn header_footer_fixed_date_is_the_slides_own_text() {
     use deckcraft_model::text::RunKind;
@@ -3117,6 +3174,37 @@ fn language_marks_text_and_no_proof_and_repeats_are_reported() {
     assert!(s.execute("format.language", &json!({"lang": "en US!"})).is_err());
 }
 
+#[test]
+fn the_caret_takes_the_colour_of_the_text() {
+    let caret = |theme: &str| {
+        let mut s = session();
+        s.execute("design.theme", &json!({"name": theme})).unwrap();
+        let title = s.doc().unwrap().current_slide().unwrap().shapes[0].id.0;
+        s.execute("text.edit", &json!({"id": title})).unwrap();
+        let st = s.doc().unwrap();
+        let empty = cmd::text::caret_color(st, &st.selection.text.clone().unwrap()).unwrap();
+        s.execute("text.insert", &json!({"text": "Typed"})).unwrap();
+        let st = s.doc().unwrap();
+        assert_eq!(cmd::text::caret_color(st, &st.selection.text.clone().unwrap()), Some(empty));
+        empty
+    };
+    // Dark text on the light theme, light text on the dark one: never black on a dark slide.
+    let (light, dark) = (caret("DeckCraft"), caret("Nocturne"));
+    assert!(light.r < 0x60 && light.g < 0x60 && light.b < 0x60, "{light:?}");
+    assert!(dark.r > 0xC0 && dark.g > 0xC0 && dark.b > 0xC0, "{dark:?}");
+    // Text set to red gets a red caret.
+    let mut s = session();
+    let title = s.doc().unwrap().current_slide().unwrap().shapes[0].id.0;
+    s.execute("text.edit", &json!({"id": title})).unwrap();
+    s.execute("text.insert", &json!({"text": "Red"})).unwrap();
+    s.execute("text.selectAll", &json!({})).unwrap();
+    s.execute("format.color", &json!({"color": "#FF0000"})).unwrap();
+    s.execute("text.move", &json!({"to": "end"})).unwrap();
+    let st = s.doc().unwrap();
+    let red = cmd::text::caret_color(st, &st.selection.text.clone().unwrap()).unwrap();
+    assert_eq!((red.r, red.g, red.b), (0xFF, 0, 0));
+}
+
 /// Smooth Corners (#286): a rounded rectangle becomes a squircle outline that survives PPTX.
 #[test]
 fn smooth_corners_makes_a_squircle_outline() {

crates/mcp/src/headless.rs

@@ -1,6 +1,9 @@
 //! An in-process engine session that answers the engine-level control-channel methods itself.
 
 use deckcraft_engine::{Mods, PointerEvent, PointerKind, Session, ToolKind};
+use std::sync::Arc;
+
+use deckcraft_engine::file_access::{self, AutomationRoots};
 use serde_json::{Value, json};
 
 use crate::backend::Backend;
@@ -8,6 +11,7 @@ use crate::backend::Backend;
 /// Headless backend: a [`Session`] rendering slides on the CPU.
 pub struct Headless {
     pub session: Session,
+    roots: Option<Arc<AutomationRoots>>,
 }
 
 impl Default for Headless {
@@ -59,12 +63,19 @@ pub fn tool_kind(name: &str, preset: Option<&str>) -> Option<ToolKind> {
 
 impl Headless {
     pub fn new() -> Self {
-        Self { session: Session::new() }
+        Self { session: Session::new(), roots: None }
     }
 
     /// A session with a fresh presentation.
     pub fn with_document() -> Self {
-        Self { session: Session::with_new() }
+        Self { session: Session::with_new(), roots: None }
+    }
+
+    /// Confine every file the session's commands read and write to `roots`
+    /// (`deckcraft-cli mcp --automation-read-root … --automation-write-root …`).
+    pub fn with_automation_roots(mut self, roots: Option<Arc<AutomationRoots>>) -> Self {
+        self.roots = roots;
+        self
     }
 
     fn exec(&mut self, id: &str, params: &Value) -> Result<Value, String> {
@@ -111,7 +122,7 @@ impl Headless {
         );
         let png = img.to_png_at(deckcraft_engine::render::dpi_for_scale(scale));
         if let Some(path) = s(p, "path") {
-            std::fs::write(path, &png).map_err(|e| format!("{path}: {e}"))?;
+            deckcraft_engine::io::write_file(path, &png)?;
             return Ok(json!({"path": path, "width": img.width, "height": img.height}));
         }
         Ok(json!({"png": deckcraft_engine::cmd::base64_encode(&png), "width": img.width, "height": img.height, "slide": i}))
@@ -120,6 +131,19 @@ impl Headless {
 
 impl Backend for Headless {
     fn call(&mut self, method: &str, params: Value) -> Result<Value, String> {
+        let roots = self.roots.clone();
+        file_access::confine(roots.as_ref(), || self.answer(method, params))
+    }
+    fn has_ui(&self) -> bool {
+        false
+    }
+    fn describe(&self) -> String {
+        "headless (in-process engine; no window)".into()
+    }
+}
+
+impl Headless {
+    fn answer(&mut self, method: &str, params: Value) -> Result<Value, String> {
         let p = &params;
         match method {
             "engine.execute" | "command" | "ui.menu.invoke" => {
@@ -153,10 +177,4 @@ impl Backend for Headless {
             other => Err(format!("unknown method `{other}`")),
         }
     }
-    fn has_ui(&self) -> bool {
-        false
-    }
-    fn describe(&self) -> String {
-        "headless (in-process engine; no window)".into()
-    }
 }

