Merge PR #3788: M5: drag a line's ends (and a polygon's corners) to change its length and angle

ROADMAP.md: union of progress-log lines.
crates/ui-egui/src/i18n/*.tsv (20 catalogs): union of appended keys.

ROADMAP.md

@@ -175,6 +175,7 @@ Ranked; detail and the full milestone table in [docs/roadmap.md](docs/roadmap.md
 - **2026-10-20 (M6, calculation order page):** Prepare a form ▸ Calculation order, a page of its own, lists the calculated fields in the order they calculate with their formulas and values, moved with Up/Down arrows (as Acrobat's Set Field Calculation Order), Alt+↑/↓ or by dragging. A card says what is wrong with the order and holds Fix order; a loop has a card of its own that opens one of its formulas. On the page, each calculated field shows its step, and arrows show what the field in focus reads and what reads it. Estimates unchanged.
 - **2026-10-20 (M6, calculation order):** The order a form's fields calculate in (`/CO`) is read, checked, fixed and set headlessly with `form_calculation_order`: it says which fields read one calculated later (they show stale values), which read each other in a loop, and which the PDF's order leaves out; Fix order moves only what must move, in one undo step, and the form recalculates. Editing a formula no longer moves its field to the end of the order, and a field the order lists twice calculates once. Estimates unchanged.
 - **2026-10-19 (M6, renames keep formulas):** Renaming a field renames it in every calculation that reads it, in the same undo step: `AFSimple_Calculate` field lists, simplified field notation (the comment and the JavaScript after it) and `getField` calls naming it in one string literal; the rest of each script is kept as written. A sum used to drop the renamed field, notation read it as 0 and a script kept a stale value. Field Properties says how many formulas changed and `form_set_props` lists them as `formulas_updated`. Names built at run time and other events' scripts are not rewritten. Estimates unchanged.
+- **2026-10-20 (M5, reshape lines):** A line or arrow could only be moved after it was drawn; its length and angle stayed. A selected line, connected lines, polygon or cloud now has a handle on each end or corner: dragging one reshapes it (Shift holds it to 45°), as one undo step, with the new shape drawn while dragging. `pdfcraft_annot::set_points`, `Edit::ReshapeAnnotation`, `comment_edit points`; comment lists carry the points. Estimates unchanged.
 
 - **2026-10-19 (M14, #3373):** The main menu and its long submenus scroll in short windows, keeping their commands reachable. Estimates unchanged.
 

crates/annot/src/lib.rs

@@ -1788,6 +1788,48 @@ pub fn set_rect(doc: &mut Document, page: usize, index: usize, rect: [f64; 4], m
     apply_text_box(doc, r, rect, meta, false)
 }
 