crates/mcp/tests/automation_roots.rs

@@ -0,0 +1,225 @@
+//! `deckcraft-cli mcp --automation-read-root <dir> --automation-write-root <dir>`: through the MCP
+//! protocol, files open and load only from inside the read root and are saved and exported only
+//! inside the write root. Paths that leave a root (`..`, another folder, a sibling with the same
+//! prefix, a link) are refused, and nothing is written outside.
+// Integration tests: unwrapping and panicking on failure is fine here, unlike in shipped code (AGENTS.md).
+#![allow(clippy::unwrap_used, clippy::expect_used, clippy::panic)]
+
+use std::path::{Path, PathBuf};
+
+use deckcraft_engine::file_access::AutomationRoots;
+use deckcraft_mcp::{Headless, Server};
+use serde_json::{Value, json};
+
+/// A 1x1 PNG, so `insert_picture` has something real to read.
+const PNG: &[u8] = &[
+    0x89, 0x50, 0x4e, 0x47, 0x0d, 0x0a, 0x1a, 0x0a, 0x00, 0x00, 0x00, 0x0d, 0x49, 0x48, 0x44, 0x52, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x01,
+    0x08, 0x06, 0x00, 0x00, 0x00, 0x1f, 0x15, 0xc4, 0x89, 0x00, 0x00, 0x00, 0x0d, 0x49, 0x44, 0x41, 0x54, 0x78, 0x9c, 0x63, 0xf8, 0xcf, 0xc0, 0xf0,
+    0x1f, 0x00, 0x05, 0x00, 0x01, 0xff, 0x89, 0x99, 0x3d, 0x1d, 0x00, 0x00, 0x00, 0x00, 0x49, 0x45, 0x4e, 0x44, 0xae, 0x42, 0x60, 0x82,
+];
+
+/// A fresh folder holding `in` (the read root, with `a.txt` and `pic.png`), `out` (the write root),
+/// `outside` (with `secret.txt` and `pic.png`) and `in2`, and a server confined to `in` and `out`
+/// (either may be left out). The server starts with a new presentation.
+fn confined(tag: &str, read: bool, write: bool) -> (Server, PathBuf) {
+    let base = std::env::temp_dir().join(format!("dc-mcp-roots-{tag}-{}", std::process::id()));
+    let _ = std::fs::remove_dir_all(&base);
+    for d in ["in", "out", "outside", "in2"] {
+        std::fs::create_dir_all(base.join(d)).unwrap();
+    }
+    std::fs::write(base.join("in/a.txt"), "Inside text").unwrap();
+    std::fs::write(base.join("in/pic.png"), PNG).unwrap();
+    std::fs::write(base.join("outside/secret.txt"), "TOP SECRET").unwrap();
+    std::fs::write(base.join("outside/pic.png"), PNG).unwrap();
+    std::fs::write(base.join("in2/c.txt"), "Sibling").unwrap();
+    let (in_dir, out_dir) = (base.join("in"), base.join("out"));
+    let roots = AutomationRoots::new(read.then_some(in_dir.as_path()), write.then_some(out_dir.as_path())).unwrap();
+    let mut server = Server::new(Box::new(Headless::with_document().with_automation_roots(roots)));
+    ok(&mut server, "new_presentation", json!({}));
+    (server, base)
+}
+
+fn s(p: &Path) -> String {
+    p.to_string_lossy().into_owned()
+}
+
+/// `tools/call` -> (isError, the first text block).
+fn call(server: &mut Server, name: &str, args: Value) -> (bool, String) {
+    let line = json!({"jsonrpc": "2.0", "id": 1, "method": "tools/call", "params": {"name": name, "arguments": args}}).to_string();
+    let reply: Value = serde_json::from_str(&server.handle_line(&line).unwrap()).unwrap();
+    let result = &reply["result"];
+    let text = result["content"].as_array().unwrap().iter().find_map(|c| c["text"].as_str()).unwrap_or_default().to_string();
+    (result["isError"] == true, text)
+}
+
+fn ok(server: &mut Server, name: &str, args: Value) -> String {
+    let (error, text) = call(server, name, args.clone());
+    assert!(!error, "{name} {args}: {text}");
+    text
+}
+
+fn refused(server: &mut Server, name: &str, args: Value, why: &str) {
+    let (error, text) = call(server, name, args.clone());
+    assert!(error && text.contains(why), "{name} {args} should be refused ({why}): {text}");
+}
+
+fn run(server: &mut Server, command: &str, params: Value) -> (bool, String) {
+    call(server, "run_command", json!({"command": command, "params": params}))
+}
+
+/// Everything the open presentation says, as one string.
+fn deck_text(server: &mut Server) -> String {
+    format!("{} {}", ok(server, "inspect_document", json!({})), ok(server, "inspect_slide", json!({})))
+}
+
+#[test]
+fn presentations_open_only_from_inside_the_read_root() {
+    let (mut server, base) = confined("open", true, true);
+    let sep = std::path::MAIN_SEPARATOR;
+    ok(&mut server, "open_presentation", json!({"path": s(&base.join("in/a.txt"))}));
+    assert!(deck_text(&mut server).contains("Inside text"));
+
+    refused(&mut server, "open_presentation", json!({"path": s(&base.join("outside/secret.txt"))}), "outside the read root");
+    refused(
+        &mut server,
+        "open_presentation",
+        json!({"path": format!("{}{sep}..{sep}outside{sep}secret.txt", s(&base.join("in")))}),
+        "outside the read root",
+    );
+    refused(&mut server, "open_presentation", json!({"path": s(&base.join("in2/c.txt"))}), "outside the read root");
+    // The write root isn't readable: the two kinds of access are separate.
+    std::fs::write(base.join("out/d.txt"), "d").unwrap();
+    refused(&mut server, "open_presentation", json!({"path": s(&base.join("out/d.txt"))}), "outside the read root");
+    // The same through the engine command and the control-channel method.
+    let (error, text) = run(&mut server, "file.open", json!({"path": s(&base.join("outside/secret.txt"))}));
+    assert!(error && text.contains("outside the read root"), "{text}");
+    refused(&mut server, "call_app", json!({"method": "app.open", "params": {"path": s(&base.join("outside/secret.txt"))}}), "outside the read root");
+    // Nothing from the refused files reached the deck.
+    let text = deck_text(&mut server);
+    assert!(!text.contains("TOP SECRET") && !text.contains("Sibling"), "{text}");
+    assert!(text.contains("Inside text"), "the refused opens left the deck it had: {text}");
+    let _ = std::fs::remove_dir_all(base);
+}
+
+#[test]
+fn pictures_media_and_other_path_reads_are_confined() {
+    let (mut server, base) = confined("media", true, true);
+    ok(&mut server, "insert_picture", json!({"path": s(&base.join("in/pic.png"))}));
+    let before = ok(&mut server, "inspect_slide", json!({}));
+    refused(&mut server, "insert_picture", json!({"path": s(&base.join("outside/pic.png"))}), "outside the read root");
+    for command in ["insert.audio", "insert.video", "insert.picture", "picture.change"] {
+        let (error, text) = run(&mut server, command, json!({"path": s(&base.join("outside/pic.png"))}));
+        assert!(error && text.contains("outside the read root"), "{command}: {text}");
+    }
+    assert_eq!(ok(&mut server, "inspect_slide", json!({})), before, "refused reads change nothing");
+
+    // Media inside the root gets as far as being read: a refusal there would name the root.
+    for command in ["insert.audio", "insert.video"] {
+        let (_, text) = run(&mut server, command, json!({"path": s(&base.join("in/pic.png"))}));
+        assert!(!text.contains("automation"), "{command}: {text}");
+    }
+    let _ = std::fs::remove_dir_all(base);
+}
+
+#[test]
+fn every_writing_command_is_refused_outside_the_write_root() {
+    let (mut server, base) = confined("write", true, true);
+    let outside = |name: &str| s(&base.join("outside").join(name));
+    let inside = |name: &str| s(&base.join("out").join(name));
+    ok(&mut server, "add_slide", json!({"title": "Second"}));
+
+    refused(&mut server, "save_presentation", json!({"path": outside("x.deckcraft")}), "outside the write root");
+    refused(&mut server, "export", json!({"path": outside("x.pptx")}), "outside the write root");
+    refused(&mut server, "export", json!({"path": outside("x.pdf")}), "outside the write root");
+    refused(&mut server, "export", json!({"path": outside("x.png")}), "outside the write root");
+    refused(&mut server, "export", json!({"path": outside("x.txt")}), "outside the write root");
+    refused(&mut server, "export", json!({"path": outside("all.png"), "all": true}), "outside the write root");
+    refused(&mut server, "call_app", json!({"method": "ui.render", "params": {"path": outside("r.png")}}), "outside the write root");
+    refused(&mut server, "call_app", json!({"method": "app.save", "params": {"path": outside("y.deckcraft")}}), "outside the write root");
+    refused(&mut server, "call_app", json!({"method": "app.export", "params": {"path": outside("y.pdf")}}), "outside the write root");
+    for command in ["file.save", "file.saveAs", "file.export"] {
+        let (error, text) = run(&mut server, command, json!({"path": outside("z.deckcraft")}));
+        assert!(error && text.contains("outside the write root"), "{command}: {text}");
+    }
+    // A sibling folder with the same prefix, and `..` out of the root.
+    refused(&mut server, "save_presentation", json!({"path": s(&base.join("out2/x.deckcraft"))}), "outside the write root");
+    let sep = std::path::MAIN_SEPARATOR;
+    refused(
+        &mut server,
+        "save_presentation",
+        json!({"path": format!("{}{sep}..{sep}outside{sep}x.deckcraft", s(&base.join("out")))}),
+        "outside the write root",
+    );
+    // The read root isn't writable.
+    refused(&mut server, "save_presentation", json!({"path": s(&base.join("in/x.deckcraft"))}), "outside the write root");
+
+    let leftovers: Vec<_> = std::fs::read_dir(base.join("outside")).unwrap().map(|e| e.unwrap().file_name()).collect();
+    assert_eq!(leftovers.len(), 2, "nothing was written beside secret.txt and pic.png: {leftovers:?}");
+    assert!(!base.join("out2").exists() && !base.join("in/x.deckcraft").exists());
+
+    // Inside the write root all of it works.
+    ok(&mut server, "save_presentation", json!({"path": inside("x.deckcraft")}));
+    ok(&mut server, "export", json!({"path": inside("x.pptx")}));
+    ok(&mut server, "export", json!({"path": inside("x.pdf")}));
+    ok(&mut server, "export", json!({"path": inside("all.png"), "all": true}));
+    ok(&mut server, "call_app", json!({"method": "ui.render", "params": {"path": inside("r.png")}}));
+    for f in ["x.deckcraft", "x.pptx", "x.pdf", "all1.png", "all2.png", "r.png"] {
+        assert!(base.join("out").join(f).exists(), "{f}");
+    }
+    let temporaries: Vec<_> = std::fs::read_dir(base.join("out"))
+        .unwrap()
+        .filter_map(|e| e.ok())
+        .filter(|e| e.file_name().to_string_lossy().ends_with(".saving"))
+        .collect();
+    assert!(temporaries.is_empty(), "the temporary file is renamed away");
+    let _ = std::fs::remove_dir_all(base);
+}
+
+#[test]
+fn one_root_grants_only_its_own_access() {
+    let (mut read_only, base) = confined("read-only", true, false);
+    ok(&mut read_only, "open_presentation", json!({"path": s(&base.join("in/a.txt"))}));
+    refused(&mut read_only, "save_presentation", json!({"path": s(&base.join("out/x.deckcraft"))}), "write authority is absent");
+    refused(&mut read_only, "export", json!({"path": s(&base.join("out/x.pdf"))}), "write authority is absent");
+    refused(&mut read_only, "call_app", json!({"method": "ui.render", "params": {"path": s(&base.join("out/r.png"))}}), "write authority is absent");
+    // Calls that return bytes instead of writing a path keep working.
+    let (error, _) = call(&mut read_only, "render_slide", json!({"scale": 0.25}));
+    assert!(!error);
+    assert!(std::fs::read_dir(base.join("out")).unwrap().next().is_none());
+    let _ = std::fs::remove_dir_all(base);
+
+    let (mut write_only, base) = confined("write-only", false, true);
+    refused(&mut write_only, "open_presentation", json!({"path": s(&base.join("in/a.txt"))}), "read authority is absent");
+    refused(&mut write_only, "insert_picture", json!({"path": s(&base.join("in/pic.png"))}), "read authority is absent");
+    ok(&mut write_only, "save_presentation", json!({"path": s(&base.join("out/x.deckcraft"))}));
+    assert!(base.join("out/x.deckcraft").exists());
+    let _ = std::fs::remove_dir_all(base);
+}
+
+#[cfg(unix)]
+#[test]
+fn links_out_of_a_root_are_refused() {
+    let (mut server, base) = confined("links", true, true);
+    std::os::unix::fs::symlink(base.join("outside/secret.txt"), base.join("in/leak.txt")).unwrap();
+    std::os::unix::fs::symlink(base.join("outside"), base.join("out/away")).unwrap();
+    std::os::unix::fs::symlink(base.join("outside/gone.deckcraft"), base.join("out/dangling.deckcraft")).unwrap();
+    refused(&mut server, "open_presentation", json!({"path": s(&base.join("in/leak.txt"))}), "outside the read root");
+    refused(&mut server, "save_presentation", json!({"path": s(&base.join("out/away/x.deckcraft"))}), "outside the write root");
+    refused(&mut server, "save_presentation", json!({"path": s(&base.join("out/dangling.deckcraft"))}), "a link that leads nowhere");
+    assert!(!base.join("outside/x.deckcraft").exists() && !base.join("outside/gone.deckcraft").exists());
+    assert!(!deck_text(&mut server).contains("TOP SECRET"));
+    let _ = std::fs::remove_dir_all(base);
+}
+
+#[test]
+fn without_roots_nothing_is_confined() {
+    let base = std::env::temp_dir().join(format!("dc-mcp-roots-none-{}", std::process::id()));
+    let _ = std::fs::remove_dir_all(&base);
+    std::fs::create_dir_all(&base).unwrap();
+    std::fs::write(base.join("a.txt"), "Anywhere").unwrap();
+    let mut server = Server::new(Box::new(Headless::with_document().with_automation_roots(AutomationRoots::new(None, None).unwrap())));
+    ok(&mut server, "open_presentation", json!({"path": s(&base.join("a.txt"))}));
+    ok(&mut server, "save_presentation", json!({"path": s(&base.join("b.deckcraft"))}));
+    assert!(base.join("b.deckcraft").exists());
+    let _ = std::fs::remove_dir_all(base);
+}

crates/model/src/bidi.rs

@@ -0,0 +1,81 @@
+//! Bidirectional text helpers (UAX #9).
+//!
+//! Follows Unicode Bidirectional Algorithm (UAX #9 rules P2 and P3) for paragraph
+//! base direction auto-detection.
+
+/// Does the first strong directional character in `text` belong to a right-to-left script?
+///
+/// Follows UAX #9 rules P2 and P3: characters with strong bidirectional class AL or R
+/// (Arabic, Hebrew, Syriac, Thaana…) give `true`; strong L characters (Latin, Greek,
+/// Cyrillic, CJK…) give `false`. Neutral, weak, and whitespace characters are skipped.
+pub fn first_strong_is_rtl(text: &str) -> bool {
+    for c in text.chars() {
+        if c == '\u{200F}' {
+            // Right-to-Left Mark (RLM)
+            return true;
+        }
+        if c == '\u{200E}' {
+            // Left-to-Right Mark (LRM)
+            return false;
+        }
+        if c.is_alphabetic() {
+            return is_rtl_script(c);
+        }
+    }
+    false
+}
+
+/// Helper checking if a char belongs to standard RTL Unicode blocks.
+pub fn is_rtl_script(c: char) -> bool {
+    matches!(
+        c,
+        '\u{0590}'..='\u{05FF}' // Hebrew
+        | '\u{0600}'..='\u{06FF}' // Arabic
+        | '\u{0700}'..='\u{074F}' // Syriac
+        | '\u{0750}'..='\u{077F}' // Arabic Supplement
+        | '\u{0780}'..='\u{07BF}' // Thaana
+        | '\u{0870}'..='\u{089F}' // Arabic Extended-B
+        | '\u{08A0}'..='\u{08FF}' // Arabic Extended-A
+        | '\u{FB1D}'..='\u{FB4F}' // Hebrew Presentation Forms
+        | '\u{FB50}'..='\u{FDFF}' // Arabic Presentation Forms-A
+        | '\u{FE70}'..='\u{FEFE}' // Arabic Presentation Forms-B
+    )
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn detects_arabic_and_kurdish() {
+        assert!(first_strong_is_rtl("مرحبا"));
+        assert!(first_strong_is_rtl("من ناوم هێڤاره"));
+        assert!(first_strong_is_rtl("سلام"));
+    }
+
+    #[test]
+    fn detects_hebrew() {
+        assert!(first_strong_is_rtl("שלום"));
+    }
+
+    #[test]
+    fn detects_latin_as_not_rtl() {
+        assert!(!first_strong_is_rtl("Hello"));
+        assert!(!first_strong_is_rtl("DeckCraft"));
+    }
+
+    #[test]
+    fn skips_neutrals_numbers_and_whitespace() {
+        assert!(first_strong_is_rtl("  123 مرحبا"));
+        assert!(first_strong_is_rtl("... (2024) سنة"));
+        assert!(!first_strong_is_rtl("  123 Hello"));
+        assert!(!first_strong_is_rtl(""));
+        assert!(!first_strong_is_rtl("   12345 "));
+    }
+
+    #[test]
+    fn honours_directional_marks() {
+        assert!(first_strong_is_rtl("\u{200F}Hello"));
+        assert!(!first_strong_is_rtl("\u{200E}مرحبا"));
+    }
+}

crates/model/src/lib.rs

@@ -8,6 +8,7 @@
 #![forbid(unsafe_code)]
 
 pub mod anim;
+pub mod bidi;
 pub mod chart;
 pub mod defaults;
 pub mod edit;
@@ -27,6 +28,7 @@ pub use deckcraft_geom::{Rect, Size, Xfrm};
 use serde::{Deserialize, Serialize};
 
 pub use anim::{AnimClass, AnimStart, Animation, Transition};
+pub use bidi::{first_strong_is_rtl, is_rtl_script};
 pub use chart::Chart;
 pub use style::{ColorBase, ColorRef, Effects, Fill, Line, ShapeStyle};
 pub use table::{Cell, Table};
@@ -315,6 +317,10 @@ pub enum ShapeKind {
         xml: String,
         preview: Option<MediaId>,
         label: String,
+        /// The parts its XML points to (SmartArt data, an OLE embedding…), so a save writes them
+        /// back: (relationship id used in `xml`, relationship type, the part as a media item).
+        #[serde(default, skip_serializing_if = "Vec::is_empty")]
+        parts: Vec<(String, String, MediaId)>,
     },
 }
 

crates/pptx/src/opc.rs

@@ -133,7 +133,7 @@ impl Package {
             let (Some(id), Some(ty), Some(target)) = (r.attr("Id"), r.attr("Type"), r.attr("Target")) else { continue };
             let external = r.attr("TargetMode").is_some_and(|m| m.eq_ignore_ascii_case("external"));
             let target = if external { target.to_string() } else { resolve(&base, target) };
-            out.items.push(Rel { id: id.to_string(), kind: ty.rsplit('/').next().unwrap_or(ty).to_string(), target, external });
+            out.items.push(Rel { id: id.to_string(), kind: ty.rsplit('/').next().unwrap_or(ty).to_string(), ty: ty.to_string(), target, external });
         }
         out
     }
@@ -162,6 +162,8 @@ pub struct Rel {
     pub id: String,
     /// Last segment of the relationship type (`slide`, `image`, `media`…).
     pub kind: String,
+    /// The whole relationship type URI, to write it back as it was.
+    pub ty: String,
     /// Absolute part name for internal targets; the URL for external ones.
     pub target: String,
     pub external: bool,

crates/pptx/src/read/chart.rs

@@ -195,9 +195,8 @@ fn chart_within(root: &El, mut budget: usize) -> Option<Chart> {
             "surfaceChart" | "surface3DChart" => ChartType::Surface,
             _ => continue,
         };
-        if let Some(v) = g.child_val("varyColors") {
-            c.vary_colors = v == "1" || v == "true";
-        }
+        // A missing <c:varyColors> means "vary by point" (the schema default is true), as PowerPoint draws it.
+        c.vary_colors = g.child_val("varyColors").is_none_or(|v| v == "1" || v == "true");
         // A bar group without c:gapWidth / c:overlap takes the schema's defaults (150 %, 0 %),
         // not the 219 % / -27 % PowerPoint writes into its new charts.
         let bar_group = g.is("barChart") || g.is("bar3DChart");
@@ -287,6 +286,10 @@ fn chart_within(root: &El, mut budget: usize) -> Option<Chart> {
             c.series.push(ser);
         }
     }
+    // `autoTitleDeleted val="0"` without `c:title`: PowerPoint and LibreOffice draw the series name as the title of a single-series chart.
+    if ch.child("title").is_none() && ch.child("autoTitleDeleted").and_then(|a| a.bool("val")) == Some(false) && c.series.len() == 1 {
+        c.title = c.series.first().map(|s| s.name.clone()).filter(|n| !n.is_empty());
+    }
     let first = *kinds.first()?;
     c.kind = if kinds.iter().any(|k| *k != first) { ChartType::Combo } else { first };
     if c.kind != ChartType::Combo {
@@ -608,4 +611,52 @@ mod tests {
         assert_eq!((t[1].kind, t[1].order), (TrendlineType::Poly, Some(6)));
         assert_eq!((t[2].kind, t[2].period), (TrendlineType::MovingAvg, Some(3)));
     }
+
+    const NS_C: &str = "http://schemas.openxmlformats.org/drawingml/2006/chart";
+    const NS_A: &str = "http://schemas.openxmlformats.org/drawingml/2006/main";
+
+    fn chart(auto_deleted: &str, title: &str, series: usize) -> Chart {
+        let val = r#"<c:val><c:numLit><c:ptCount val="1"/><c:pt idx="0"><c:v>1</c:v></c:pt></c:numLit></c:val>"#;
+        let ser: String = (0..series).map(|i| format!(r#"<c:ser><c:idx val="{i}"/><c:tx><c:v>S{i}</c:v></c:tx>{val}</c:ser>"#)).collect();
+        let plot = format!(r#"<c:plotArea><c:barChart><c:barDir val="col"/>{ser}</c:barChart></c:plotArea>"#);
+        let xml = format!(r#"<c:chartSpace xmlns:c="{NS_C}" xmlns:a="{NS_A}"><c:chart>{title}{auto_deleted}{plot}</c:chart></c:chartSpace>"#);
+        read_chart_xml(xml.as_bytes()).unwrap()
+    }
+
+    #[test]
+    fn single_series_gets_automatic_title() {
+        assert_eq!(chart(r#"<c:autoTitleDeleted val="0"/>"#, "", 1).title.as_deref(), Some("S0"));
+    }
+
+    #[test]
+    fn no_automatic_title_when_deleted_or_multi_series() {
+        assert_eq!(chart(r#"<c:autoTitleDeleted val="1"/>"#, "", 1).title, None);
+        assert_eq!(chart("", "", 1).title, None);
+        assert_eq!(chart(r#"<c:autoTitleDeleted val="0"/>"#, "", 2).title, None);
+    }
+
+    #[test]
+    fn explicit_title_wins() {
+        let t = "<c:title><c:tx><c:rich><a:p><a:r><a:t>Mine</a:t></a:r></a:p></c:rich></c:tx></c:title>";
+        assert_eq!(chart(r#"<c:autoTitleDeleted val="0"/>"#, t, 1).title.as_deref(), Some("Mine"));
+    }
+
+    const NS_CHART: &str = "http://schemas.openxmlformats.org/drawingml/2006/chart";
+
+    fn vary_xml(vary: &str) -> String {
+        let ser = r#"<c:ser><c:idx val="0"/><c:order val="0"/></c:ser>"#;
+        let bar = format!(r#"<c:barChart><c:barDir val="col"/><c:grouping val="clustered"/>{vary}{ser}</c:barChart>"#);
+        format!(r#"<c:chartSpace xmlns:c="{NS_CHART}"><c:chart><c:plotArea>{bar}</c:plotArea></c:chart></c:chartSpace>"#)
+    }
+
+    #[test]
+    fn missing_vary_colors_means_vary_by_point() {
+        assert!(read_chart_xml(vary_xml("").as_bytes()).is_some_and(|c| c.vary_colors));
+    }
+
+    #[test]
+    fn explicit_vary_colors_is_respected() {
+        assert!(read_chart_xml(vary_xml(r#"<c:varyColors val="0"/>"#).as_bytes()).is_some_and(|c| !c.vary_colors));
+        assert!(read_chart_xml(vary_xml(r#"<c:varyColors val="1"/>"#).as_bytes()).is_some_and(|c| c.vary_colors));
+    }
 }

crates/pptx/src/read/mod.rs

@@ -740,19 +740,33 @@ fn sane_len(v: f64, dflt: f64) -> f64 {
 
 /// Does the element (or a descendant) reference a relationship?
 pub fn has_rel_refs(el: &El) -> bool {
-    fn rec(e: &El, depth: usize) -> bool {
+    !rel_refs(el).is_empty()
+}
+
+/// Is this attribute a relationship id (`r:id`, `r:embed`, `r:dm`…)?
+pub fn is_rel_attr(k: &str, v: &str) -> bool {
+    !k.starts_with("xmlns")
+        && k.contains(':')
+        && matches!(k.rsplit(':').next(), Some("id" | "embed" | "link" | "dm" | "lo" | "qs" | "cs" | "pict" | "href"))
+        && !v.is_empty()
+}
+
+/// Every relationship id `el` and its descendants use, sorted and without repeats.
+pub fn rel_refs(el: &El) -> Vec<String> {
+    fn rec(e: &El, out: &mut Vec<String>, depth: usize) {
         if depth > crate::xml::MAX_DEPTH {
-            return false;
+            return;
+        }
+        out.extend(e.attrs.iter().filter(|(k, v)| is_rel_attr(k, v)).map(|(_, v)| v.clone()));
+        for c in e.elements() {
+            rec(c, out, depth + 1);
         }
-        let own = e.attrs.iter().any(|(k, v)| {
-            !k.starts_with("xmlns")
-                && k.contains(':')
-                && matches!(k.rsplit(':').next(), Some("id" | "embed" | "link" | "dm" | "lo" | "qs" | "cs" | "pict" | "href"))
-                && !v.is_empty()
-        });
-        own || e.elements().any(|c| rec(c, depth + 1))
     }
-    rec(el, 0)
+    let mut out = vec![];
+    rec(el, &mut out, 0);
+    out.sort();
+    out.dedup();
+    out
 }
 
 pub fn color_map(cm: &El) -> Vec<(String, String)> {

crates/pptx/src/read/shapes.rs

@@ -449,7 +449,22 @@ fn frame(imp: &mut Imp, part: &Part, ctx: &mut IdCtx, e: &El, depth: usize) -> S
     } else {
         uri.rsplit('/').next().unwrap_or("Object").to_string()
     };
-    s.kind = ShapeKind::Opaque { xml: part.keep(e), preview, label };
+    // Keep the parts it points to so a save writes it back whole (#203). A part with relationships
+    // of its own, or an external link, can't be carried: the save then falls back to the preview.
+    let parts = super::rel_refs(e)
+        .into_iter()
+        .map(|id| {
+            let rel = part.rels.get(&id).filter(|r| !r.external)?;
+            if !imp.pkg.rels(&rel.target).items.is_empty() {
+                return None;
+            }
+            let (kind, target) = (rel.ty.clone(), rel.target.clone());
+            let media = if rel.kind == "diagramData" { diagram_data(imp, &target) } else { imp.media_for(&target) };
+            Some((id, kind, media?))
+        })
+        .collect::<Option<Vec<_>>>()
+        .unwrap_or_default();
+    s.kind = ShapeKind::Opaque { xml: part.keep(e), preview, label, parts };
     s
 }
 