+/// At most this many points reshape a comment (a drawn polygon has a handful).
+const MAX_POINTS: usize = 100_000;
+
+/// Reshape a line, connected lines, a polygon or a cloud: its points in user space (a line's two
+/// ends, the others' corners), as dragging the comment's handles sets them. `/Rect` follows the
+/// points with room for the line's width and endings, as when the comment was drawn, and the
+/// appearance is redrawn. A measurement keeps the points it measured.
+pub fn set_points(doc: &mut Document, page: usize, index: usize, points: &[[f64; 2]], meta: &Meta) -> Result<(), AnnotError> {
+    let (_, r) = annot_ref(doc, page, index)?;
+    unlocked(doc, r)?;
+    let d = annot_dict(doc, r);
+    if d.contains(b"Measure") {
+        return Err(AnnotError::Invalid("a measurement's points are where it measured".into()));
+    }
+    if points.len() > MAX_POINTS {
+        return Err(AnnotError::Invalid(format!("at most {MAX_POINTS} points")));
+    }
+    let style = Style { width: border_width_of(&d), ..Style::default() };
+    let ends = line_endings_of(&d).unwrap_or_default();
+    let (start, end) = (ends.first().copied().unwrap_or(LineEnding::None), ends.get(1).copied().unwrap_or(LineEnding::None));
+    let subtype = String::from_utf8_lossy(d.name(b"Subtype").unwrap_or_default()).into_owned();
+    let (shape, key): (Shape, &[u8]) = match (subtype.as_str(), points) {
+        ("Line", [from, to]) => (Shape::Line { from: *from, to: *to, start, end }, b"L"),
+        ("Line", _) => return Err(AnnotError::Invalid("a line has two ends".into())),
+        ("PolyLine", _) => (Shape::PolyLine { vertices: points.to_vec(), start, end }, b"Vertices"),
+        ("Polygon", _) => {
+            let cloud = d.get(b"BE").and_then(|b| b.as_dict()).is_some_and(|b| b.name(b"S") == Some(b"C"));
+            (Shape::Polygon { vertices: points.to_vec(), cloud }, b"Vertices")
+        }
+        (other, _) => return Err(AnnotError::Invalid(format!("{other} comments have no points to move"))),
+    };
+    // Checks the points too: finite, and far enough apart to draw.
+    let rect = rect_for(&shape, &style)?;
+    let before = d;
+    doc.update_dict(r, |d| {
+        d.set(key.to_vec(), num_array(&points.concat()));
+        d.set(b"Rect".to_vec(), num_array(&rect));
+        touch(d, meta);
+    })?;
+    redraw_or_restore(doc, r, before)
+}
+
 /// Scale a drawing's strokes into `rect`. The margin between the strokes and the old `/Rect` (half
 /// the line width and a little more) stays the same on each side, so the line isn't clipped.
 fn resize_ink(doc: &mut Document, r: ObjRef, rect: [f64; 4], meta: &Meta) -> Result<(), AnnotError> {
@@ -2096,6 +2138,9 @@ pub struct Summary {
     pub intent: Option<String>,
     /// A Fill & Sign mark ([`is_fill_sign`]).
     pub fill_sign: bool,
+    /// A line's two ends (`/L`), or the corners of connected lines, a polygon or a cloud
+    /// (`/Vertices`), in user space; empty for other comments.
+    pub points: Vec<[f32; 2]>,
 }
 
 fn text_value(doc: &Document, d: &Dict, key: &[u8]) -> Option<String> {
@@ -2150,6 +2195,12 @@ pub fn summaries(doc: &Document) -> Vec<Summary> {
                 }
             }
             let quads = nums(b"QuadPoints").as_chunks::<8>().0.to_vec();
+            // Keep in step with `pdfcraft_render::inspect`.
+            let points = match subtype.as_str() {
+                "Line" => Some(nums(b"L")).filter(|l| l.len() == 4).map(|l| l.as_chunks::<2>().0.to_vec()).unwrap_or_default(),
+                "PolyLine" | "Polygon" => nums(b"Vertices").as_chunks::<2>().0.to_vec(),
+                _ => Vec::new(),
+            };
             let in_reply_to = d.get(b"IRT").map(|o| doc.resolve(o)).and_then(|o| o.as_dict().cloned()).and_then(|p| text_value(doc, &p, b"NM"));
             out.push(Summary {
                 page,
@@ -2169,6 +2220,7 @@ pub fn summaries(doc: &Document) -> Vec<Summary> {
                 locked: annotation_flags(doc, d) & FLAG_LOCKED != 0,
                 intent: d.get(b"IT").and_then(|o| doc.resolve(o).as_name().map(|n| String::from_utf8_lossy(n).into_owned())),
                 fill_sign: is_fill_sign(doc, d),
+                points,
             });
         }
     }