@@ -490,6 +505,34 @@ fn vml_index(pkg: &crate::opc::Package, vml: &str) -> std::collections::HashMap<
     out
 }
 
+/// A diagram's data part, without the link to its cached drawing: that link is a slide
+/// relationship id, which a save renumbers. Only diagrams whose drawing is missing or empty get
+/// here, and those are drawn from their data.
+fn diagram_data(imp: &mut Imp, target: &str) -> Option<deckcraft_model::MediaId> {
+    fn strip(e: &mut El, depth: usize) {
+        if depth > crate::xml::MAX_DEPTH {
+            return;
+        }
+        e.children.retain(|n| !matches!(n, crate::xml::Node::El(c) if c.is("ext") && c.find("dataModelExt").is_some()));
+        for c in e.elements_mut() {
+            strip(c, depth + 1);
+        }
+    }
+    let mut doc = imp.pkg.xml(target)?;
+    strip(&mut doc.root, 0);
+    let xml = format!("<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"yes\"?>\n{}", doc.root.to_xml());
+    let id = deckcraft_model::MediaId(imp.alloc());
+    let content_type = imp.pkg.content_type(target)?;
+    imp.media.push(deckcraft_model::MediaItem {
+        id,
+        name: crate::opc::file_of(target).to_string(),
+        content_type,
+        data: std::sync::Arc::new(xml.into_bytes()),
+        link: None,
+    });
+    Some(id)
+}
+
 /// SmartArt: read the pre-drawn shapes of its drawing part as a group.
 fn smartart(imp: &mut Imp, part: &Part, gd: &El, frame: &Shape, depth: usize) -> Option<Shape> {
     let rel_ids = gd.child("relIds")?;

crates/pptx/src/write/shapes.rs

@@ -437,7 +437,7 @@ pub fn shape(w: &mut W, x: &mut Exp, o: &mut Out, cx: &mut Ctx, s: &Shape, depth
             }
             w.close("p:grpSp");
         }
-        ShapeKind::Opaque { xml, preview, label } => opaque(w, x, o, cx, s, xml, *preview, label),
+        ShapeKind::Opaque { xml, preview, label, parts } => opaque(w, x, o, cx, s, xml, *preview, label, parts),
     }
 }
 
@@ -832,13 +832,32 @@ fn media(w: &mut W, x: &mut Exp, o: &mut Out, id: u32, s: &Shape, m: &deckcraft_
 }
 
 #[allow(clippy::too_many_arguments)]
-fn opaque(w: &mut W, x: &mut Exp, o: &mut Out, cx: &mut Ctx, s: &Shape, xml: &str, preview: Option<deckcraft_model::MediaId>, label: &str) {
-    // Kept XML that references no relationships can be written back as it was.
+fn opaque(
+    w: &mut W,
+    x: &mut Exp,
+    o: &mut Out,
+    cx: &mut Ctx,
+    s: &Shape,
+    xml: &str,
+    preview: Option<deckcraft_model::MediaId>,
+    label: &str,
+    parts: &[(String, String, deckcraft_model::MediaId)],
+) {
+    // Kept XML is written back as it was when every part it references was kept too, with those
+    // parts re-added under this slide's relationship ids.
     if let Ok(doc) = crate::xml::parse(xml.as_bytes())
-        && !crate::read::has_rel_refs(&doc.root)
         && matches!(doc.root.local(), "graphicFrame" | "sp" | "grpSp" | "cxnSp")
+        && let Some(ids) = crate::read::rel_refs(&doc.root)
+            .iter()
+            .map(|r| {
+                let (_, kind, m) = parts.iter().find(|(id, ..)| id == r)?;
+                Some((r.clone(), x.media_rel(o, *m, kind)?))
+            })
+            .collect::<Option<std::collections::HashMap<_, _>>>()
     {
         let mut root = doc.root;
+        set_rel_ids(&mut root, &ids, 0);
+        ole_fallback(&mut root, x, o, preview);
         let id = cx.id_for(s);
         set_cnvpr_id(&mut root, id);
         w.raw(&root.to_xml());
@@ -888,6 +907,52 @@ fn shape_with_id(w: &mut W, x: &mut Exp, o: &mut Out, cx: &mut Ctx, s: &Shape, i
     }
 }
 
+/// A legacy OLE object finds its preview in the slide's VML drawing through `spid`, and PowerPoint
+/// won't open the slide without it. We don't write that drawing, so write PowerPoint's own
+/// fallback form instead: no `spid`, and the preview as a `p:pic`.
+fn ole_fallback(root: &mut crate::xml::El, x: &mut Exp, o: &mut Out, preview: Option<deckcraft_model::MediaId>) {
+    let xfrm = root.child("xfrm").map(|t| {
+        let at = |e: &str, a: &str| t.child(e).and_then(|c| c.attr(a)).unwrap_or("0").to_string();
+        (at("off", "x"), at("off", "y"), at("ext", "cx"), at("ext", "cy"))
+    });
+    let Some(ole) = root
+        .elements_mut()
+        .find(|e| e.is("graphic"))
+        .and_then(|g| g.elements_mut().find(|e| e.is("graphicData")))
+        .and_then(|d| d.elements_mut().find(|e| e.is("oleObj")))
+    else {
+        return;
+    };
+    if ole.child("pic").is_some() || ole.attr("spid").is_none() {
+        return;
+    }
+    ole.attrs.retain(|(k, _)| k != "spid");
+    let rel = preview.and_then(|m| x.media_rel(o, m, "image")).unwrap_or_else(|| x.placeholder_rel(o));
+    let (ox, oy, cx, cy) = xfrm.unwrap_or_default();
+    let pic = format!(
+        r#"<p:pic><p:nvPicPr><p:cNvPr id="0" name=""/><p:cNvPicPr/><p:nvPr/></p:nvPicPr><p:blipFill><a:blip r:embed="{rel}"/><a:stretch><a:fillRect/></a:stretch></p:blipFill><p:spPr><a:xfrm><a:off x="{ox}" y="{oy}"/><a:ext cx="{cx}" cy="{cy}"/></a:xfrm><a:prstGeom prst="rect"><a:avLst/></a:prstGeom></p:spPr></p:pic>"#
+    );
+    if let Ok(d) = crate::xml::parse(pic.as_bytes()) {
+        ole.children.push(crate::xml::Node::El(d.root));
+    }
+}
+
+fn set_rel_ids(e: &mut crate::xml::El, ids: &std::collections::HashMap<String, String>, depth: usize) {
+    if depth > crate::xml::MAX_DEPTH {
+        return;
+    }
+    for (k, v) in &mut e.attrs {
+        if crate::read::is_rel_attr(k, v)
+            && let Some(new) = ids.get(v.as_str())
+        {
+            v.clone_from(new);
+        }
+    }
+    for c in e.elements_mut() {
+        set_rel_ids(c, ids, depth + 1);
+    }
+}
+
 fn set_cnvpr_id(el: &mut crate::xml::El, id: u32) {
     fn rec(e: &mut crate::xml::El, id: u32, depth: usize) -> bool {
         if depth > 8 {

crates/pptx/tests/corpus_media.rs

@@ -63,9 +63,9 @@ fn corpus() -> (Presentation, Vec<u8>, Vec<u8>, Vec<u8>) {
 
     let mut objects = new_slide(&mut p, "Objects");
     let mut diagram = shape(&mut p, "Diagram", 40.0, 80.0, 288.0, 144.0);
-    diagram.kind = ShapeKind::Opaque { xml: SMARTART.into(), preview: None, label: "SmartArt".into() };
+    diagram.kind = ShapeKind::Opaque { xml: SMARTART.into(), preview: None, label: "SmartArt".into(), parts: vec![] };
     let mut embedded = shape(&mut p, "Embedded", 340.0, 80.0, 144.0, 72.0);
-    embedded.kind = ShapeKind::Opaque { xml: OLE.into(), preview: None, label: "DeckCraft.Note.1".into() };
+    embedded.kind = ShapeKind::Opaque { xml: OLE.into(), preview: None, label: "DeckCraft.Note.1".into(), parts: vec![] };
     let mut block_shape = shape(&mut p, "Block", 40.0, 240.0, 120.0, 90.0);
     block_shape.kind = ShapeKind::Model3d { media: block_id, poster: None };
     let mut globe_shape = shape(&mut p, "Globe", 180.0, 240.0, 160.0, 120.0);

crates/pptx/tests/malformed.rs

@@ -251,7 +251,7 @@ fn export_of_odd_models_is_valid() {
     }
     s.shapes.push(Shape {
         id: ShapeId(7),
-        kind: ShapeKind::Opaque { xml: "<not xml".into(), preview: None, label: "Thing".into() },
+        kind: ShapeKind::Opaque { xml: "<not xml".into(), preview: None, label: "Thing".into(), parts: vec![] },
         ..Default::default()
     });
     p.slides.push(Arc::new(s));

crates/pptx/tests/roundtrip.rs

@@ -1681,3 +1681,57 @@ fn radar_stock_and_combo_round_trip() {
         }
     }
 }
+
+/// #203: SmartArt we can't draw kept its XML but lost its diagram parts on save.
+#[test]
+fn smartart_without_a_drawing_keeps_its_parts() {
+    let mut p = defaults::new_presentation(None);
+    let data = p.add_media(
+        "data1.xml",
+        "application/vnd.openxmlformats-officedocument.drawingml.diagramData+xml",
+        br#"<dgm:dataModel xmlns:dgm="http://schemas.openxmlformats.org/drawingml/2006/diagram" xmlns:a="http://schemas.openxmlformats.org/drawingml/2006/main"><dgm:ptLst><dgm:pt modelId="1"><dgm:t><a:p><a:r><a:t>Manager</a:t></a:r></a:p></dgm:t></dgm:pt></dgm:ptLst><dgm:extLst><a:ext uri="http://schemas.microsoft.com/office/drawing/2008/diagram"><dsp:dataModelExt xmlns:dsp="http://schemas.microsoft.com/office/drawing/2008/diagram" relId="rId6"/></a:ext></dgm:extLst></dgm:dataModel>"#.to_vec(),
+    );
+    let mut parts = vec![("rId2".to_string(), "http://schemas.openxmlformats.org/officeDocument/2006/relationships/diagramData".to_string(), data)];
+    for (i, kind) in ["Layout", "QuickStyle", "Colors"].into_iter().enumerate() {
+        let xml = format!(r#"<dgm:{kind} xmlns:dgm="http://schemas.openxmlformats.org/drawingml/2006/diagram"/>"#).into_bytes();
+        let m = p.add_media(&format!("{kind}1.xml"), &format!("application/vnd.openxmlformats-officedocument.drawingml.diagram{kind}+xml"), xml);
+        parts.push((format!("rId{}", i + 3), format!("http://schemas.openxmlformats.org/officeDocument/2006/relationships/diagram{kind}"), m));
+    }
+    let xml = r#"<p:graphicFrame xmlns:p="http://schemas.openxmlformats.org/presentationml/2006/main" xmlns:a="http://schemas.openxmlformats.org/drawingml/2006/main" xmlns:r="http://schemas.openxmlformats.org/officeDocument/2006/relationships"><p:nvGraphicFramePr><p:cNvPr id="4" name="Diagram 3"/><p:cNvGraphicFramePr/><p:nvPr/></p:nvGraphicFramePr><p:xfrm><a:off x="0" y="0"/><a:ext cx="914400" cy="914400"/></p:xfrm><a:graphic><a:graphicData uri="http://schemas.openxmlformats.org/drawingml/2006/diagram"><dgm:relIds xmlns:dgm="http://schemas.openxmlformats.org/drawingml/2006/diagram" r:dm="rId2" r:lo="rId3" r:qs="rId4" r:cs="rId5"/></a:graphicData></a:graphic></p:graphicFrame>"#;
+    let mut s = new_slide(&mut p, "SmartArt");
+    let mut frame = shape(&mut p, "Diagram 3", 0.0, 0.0, 72.0, 72.0);
+    frame.kind = ShapeKind::Opaque { xml: xml.into(), preview: None, label: "SmartArt".into(), parts };
+    s.shapes.push(frame);
+    p.slides.push(Arc::new(s));
+
+    // Twice: the second save starts from what the first one wrote.
+    let q = round(&round(&p));
+    let ShapeKind::Opaque { parts, .. } = &by_name(&q.slides[1], "Diagram 3").kind else { panic!("not kept as an object") };
+    assert_eq!(parts.len(), 4, "data, layout, style and colours all kept");
+    let data = q.media(parts.iter().find(|(_, k, _)| k.ends_with("/diagramData")).expect("data").2).expect("media");
+    let data = String::from_utf8_lossy(&data.data);
+    assert!(data.contains("Manager"), "{data}");
+    assert!(!data.contains("dataModelExt"), "the link to a drawing that isn't written is dropped: {data}");
+}
+
+/// #203: a legacy OLE object (preview in the VML drawing we don't write) is saved in PowerPoint's
+/// fallback form, without `spid` and with a `p:pic` preview, or PowerPoint won't open the file.
+#[test]
+fn legacy_ole_object_is_written_in_the_fallback_form() {
+    let mut p = defaults::new_presentation(None);
+    let bin = p.add_media("oleObject1.bin", "application/vnd.openxmlformats-officedocument.oleObject", b"\xD0\xCF\x11\xE0not-a-real-ole".to_vec());
+    let prev = p.add_media("image1.png", "image/png", png(4, 3, [10, 20, 30]));
+    let xml = r#"<p:graphicFrame xmlns:p="http://schemas.openxmlformats.org/presentationml/2006/main" xmlns:a="http://schemas.openxmlformats.org/drawingml/2006/main" xmlns:r="http://schemas.openxmlformats.org/officeDocument/2006/relationships"><p:nvGraphicFramePr><p:cNvPr id="4" name="Object 3"/><p:cNvGraphicFramePr/><p:nvPr/></p:nvGraphicFramePr><p:xfrm><a:off x="0" y="0"/><a:ext cx="914400" cy="914400"/></p:xfrm><a:graphic><a:graphicData uri="http://schemas.openxmlformats.org/presentationml/2006/ole"><p:oleObj spid="_x0000_s1026" name="Slide" r:id="rId4" progId="PowerPoint.Slide.8"><p:embed/></p:oleObj></a:graphicData></a:graphic></p:graphicFrame>"#;
+    let parts = vec![("rId4".to_string(), "http://schemas.openxmlformats.org/officeDocument/2006/relationships/oleObject".to_string(), bin)];
+    let mut s = new_slide(&mut p, "OLE");
+    let mut frame = shape(&mut p, "Object 3", 0.0, 0.0, 72.0, 72.0);
+    frame.kind = ShapeKind::Opaque { xml: xml.into(), preview: Some(prev), label: "Slide".into(), parts };
+    s.shapes.push(frame);
+    p.slides.push(Arc::new(s));
+
+    let q = round(&round(&p));
+    let ShapeKind::Opaque { xml, parts, preview, .. } = &by_name(&q.slides[1], "Object 3").kind else { panic!("not kept as an object") };
+    assert!(xml.contains("<p:pic>") && !xml.contains("spid"), "{xml}");
+    assert!(preview.is_some(), "the preview picture is kept");
+    assert!(parts.iter().any(|(_, k, _)| k.ends_with("/oleObject")), "the embedding is kept: {parts:?}");
+}

crates/render/src/chart.rs

@@ -44,6 +44,18 @@ fn point_fill(ctx: &Ctx, c: &Chart, i: usize, s: &deckcraft_model::chart::Series
     }
 }
 
+/// Fill of one bar: a `<c:dPt>` fill wins, and a single-series chart that varies colours by point uses one accent per point
+/// (not waterfalls, which are never read from a `<c:barChart>`).
+fn bar_fill(ctx: &Ctx, c: &Chart, si: usize, pi: usize, s: &deckcraft_model::chart::Series) -> Rgba {
+    if s.point_fills.iter().any(|(k, _)| *k == pi) {
+        return point_fill(ctx, c, si, s, pi);
+    }
+    if c.vary_colors && c.series.len() == 1 && s.fill.is_none() && c.kind != ChartType::Waterfall {
+        return series_color(ctx, c, pi);
+    }
+    series_fill(ctx, c, si, Some(s))
+}
+
 fn polyline(pts: &[Point]) -> BezPath {
     let mut p = BezPath::new();
     for (k, q) in pts.iter().enumerate() {
@@ -623,7 +635,7 @@ fn draw_inner(ctx: &mut RenderContext, rctx: &Ctx, c: &Chart, m: Affine, w: f64,
                     };
                     series_color(rctx, c, slot)
                 } else {
-                    point_fill(rctx, c, *si, s, i)
+                    bar_fill(rctx, c, *si, i, s)
                 };
                 ctx.set_transform(m);
                 ctx.set_paint(color(fill, 1.0));

crates/render/src/lib.rs

@@ -309,11 +309,21 @@ pub struct Renderer {
     /// The fill of the group being drawn, with the transform and box it is laid out in: children
     /// filled with the group's fill (`a:grpFill`) show it, as one fill across the whole group.
     group_fill: Option<(Fill, Affine, Rect)>,
+    /// Their aligned outlines, kept from frame to frame.
+    morphs: morph_path::Cache,
 }
 
 impl Default for Renderer {
     fn default() -> Self {
-        Renderer { resources: Resources::new(), paths: Vec::new(), bg: None, drawn: None, view: Affine::IDENTITY, group_fill: None }
+        Renderer {
+            resources: Resources::new(),
+            paths: Vec::new(),
+            bg: None,
+            drawn: None,
+            view: Affine::IDENTITY,
+            group_fill: None,
+            morphs: morph_path::Cache::default(),
+        }
     }
 }
 
@@ -733,6 +743,7 @@ impl Renderer {
             }
         }
         self.paths.clear();
+        self.morphs.sweep();
         self.finish(ctx, w, h)
     }
 
@@ -982,7 +993,7 @@ impl Renderer {
         depth: usize,
     ) {
         let (geo, fades) = match self.paths.iter().find(|p| p.id == s.id) {
-            Some(pm) => morph_path::geometry(pm, s, w, h),
+            Some(pm) => self.morphs.geometry(pm, s, w, h),
             None => (shape_geometry(s, w, h), Vec::new()),
         };
         let fade = |i: usize| fades.get(i).copied().unwrap_or(deckcraft_geom::morph::Fade { fill: 1.0, stroke: 1.0 });
@@ -1410,7 +1421,10 @@ impl Renderer {
             ctx.set_paint(color(c.with_alpha(255), 1.0));
             ctx.set_stroke(kurbo::Stroke::new(g.radius.max(0.0) * 0.95).with_join(kurbo::Join::Round));
             ctx.stroke_path(&silhouette);
-            ctx.fill_path(&silhouette);
+            // A shape without a fill (an outline, a frame) glows along its line only (#225).
+            if fill_alpha.is_some() || content.is_some() {
+                ctx.fill_path(&silhouette);
+            }
             ctx.pop_layer();
         }
         if let Some(rf) = &e.reflection {

crates/render/src/morph_path.rs

@@ -29,12 +29,72 @@ fn ratio(now: f64, own: f64) -> f64 {
     if own.abs() > 1e-9 && r.is_finite() { r } else { 1.0 }
 }
 