crates/annot/src/tests.rs

@@ -1405,3 +1405,50 @@ fn free_text_properties_show_legacy_or_absent_border_width() {
     .unwrap();
     assert_eq!(props(&doc, 0, index).unwrap().width, Some(4.0));
 }
+
+/// A line's ends and the corners of connected lines and polygons can be moved after drawing:
+/// the points change, `/Rect` follows them (with room for an arrowhead), and the appearance is
+/// drawn anew. A line needs two ends far enough apart; a locked comment keeps its shape.
+#[test]
+fn lines_and_polygons_are_reshaped_by_their_points() {
+    let mut doc = fixture();
+    let l = add_annotation(
+        &mut doc,
+        &new(0, Shape::Line { from: [100.0, 100.0], to: [200.0, 100.0], start: LineEnding::None, end: LineEnding::OpenArrow }),
+        &meta("l"),
+    )
+    .unwrap();
+    let before = ap_content(&doc, &list(&doc, 0)[l]);
+    set_points(&mut doc, 0, l, &[[100.0, 100.0], [100.0, 300.0]], &meta("")).unwrap();
+    let doc2 = reopen(&doc);
+    let d = &list(&doc2, 0)[l];
+    let ends: Vec<f64> = d.get(b"L").unwrap().as_array().unwrap().iter().map(|o| o.as_f64().unwrap()).collect();
+    assert_eq!(ends, [100.0, 100.0, 100.0, 300.0]);
+    let r = rect(d);
+    assert!(r[0] < 100.0 && r[2] > 100.0 && r[1] < 100.0 && r[3] > 300.0, "the rectangle holds the line and its arrowhead: {r:?}");
+    assert!(r[2] - r[0] < 40.0, "and no more: {r:?}");
+    assert_ne!(ap_content(&doc2, d), before, "drawn anew");
+    assert_eq!(summaries(&doc2).into_iter().find(|s| s.index == l).unwrap().points, vec![[100.0, 100.0], [100.0, 300.0]]);
+    // Two ends exactly, far enough apart.
+    assert!(matches!(set_points(&mut doc, 0, l, &[[1.0, 1.0]], &meta("")), Err(AnnotError::Invalid(_))));
+    assert!(matches!(set_points(&mut doc, 0, l, &[[1.0, 1.0], [1.2, 1.0]], &meta("")), Err(AnnotError::Invalid(_))));
+    assert!(matches!(set_points(&mut doc, 0, l, &[[f64::NAN, 1.0], [10.0, 1.0]], &meta("")), Err(AnnotError::Invalid(_))));
+    // A polygon's corner.
+    let g = add_annotation(
+        &mut doc,
+        &new(0, Shape::Polygon { vertices: vec![[300.0, 300.0], [400.0, 300.0], [350.0, 380.0]], cloud: false }),
+        &meta("g"),
+    )
+    .unwrap();
+    set_points(&mut doc, 0, g, &[[300.0, 300.0], [450.0, 300.0], [350.0, 380.0], [300.0, 360.0]], &meta("")).unwrap();
+    let d = &list(&doc, 0)[g];
+    let v: Vec<f64> = d.get(b"Vertices").unwrap().as_array().unwrap().iter().map(|o| o.as_f64().unwrap()).collect();
+    assert_eq!(v.len(), 8);
+    assert!(rect(d)[2] > 450.0);
+    // Locked: refused, and nothing changes.
+    set_locked(&mut doc, 0, l, true).unwrap();
+    assert!(set_points(&mut doc, 0, l, &[[0.0, 0.0], [50.0, 50.0]], &meta("")).is_err());
+    // Other comments have no points to move.
+    let s = add_annotation(&mut doc, &new(0, Shape::Rectangle { rect: [10.0, 10.0, 50.0, 50.0] }), &meta("s")).unwrap();
+    assert!(matches!(set_points(&mut doc, 0, s, &[[0.0, 0.0], [50.0, 50.0]], &meta("")), Err(AnnotError::Invalid(_))));
+}