-/// The geometry of frame shape `s` at its current size `w` x `h`: both outlines are built at their
-/// own sizes (so the alignment does not change while the box grows), then scaled into the box.
-/// With a [`Fade`] per sub-path.
-pub(crate) fn geometry(pm: &PathMorph, s: &Shape, w: f64, h: f64) -> (Geometry, Vec<Fade>) {
-    let a = shape_geometry(&Shape { geom: pm.from.clone(), ..Shape::default() }, pm.from_box.w, pm.from_box.h);
-    let b = shape_geometry(s, pm.to_box.w, pm.to_box.h);
-    let scale = |x: Xfrm| Vec2::new(ratio(w, x.w), ratio(h, x.h));
-    GeometryMorph::new(&a, &b).at(pm.t, scale(pm.from_box), scale(pm.to_box))
+/// What a [`GeometryMorph`] is built from: both outlines at their own sizes. None of it changes
+/// while a transition plays, only `t` and the current box do.
+#[derive(Debug)]
+struct Source {
+    from: Geom,
+    from_wh: (f64, f64),
+    to: Geom,
+    to_wh: (f64, f64),
+}
+
+impl Source {
+    fn of(pm: &PathMorph, s: &Shape) -> Self {
+        Source { from: pm.from.clone(), from_wh: (pm.from_box.w, pm.from_box.h), to: s.geom.clone(), to_wh: (pm.to_box.w, pm.to_box.h) }
+    }
+
+    fn is(&self, pm: &PathMorph, s: &Shape) -> bool {
+        self.from == pm.from && self.from_wh == (pm.from_box.w, pm.from_box.h) && self.to == s.geom && self.to_wh == (pm.to_box.w, pm.to_box.h)
+    }
+
+    fn build(&self) -> GeometryMorph {
+        let geo = |geom: &Geom, (w, h): (f64, f64)| shape_geometry(&Shape { geom: geom.clone(), ..Shape::default() }, w, h);
+        GeometryMorph::new(&geo(&self.from, self.from_wh), &geo(&self.to, self.to_wh))
+    }
+}
+
+/// The aligned outlines of the morphs being played, kept across frames: aligning is the expensive
+/// part, blending them at `t` is cheap.
+#[derive(Debug, Default)]
+pub(crate) struct Cache {
+    /// With whether the current frame used it.
+    morphs: Vec<(Source, GeometryMorph, bool)>,
+}
+
+impl Cache {
+    /// The geometry of frame shape `s` at its current size `w` x `h`: both outlines are built at
+    /// their own sizes (so the alignment does not change while the box grows), then scaled into the
+    /// box. With a [`Fade`] per sub-path.
+    pub(crate) fn geometry(&mut self, pm: &PathMorph, s: &Shape, w: f64, h: f64) -> (Geometry, Vec<Fade>) {
+        let k = match self.morphs.iter().position(|(src, ..)| src.is(pm, s)) {
+            Some(k) => k,
+            None => {
+                let src = Source::of(pm, s);
+                let m = src.build();
+                self.morphs.push((src, m, false));
+                self.morphs.len() - 1
+            }
+        };
+        let scale = |x: Xfrm| Vec2::new(ratio(w, x.w), ratio(h, x.h));
+        let Some((_, m, used)) = self.morphs.get_mut(k) else {
+            // Not reachable (k was just found or pushed); align afresh rather than panic.
+            return Source::of(pm, s).build().at(pm.t, scale(pm.from_box), scale(pm.to_box));
+        };
+        *used = true;
+        m.at(pm.t, scale(pm.from_box), scale(pm.to_box))
+    }
+
+    /// Ends a frame: forgets the morphs it did not use (their transition is over).
+    pub(crate) fn sweep(&mut self) {
+        self.morphs.retain(|(.., used)| *used);
+        for (.., used) in &mut self.morphs {
+            *used = false;
+        }
+    }
+
+    #[cfg(test)]
+    pub(crate) fn len(&self) -> usize {
+        self.morphs.len()
+    }
 }

crates/render/src/tests.rs

@@ -403,6 +403,34 @@ fn horizontal_bars_list_the_first_category_at_the_bottom_unless_reversed() {
     assert!(draw(true) < 180, "reversed: first category at the top: {}", draw(true));
 }
 
+#[test]
+fn glow_of_an_unfilled_shape_follows_its_line() {
+    // A frame (no fill, thin line) with a strong glow: the glow lines its edge, the inside stays
+    // the slide's white, as PowerPoint draws it.
+    let glow = |fill: Option<Fill>| {
+        let mut sh = Shape {
+            id: ShapeId(610),
+            xfrm: Some(Xfrm::new(100.0, 100.0, 400.0, 300.0)),
+            fill,
+            line: Some(deckcraft_model::style::Line::solid(ColorRef::rgb(deckcraft_color::Rgba::rgb(0, 176, 240)), 0.25)),
+            ..Default::default()
+        };
+        sh.effects = Some(deckcraft_model::Effects {
+            glow: Some(deckcraft_model::style::Glow { color: ColorRef::rgb(deckcraft_color::Rgba::rgb(0, 0, 255)), radius: 8.0 }),
+            ..Default::default()
+        });
+        render_slide(&deck_with(vec![sh]), 0, &RenderOpts { scale: 1.0, ..Default::default() })
+    };
+    let img = glow(Some(Fill::None));
+    let inside = img.pixel(300, 250);
+    assert!(inside[0] > 245 && inside[1] > 245, "{inside:?}");
+    let edge = img.pixel(300, 97);
+    assert!(edge[0] < 230, "{edge:?}");
+    // A filled shape's glow is still the whole silhouette's (the fill covers its inside).
+    let img = glow(Some(Fill::solid(ColorRef::rgb(deckcraft_color::Rgba::rgb(255, 255, 255)))));
+    assert!(img.pixel(300, 94)[0] < 240);
+}
+
 #[test]
 fn placeholder_prompts_only_in_edit_view() {
     let p = Presentation::default();
@@ -715,6 +743,29 @@ fn morph_path_fades_a_fill_only_one_side_has() {
     assert!(half[0] > full[0] + 40 && half[0] < 215, "{half:?} vs {full:?}");
 }
 
+#[test]
+fn morph_path_aligns_once_per_transition() {
+    let (from, to) = (Xfrm::new(0.0, 0.0, 200.0, 200.0), Xfrm::new(0.0, 0.0, 300.0, 150.0));
+    let star = Shape { geom: Geom::preset("star5"), ..Default::default() };
+    let pm = |t: f64| PathMorph { id: ShapeId(10), from: Geom::preset("ellipse"), from_box: from, to_box: to, t };
+    let els = |(g, f): (deckcraft_geom::preset::Geometry, Vec<_>)| (g.paths.iter().map(|p| p.path.elements().to_vec()).collect::<Vec<_>>(), f);
+    let mut cache = morph_path::Cache::default();
+    for t in [0.0, 0.3, 0.7, 1.0] {
+        let got = els(cache.geometry(&pm(t), &star, 250.0, 175.0));
+        // The same as aligning afresh.
+        assert_eq!(got, els(morph_path::Cache::default().geometry(&pm(t), &star, 250.0, 175.0)));
+        cache.sweep();
+    }
+    assert_eq!(cache.len(), 1);
+    // Another target outline is another morph.
+    let _ = cache.geometry(&pm(0.5), &Shape { geom: Geom::preset("rect"), ..Default::default() }, 250.0, 175.0);
+    assert_eq!(cache.len(), 2);
+    // A frame without morphs ends the transition: the cache empties.
+    cache.sweep();
+    cache.sweep();
+    assert_eq!(cache.len(), 0);
+}
+
 #[test]
 fn text_transform_unmirrors_flips() {
     // Asymmetric text rect in a 100×50 box: flips move the rect, never mirror the text.
@@ -1472,7 +1523,7 @@ fn an_object_deckcraft_doesnt_model_shows_its_preview_picture() {
         let sh = Shape {
             id: ShapeId(600),
             xfrm: Some(Xfrm::new(100.0, 100.0, 400.0, 200.0)),
-            kind: ShapeKind::Opaque { xml: String::new(), preview: with_preview.then_some(media), label: "Package".into() },
+            kind: ShapeKind::Opaque { xml: String::new(), preview: with_preview.then_some(media), label: "Package".into(), parts: vec![] },
             ..Default::default()
         };
         std::sync::Arc::make_mut(&mut p.slides[0]).shapes = vec![sh];
@@ -2436,3 +2487,16 @@ fn render_an_emf_file_to_look_at() {
     let img = render_slide(&p, 0, &RenderOpts { scale: 1.0, ..Default::default() });
     let _ = std::fs::write(out, img.to_png());
 }
+
+#[test]
+fn single_series_column_chart_varies_colours_by_point() {
+    let render = |vary: bool| {
+        let mut c = Chart::sample(ChartType::Column);
+        c.series.truncate(1);
+        c.vary_colors = vary;
+        let sh =
+            Shape { id: ShapeId(800), xfrm: Some(Xfrm::new(50.0, 50.0, 400.0, 300.0)), kind: ShapeKind::Chart(Box::new(c)), ..Default::default() };
+        render_slide(&deck_with(vec![sh]), 0, &RenderOpts { scale: 1.0, ..Default::default() }).pixels
+    };
+    assert_ne!(render(true), render(false));
+}

crates/ui-egui/src/canvas.rs

@@ -186,7 +186,10 @@ pub fn show(app: &mut SlideApp, ui: &mut Ui) {
             let idx = d.selection.slide;
             let doc = d.doc.clone();
             let frame = anim.as_ref().map(|(tl, t)| (tl, *t));
-            app.textures.slide(ui.ctx(), &doc, idx, px, visible, true, crate::media::gif_key(&gifs), app.ui.grayscale, &times, frame)
+            // A placeholder's prompt makes way for the caret once it is being typed into.
+            let typing_into = d.selection.text.as_ref().filter(|t| !t.notes && t.cell.is_none()).map(|t| t.shape);
+            let no_prompt = typing_into.filter(|id| d.shape(*id).and_then(|sh| sh.text.as_ref()).is_none_or(|body| body.is_empty()));
+            app.textures.slide(ui.ctx(), &doc, idx, px, visible, true, crate::media::gif_key(&gifs), app.ui.grayscale, &times, no_prompt, frame)
         }
         Some((Target::Master { master }, d)) => master_tex(ui.ctx(), &d.doc, master, None, px, visible),
         Some((Target::Layout { master, layout }, d)) => master_tex(ui.ctx(), &d.doc, master, Some(layout), px, visible),
@@ -906,7 +909,9 @@ fn overlays(app: &mut SlideApp, ui: &Ui, painter: &egui::Painter, xf: Xf, t: &To
             ui.ctx().request_repaint_after(std::time::Duration::from_millis(300));
             // An empty placeholder shows the caret where typing begins too.
             if blink && let Some((top, bot)) = deckcraft_engine::cmd::text::caret_line(st, ts) {
-                painter.line_segment([xf.to_screen(top), xf.to_screen(bot)], Stroke::new(1.5, t.caret));
+                // In the colour of the text being typed: a black caret is lost on a dark slide.
+                let color = deckcraft_engine::cmd::text::caret_color(st, ts).map_or(t.caret, theme::to_color32);
+                painter.line_segment([xf.to_screen(top), xf.to_screen(bot)], Stroke::new(1.5, color));
             }
         }
     }

crates/ui-egui/src/lib.rs

@@ -498,6 +498,8 @@ pub struct SlideApp {
     pub sorter: sorter::State,
     /// The slide thumbnail pane was the last thing clicked, so ⌘A selects slides, not shapes.
     pub(crate) slides_focused: bool,
+    /// A V key press or a Paste event arrived since the last V release (see `keyboard`).
+    v_seen: bool,
     /// Which recent paths exist on disk, probed once per path per session (a dead network share
     /// must not stall every frame). Not persisted.
     recent_checked: HashMap<String, bool>,
@@ -568,6 +570,7 @@ impl SlideApp {
             doc_window: None,
             sorter: sorter::State::default(),
             slides_focused: false,
+            v_seen: false,
             recent_checked: HashMap::new(),
             twisting: false,
             next_file_id: 1,
@@ -758,10 +761,13 @@ impl SlideApp {
         let Some(doc) = self.session.active().map(|d| d.doc.clone()) else { return false };
         let bytes = match format {
             "png" | "jpeg" => {
-                let scale = 2.0;
-                let img = deckcraft_render::render_slide(&doc, slide, &deckcraft_render::RenderOpts { scale, ..Default::default() });
-                let dpi = deckcraft_render::dpi_for_scale(scale);
-                Ok(if format == "png" { img.to_png_at(dpi) } else { img.to_jpeg_at(92, Some(dpi)) })
+                // Every slide for "all slides", one download each, named like the desktop export (#64).
+                let name = self.session.active().map(|d| d.title()).unwrap_or_else(|| "Presentation".into());
+                let mut any = false;
+                for (file, bytes) in web_image_files(&doc, slide, all, &name, ext) {
+                    any = self.download(&file, Ok(bytes)) || any;
+                }
+                return any;
             }
             "pdf" => deckcraft_engine::cmd::file::pdf_bytes(&doc, &extra),
             "gif" => deckcraft_engine::cmd::file::gif_bytes(&doc, &extra),
@@ -1612,10 +1618,25 @@ impl SlideApp {
 
     /// Keyboard and clipboard for the slide (when no text field has focus).
     fn keyboard(&mut self, ctx: &egui::Context) {
+        let events = ctx.input(|i| i.events.clone());
+        // Ctrl+V with only an image on the clipboard: egui-winit sends no Paste event and swallows the
+        // key press, so the release of a V press never seen is the paste. Tracked even while a text
+        // field has focus, so that a V typed there is not taken for one.
+        let mut image_paste = false;
+        for e in &events {
+            match e {
+                egui::Event::Paste(_) | egui::Event::Key { key: egui::Key::V, pressed: true, .. } => self.v_seen = true,
+                egui::Event::Key { key: egui::Key::V, pressed: false, modifiers, .. } => {
+                    // Only a release with Command/Ctrl held is a paste: a bare V release is not.
+                    let seen = std::mem::take(&mut self.v_seen);
+                    image_paste = !seen && (modifiers.command || modifiers.ctrl);
+                }
+                _ => {}
+            }
+        }
         if ctx.memory(|m| m.focused().is_some()) || self.dialog.as_ref().is_some_and(|d| d.modal()) || self.palette.is_some() {
             return;
         }
-        let events = ctx.input(|i| i.events.clone());
         if self.backstage.is_some() {
             // The File tab: its own keys (Esc goes back, arrows walk the side menu) and app
             // shortcuts (New, Open, Command Palette…); typing, pasting or deleting would edit the
@@ -1638,6 +1659,13 @@ impl SlideApp {
             self.drain_requests();
             return;
         }
+        let img = if image_paste { self.services.clipboard_image.as_mut().and_then(|f| f()) } else { None };
+        if let Some(png) = img {
+            let data = deckcraft_engine::cmd::base64_encode(&png);
+            if let Err(e) = self.session.execute("insert.picture", &json!({"name": "Pasted image.png", "data": data})) {
+                self.set_status(e.to_string());
+            }
+        }
         for e in events {
             match e {
                 egui::Event::Text(t) => {
@@ -1674,6 +1702,12 @@ impl SlideApp {
                     }
                 }
                 egui::Event::Key { key, pressed: true, modifiers, .. } => {
+                    if key == egui::Key::Tab {
+                        // The slide has the keyboard, so Tab is ours (indent, tab character, next
+                        // shape). Left to egui it would also focus the first ribbon widget, and
+                        // every key after it would go there instead of the slide (#78).
+                        ctx.memory_mut(|m| m.move_focus(egui::FocusDirection::None));
+                    }
                     if key == egui::Key::Escape && self.anim_preview.is_some() && !modifiers.command && !modifiers.ctrl && !modifiers.alt {
                         self.anim_preview = None;
                         continue;
@@ -1923,6 +1957,25 @@ pub fn now_ms() -> f64 {
     }
 }
 
+/// Images for the browser download: the current slide, or every slide (named `<name>1.png`,
+/// `<name>2.png`... like the native export) when `all`.
+fn web_image_files(doc: &deckcraft_model::Presentation, current: usize, all: bool, name: &str, ext: &str) -> Vec<(String, Vec<u8>)> {
+    let slides: Vec<usize> = if all { (0..doc.slides.len()).collect() } else { vec![current] };
+    let single = slides.len() == 1;
+    let scale = 2.0;
+    let dpi = deckcraft_render::dpi_for_scale(scale);
+    slides
+        .into_iter()
+        .enumerate()
+        .map(|(k, i)| {
+            let img = deckcraft_render::render_slide(doc, i, &deckcraft_render::RenderOpts { scale, ..Default::default() });
+            let bytes = if ext == "png" { img.to_png_at(dpi) } else { img.to_jpeg_at(92, Some(dpi)) };
+            let file = if single { format!("{name}.{ext}") } else { format!("{name}{}.{ext}", k + 1) };
+            (file, bytes)
+        })
+        .collect()
+}
+
 #[cfg(target_arch = "wasm32")]
 fn js_now() -> f64 {
     js_sys::Date::now()
@@ -2007,6 +2060,23 @@ mod tests {
         assert!((shape_rot(harness.state()) - 0.0).abs() < 0.01, "one undo, got {}", shape_rot(harness.state()));
     }
 
+    /// The browser "PNG images (all slides)" export yields one image per slide, not just the selected one (#64).
+    #[test]
+    fn web_export_all_slides_gives_one_file_per_slide() {
+        let mut doc = deckcraft_model::Presentation::default();
+        if let Some(first) = doc.slides.first().cloned() {
+            doc.slides.push(first.clone());
+            doc.slides.push(first);
+        }
+        assert_eq!(doc.slides.len(), 3);
+        let all = web_image_files(&doc, 1, true, "Deck", "png");
+        let names: Vec<&str> = all.iter().map(|(n, _)| n.as_str()).collect();
+        assert_eq!(names, ["Deck1.png", "Deck2.png", "Deck3.png"]);
+        let one = web_image_files(&doc, 1, false, "Deck", "png");
+        assert_eq!(one.len(), 1);
+        assert_eq!(one[0].0, "Deck.png");
+    }
+
     fn title_text(app: &SlideApp) -> String {
         let d = app.session.active().unwrap();
         let sh = &d.doc.slides[0].shapes[0];
@@ -2281,6 +2351,88 @@ mod tests {
         assert_eq!(harness.state().dialog.as_ref().map(|d| d.id.as_str()), Some("export"));
     }
 
+    /// #53: Ctrl+V did nothing for an image-only clipboard: egui-winit sends no Paste event for it and
+    /// swallows the key press, so only the V release reaches the app.
+    #[test]
+    fn ctrl_v_pastes_an_image_when_no_paste_event_arrives() {
+        let session = Session::with_new();
+        let png = {
+            let d = session.active().unwrap();
+            deckcraft_engine::cmd::file::render_png(&d.doc, 0, 0.1, false).0
+        };
+        assert!(!png.is_empty());
+        let services = Services { clipboard_image: Some(Box::new(move || Some(png.clone()))), ..Default::default() };
+        let mut harness = egui_kittest::Harness::builder().with_size(egui::vec2(1200.0, 800.0)).build_ui_state(
+            |ui, app: &mut SlideApp| {
+                app.logic(ui.ctx());
+                app.ui(ui);
+            },
+            SlideApp::new(session, services),
+        );
+        harness.run_steps(2);
+        let pictures = |app: &SlideApp| {
+            let d = app.session.active().unwrap();
+            d.doc.slides[0].shapes.iter().filter(|s| matches!(s.kind, deckcraft_model::ShapeKind::Picture { .. })).count()
+        };
+        let v = |pressed| egui::Event::Key { key: egui::Key::V, physical_key: None, pressed, repeat: false, modifiers: egui::Modifiers::COMMAND };
+        // A text paste (Paste event on the press) does not also paste the image on release.
+        harness.event(egui::Event::Paste("hello".into()));
+        harness.run_steps(2);
+        harness.event(v(false));
+        harness.run_steps(2);
+        assert_eq!(pictures(harness.state()), 0);
+        // A V release without Command/Ctrl is not a paste.
+        harness.event(egui::Event::Key { key: egui::Key::V, physical_key: None, pressed: false, repeat: false, modifiers: egui::Modifiers::NONE });
+        harness.run_steps(2);
+        assert_eq!(pictures(harness.state()), 0);
+        // What egui-winit sends for Ctrl+V with only an image on the clipboard: the release alone.
+        harness.event(v(false));
+        harness.run_steps(2);
+        assert_eq!(pictures(harness.state()), 1);
+    }
+
+    /// #78: after Tab in a text box, typing and deleting no longer reached the text.
+    #[test]
+    fn typing_goes_on_after_tab_in_a_text_box() {
+        let mut harness = egui_kittest::Harness::builder().with_size(egui::vec2(1200.0, 800.0)).build_ui_state(
+            |ui, app: &mut SlideApp| {
+                app.logic(ui.ctx());
+                app.ui(ui);
+            },
+            {
+                let mut session = Session::with_new();
+                session.prefs.autocorrect = false;
+                SlideApp::new(session, Services::default())
+            },
+        );
+        harness.run_steps(2);
+        let title = harness.state().session.active().unwrap().doc.slides[0].shapes[0].id.0;
+        harness.state_mut().session.execute("text.edit", &json!({"id": title})).unwrap();
+        harness.event(egui::Event::Text("ab".into()));
+        harness.run_steps(2);
+        harness.key_press(egui::Key::Tab);
+        harness.run_steps(2);
+        harness.event(egui::Event::Text("c".into()));
+        harness.run_steps(2);
+        assert_eq!(title_text(harness.state()), "ab\tc");
+        harness.key_press(egui::Key::Backspace);
+        harness.run_steps(2);
+        assert_eq!(title_text(harness.state()), "ab\t");
+        assert!(harness.state().session.active().unwrap().selection.text.is_some(), "still editing");
+        // Tab at the start of a paragraph indents it, and typing goes on there too (#93).
+        harness.key_press(egui::Key::Enter);
+        harness.run_steps(2);
+        harness.key_press(egui::Key::Tab);
+        harness.run_steps(2);
+        harness.event(egui::Event::Text("d".into()));
+        harness.run_steps(2);
+        assert_eq!(title_text(harness.state()), "ab\t\nd");
+        let level = |h: &egui_kittest::Harness<SlideApp>| {
+            h.state().session.active().unwrap().doc.slides[0].shapes[0].text.as_ref().unwrap().paragraphs[1].level
+        };
+        assert_eq!(level(&harness), 1);
+    }
+
     #[test]
     fn home_needs_an_open_presentation() {
         let mut app = SlideApp::new(Session::new(), Services::default());