crates/automation/src/comments.rs

@@ -174,7 +174,7 @@ impl Automation {
         let all = self.comments(a)?;
         let view = |c: &Annotation| -> Value {
             let p = &doc.info.pages[c.page.min(doc.info.pages.len().saturating_sub(1))];
-            json!({
+            let mut v = json!({
                 "id": c.name,
                 "page": c.page + 1,
                 "index": c.index + 1,
@@ -184,7 +184,14 @@ impl Automation {
                 "modified": c.modified,
                 "rect": rect_to_view(p, c.rect),
                 "color": c.color.map(hex),
-            })
+            });
+            // A line's ends, or the corners of connected lines, a polygon or a cloud, as
+            // comment_edit's `points` takes them.
+            if !c.points.is_empty() {
+                let round = |v: f32| (v * 100.0).round() / 100.0;
+                v["points"] = json!(c.points.iter().map(|q| p.user_to_view(q[0], q[1]).map(round)).collect::<Vec<_>>());
+            }
+            v
         };
         let roots: Vec<Value> = all
             .iter()
@@ -632,8 +639,23 @@ impl Automation {
             let (o, d) = (to_user(&info, 0.0, 0.0), to_user(&info, dx, dy));
             edits.push(Edit::MoveAnnotation { page, index, dx: d[0] - o[0], dy: d[1] - o[1] });
         }
+        if let Some(pts) = a.get("points") {
+            let wrong = || ToolError::InvalidArgs("points must be an array of [x, y] points (a line's two ends, or every corner)".into());
+            let points = pts
+                .as_array()
+                .ok_or_else(wrong)?
+                .iter()
+                .map(|p| match p.as_array().map(|p| p.iter().map(|v| v.as_f64()).collect::<Vec<_>>()).as_deref() {
+                    Some([Some(x), Some(y)]) => Ok(to_user(&info, *x, *y)),
+                    _ => Err(wrong()),
+                })
+                .collect::<Result<Vec<_>>>()?;
+            edits.push(Edit::ReshapeAnnotation { page, index, points });
+        }
         if edits.is_empty() {
-            return Err(ToolError::InvalidArgs("nothing to change: pass contents, color, opacity, width, fill, font_size, rect or move".into()));
+            return Err(ToolError::InvalidArgs(
+                "nothing to change: pass contents, color, opacity, width, fill, font_size, rect, move or points".into(),
+            ));
         }
         let edit = if edits.len() == 1 { edits.remove(0) } else { Edit::Batch { label: "Edit comment".into(), edits } };
         self.apply(a, edit)

crates/automation/src/tools.rs

@@ -790,7 +790,7 @@ pub fn tools() -> Vec<ToolDef> {
                 json!({ "doc": doc(), "sort": { "type": "string", "enum": ["page", "author", "date", "type"] }, "out": save_out, "open": open }),
                 &["doc"],
             )),
-        t("comment_edit", "Edit a comment", "Change a comment's text, colour, opacity, line width, font size (text box/typewriter/callout), fill (rectangle/oval/polygon/text box/callout; \"none\" removes it), rectangle (rectangle/oval/text box/stamp) or position (`move` [dx, dy] in points). Stamps keep their original appearance when resized. One undo step.").with(schema(
+        t("comment_edit", "Edit a comment", "Change a comment's text, colour, opacity, line width, font size (text box/typewriter/callout), fill (rectangle/oval/polygon/text box/callout; \"none\" removes it), rectangle (rectangle/oval/text box/stamp), position (`move` [dx, dy] in points) or shape (`points`: a line's two ends, or the corners of connected lines, a polygon or a cloud). Stamps keep their original appearance when resized. One undo step.").with(schema(
             comment_ref(json!({
                 "contents": { "type": "string" },
                 "color": color(),
@@ -800,6 +800,7 @@ pub fn tools() -> Vec<ToolDef> {
                 "font_size": { "type": "number", "minimum": 1, "maximum": 400, "description": "Font size in points of a text box, typewriter text or callout; the box grows to hold the text." },
                 "rect": { "type": "array", "items": { "type": "number" }, "minItems": 4, "maxItems": 4 },
                 "move": point(),
+                "points": { "type": "array", "items": point(), "minItems": 2, "description": "A line's two ends, or every corner of connected lines, a polygon or a cloud, in page coordinates." },
             })),
             &["doc"],
         )),

crates/automation/tests/automation.rs

@@ -6973,3 +6973,21 @@ fn text_box_and_callout_fill_and_border_through_tools() {
         assert_eq!(session.get(saved).unwrap().comment_props(0, index).unwrap().fill, None);
     }
 }
+
+/// `comment_edit points` reshapes a line, connected lines or a polygon, in one undo step, and
+/// `comment_list` reports the points it takes.
+#[test]
+fn comments_are_reshaped_through_the_tool() {
+    let dir = workdir("reshape");
+    let mut a = auto(&dir);
+    let doc = ok(&mut a, "doc_open", json!({ "path": "a.pdf" }))["doc"].as_u64().unwrap();
+    ok(&mut a, "comment_add", json!({ "doc": doc, "page": 1, "type": "line", "from": [20, 40], "to": [120, 40] }));
+    let list = ok(&mut a, "comment_list", json!({ "doc": doc, "page": 1 }));
+    assert_eq!(list["comments"][0]["points"], json!([[20.0, 40.0], [120.0, 40.0]]));
+    ok(&mut a, "comment_edit", json!({ "doc": doc, "page": 1, "index": 1, "points": [[20, 40], [20, 140]] }));
+    let list = ok(&mut a, "comment_list", json!({ "doc": doc, "page": 1 }));
+    assert_eq!(list["comments"][0]["points"], json!([[20.0, 40.0], [20.0, 140.0]]));
+    assert_eq!(ok(&mut a, "edit_undo", json!({ "doc": doc }))["undone"], "Reshape comment");
+    assert!(a.call("comment_edit", &json!({ "doc": doc, "page": 1, "index": 1, "points": [[1, 2]] })).is_err(), "a line has two ends");
+    assert!(matches!(a.call("comment_edit", &json!({ "doc": doc, "page": 1, "index": 1, "points": "no" })), Err(ToolError::InvalidArgs(_))));
+}