crates/ui-egui/src/textures.rs

@@ -21,6 +21,7 @@ struct Key {
     extra: u64,
     /// The pasteboard region the slide's drawing calls for (canvas only).
     want: Region,
+    skip_text: Option<ShapeId>,
 }
 
 struct Entry {
@@ -247,7 +248,8 @@ impl Textures {
     /// The canvas texture for slide `index`, the slide being `size` pixels, and the region it
     /// covers: the slide, grown over the pasteboard to show what reaches off the slide within
     /// `visible` (the canvas, in pixels from the slide's top-left corner). `extra` changes with the
-    /// GIF frames.
+    /// GIF frames. `skip_text` leaves out one shape's text (the prompt of a placeholder being typed
+    /// into).
     #[allow(clippy::too_many_arguments)]
     pub fn slide(
         &mut self,
@@ -260,6 +262,7 @@ impl Textures {
         extra: u64,
         grayscale: bool,
         gif_times: &[(ShapeId, f64)],
+        skip_text: Option<ShapeId>,
         anim: Option<(&deckcraft_anim::Timeline, f64)>,
     ) -> Option<(TextureHandle, Region)> {
         let slide = p.slides.get(index)?.clone();
@@ -287,6 +290,7 @@ impl Textures {
             edit,
             extra: extra ^ grayscale as u64 ^ anim_key(anim),
             want,
+            skip_text,
         };
         if let Some(e) = &self.canvas
             && e.key == key
@@ -305,6 +309,7 @@ impl Textures {
                 offset: region.offset(),
                 size: Some(region.size()),
                 state,
+                skip_text,
                 ..Default::default()
             };
             deckcraft_render::render_slide_drawn(p, index, &opts)
@@ -362,6 +367,7 @@ impl Textures {
             edit: false,
             extra: 0,
             want: Region::slide(width_px, h),
+            skip_text: None,
         };
         self.clock += 1;
         let clock = self.clock;

docs/animation-parity.md

@@ -43,7 +43,7 @@ perspective-correct subdivided meshes.
 | Duration, advance on click / after time, Apply To All | yes | yes |
 | Transition sounds | yes | yes: Transitions › Sound offers six built-in sounds (synthesised, no sound files shipped), Other Sound…, [Stop Previous Sound] and Loop Until Next Sound; they play in the show and round-trip |
 | Preview in the editor | yes | yes |
-| Morph: objects move, resize, recolour | yes | yes |
+| Morph: objects move, resize, recolour; unmatched text boxes fade in place; a picture's crop morphs | yes | yes (#119, #118) |
 | Morph: Words and Characters | yes | yes (#5) |
 | Morph: geometry (circle to star) | yes | yes (#27) |
 | Morph: `!!` name forcing, pictures, 3-D models, ink | yes | names partly; no 3-D or ink |
@@ -105,4 +105,6 @@ In, Wipe, Zoom, Float In, Grow/Shrink, Pulse, Spin, motion lines): weighted, ~85
 | 2026-10-13 | minor | Animations ▸ Preview and Animation Pane ▸ Play All play the current slide's animations on the editor canvas; preview from the selected effect is still open |
 | 2026-10-13 | major | Transitions measured frame by frame against PowerPoint's video export and retuned (mean diff 35.7 → 15.0); PowerPoint's XML defaults and option meanings; new options |
 | 2026-10-13 | minor | Triggers now play in the slide show (they were read and written but never started), effects of different triggers apply in the order they were clicked |
+| 2026-10-11 | minor | Morph leaves unrelated text boxes unpaired: they fade in place (#119) |
+| 2026-10-11 | minor | Morph animates a changed picture crop (#118) |
 | 2026-10-10 | major | Created: 48/48 transitions, 64 of ~190 animation effects, pane and option depth, estimates |

docs/gaps.md

@@ -225,11 +225,6 @@ Detail in [file-format-parity.md](file-format-parity.md).
 - **Impact:** copy-paste of screenshots is a core workflow.
 - **Estimate:** 2–4 h. **Beta blocker.**
 
-### Tab inside a text box ends text entry (#78)
-- **Evidence:** #78.
-- **Impact:** tab stops and indented lists can't be typed.
-- **Estimate:** 1–2 h.
-
 ### Charts: data grid, elements and the newer chart types
 - **Evidence:** checklist rows "Edit chart data" (P0, partial), "Chart elements" (partial), "Other
   chart types" (partial); `chartex` parts (waterfall, funnel, treemap, sunburst, histogram, Pareto,
@@ -519,6 +514,7 @@ Detail in [localization-parity.md](localization-parity.md).
 | 2026-10-12 | minor | IME composition in slide text and notes, and CJK interface text with real glyphs (#101): the IME gap is now Korean on the web and table-cell underlines |
 | 2026-10-12 | minor | EMF/WMF text, pattern and hatch brushes drawn; legacy OLE and ActiveX previews shown; the SVG gap keeps only EMF clip regions |
 | 2026-10-12 | minor | Text warps render (all 40 presets, adjusts round-trip); the warp gap is now the gallery, command and handles |
+| 2026-10-11 | minor | Removed "Tab inside a text box ends text entry" (#78, fixed) |
 | 2026-10-11 | minor | Animated GIF export landed (#171); the entry now covers video export and animating transitions in the GIF |
 | 2026-10-10 | minor | Noted that no gap blocks alpha (core-workflow gate passes) |
 | 2026-10-10 | major | Created: every gap from the 2026-10-10 re-measure and the 16 open GitHub issues, ranked, with beta blockers marked |

docs/mcp.md

@@ -13,6 +13,58 @@ deck.
 }
 ```
 
+## Confining file access
+
+```sh
+deckcraft-cli mcp --automation-read-root /work/project --automation-write-root /work/project/out
+```
+
+```json
+{"mcpServers": {"deckcraft": {"command": "deckcraft-cli",
+  "args": ["mcp", "--automation-read-root", "/work/project", "--automation-write-root", "/work/project/out"]}}}
+```
+
+The two flags (VectorCraft, PhotoCraft and the other Craft apps take the same ones, so one client
+config works across the suite) keep the agent to the folders you give it:
+
+- Every file a command reads must lie inside the **read root**: `open_presentation` and
+  `file.open`, and `insert_picture`, `insert.picture`, `picture.change`, `insert.audio` and
+  `insert.video` with a `path`. Pictures, audio and video are copied into the deck when they are
+  inserted, so playing them later reads nothing from disk.
+- Every file a command writes must lie inside the **write root**: `save_presentation`, `export`
+  (every format, and every slide of an image export), `file.save`, `file.saveAs`, `file.export`,
+  and `render_slide` with a `path`, plus the `.saving` temporary file a save goes through.
+- Read and write access are separate. Give the same folder twice for both; a root left out grants
+  none of its access (with only `--automation-read-root`, nothing can be written to disk). Without
+  either flag nothing changes.
+- A path is made absolute against the server's working directory, then its links are followed: a
+  file (or folder) link that leads out of a root is outside it. For a file that doesn't exist yet,
+  its nearest existing folder's links are followed and the rest must be plain names, so `..` below a
+  folder that doesn't exist is refused, as is a link that leads nowhere (writing through it would
+  create its target). The result is compared with the root by whole folder names: `/work2/x` is not
+  inside `/work`. On Windows case is ignored, UNC paths (`\\server\share\...`) are resolved like
+  drive-letter ones, and device names (`CON`, `NUL`, `COM1`...) are refused.
+- A refused path is an ordinary tool error the agent can read and correct, for example
+  `automation path rejected: outside the write root /work/project/out: /etc/x.pptx` or
+  `automation filesystem access is not granted: write authority is absent: /work/project/out/x.pptx`.
+- The roots must be existing folders; a missing one stops the server with an error. Each flag is
+  given once (`--flag <dir>` or `--flag=<dir>`).
+
+The flags confine the in-process server, so `--connect` together with them is an error: the server
+would otherwise talk to an app that isn't confined. DeckCraft's desktop app has no equivalent flags
+yet, so a running app (`deckcraft --control`) is not confined. `--sample` is the operator's own
+choice and is opened before the roots apply.
+
+What the roots do not cover: commands that take no path still read and change the open deck, and
+`inspect_document` and `inspect_slide` return it. The system font scan and the app's own recovery
+folder are fixed paths, not agent input, and are not checked. Anything that reads or writes a path
+goes through one place in the engine (`io::read_file` and `io::write_file`); a test keeps the rest of the
+engine from touching the file system on its own.
+
+The checks hold for every thread of the server process. A path is checked, then opened: another
+program that swaps a link in between can still win that race, so the roots keep an agent to the
+files it was given rather than guarding against other software on the computer.
+
 ## Tools
 
 | Tool | What it does |

docs/ui-parity.md

@@ -141,7 +141,7 @@ menu colours taken from the theme tokens (menu `chrome`, page `card`).
 | Edit points on freeforms | yes | **no** |
 | WordArt adjust handles | yellow handles on transformed text | yes, one per adjust when the text has a warp; dragging sets that guide value |
 | Crop handles, crop to shape, aspect ratio | yes | partial |
-| Text caret, selection, double/triple click, drag-select | yes | yes; Tab in text boxes ends editing (#78) |
+| Text caret, selection, double/triple click, drag-select | yes | yes |
 | Exact size/position, lock aspect | yes | yes — Size and Position dialog (height, width, rotation, scale %, lock aspect, position from the top-left), one undo step; ribbon spinners still resize one side at a time |
 | Drag the frame of a text box being edited to move it | yes | yes |
 | Table cells: caret and selection in the cell, click into another cell, drag row and column borders | yes | yes; no cell-range selection by dragging across cells |
@@ -266,4 +266,5 @@ consistency is open (#73, #56).
 | 2026-10-12 | minor | Off-slide objects drawn and editable around the slide in Normal view (#270) |
 | 2026-10-12 | minor | Selection Pane matched to PowerPoint (#133): drag and drop, arrows, groups, eye, Lock |
 | 2026-10-12 | minor | Text editing keys: Ctrl+arrows, Ctrl+Backspace/Delete, Ctrl+Up/Down, Home/End on wrapped lines, Shift+F3, font size keys, as observed in PowerPoint for Windows (#268) |
+| 2026-10-11 | minor | Tab in text boxes keeps editing (#78) |
 | 2026-10-10 | major | Created: shell, panes and dialogs, direct manipulation, shortcuts and visual fidelity against PowerPoint 16.113 |