crates/engine/src/lib.rs

@@ -263,6 +263,7 @@ fn scope_of(edit: &Edit) -> Scope {
         | Edit::ReplaceText { .. }
         | Edit::EraseInk { .. }
         | Edit::MoveAnnotation { .. }
+        | Edit::ReshapeAnnotation { .. }
         | Edit::ResizeAnnotation { .. }
         | Edit::StyleAnnotation { .. }
         | Edit::FillAnnotation { .. }
@@ -1442,6 +1443,13 @@ pub enum Edit {
         dx: f64,
         dy: f64,
     },
+    /// Reshape a line, connected lines, a polygon or a cloud: its points in user space (a line's
+    /// two ends, the others' corners).
+    ReshapeAnnotation {
+        page: usize,
+        index: usize,
+        points: Vec<[f64; 2]>,
+    },
     /// Resize a rectangle, oval or text box.
     ResizeAnnotation {
         page: usize,
@@ -1887,6 +1895,7 @@ pub const EDIT_LABELS: &[&str] = &[
     "Lock comment",
     "Unlock comment",
     "Move comment",
+    "Reshape comment",
     "Resize comment",
     "Change comment properties",
     "Fill in {name}",
@@ -2012,6 +2021,7 @@ impl Edit {
             Edit::LockAnnotation { locked: true, .. } => Label::of("Lock comment"),
             Edit::LockAnnotation { .. } => Label::of("Unlock comment"),
             Edit::MoveAnnotation { .. } => Label::of("Move comment"),
+            Edit::ReshapeAnnotation { .. } => Label::of("Reshape comment"),
             Edit::ResizeAnnotation { .. } => Label::of("Resize comment"),
             Edit::StyleAnnotation { .. } | Edit::FillAnnotation { .. } | Edit::FontSizeAnnotation { .. } | Edit::SetAnnotationInfo { .. } => {
                 Label::of("Change comment properties")
@@ -2168,6 +2178,7 @@ fn check_permission(edit: &Edit, p: &pdfcraft_cos::Permissions) -> Result<(), Ed
         | Edit::EraseInk { .. }
         | Edit::LockAnnotation { .. }
         | Edit::MoveAnnotation { .. }
+        | Edit::ReshapeAnnotation { .. }
         | Edit::ResizeAnnotation { .. }
         | Edit::StyleAnnotation { .. }
         | Edit::FillAnnotation { .. }
@@ -2434,6 +2445,7 @@ fn run_edit(doc: &mut pdfcraft_cos::Document, edit: &Edit, cx: &mut EditCtx) ->
         }
         Edit::LockAnnotation { page, index, locked } => pdfcraft_annot::set_locked(doc, *page, *index, *locked)?,
         Edit::MoveAnnotation { page, index, dx, dy } => pdfcraft_annot::move_annotation(doc, *page, *index, *dx, *dy, &cx.meta())?,
+        Edit::ReshapeAnnotation { page, index, points } => pdfcraft_annot::set_points(doc, *page, *index, points, &cx.meta())?,
         Edit::ResizeAnnotation { page, index, rect } => pdfcraft_annot::set_rect(doc, *page, *index, *rect, &cx.meta())?,
         Edit::StyleAnnotation { page, index, color, opacity, width, endings } => {
             pdfcraft_annot::set_style(doc, *page, *index, *color, *opacity, *width, endings.as_deref(), &cx.meta())?;
@@ -2771,6 +2783,7 @@ fn comment_list(doc: &pdfcraft_cos::Document) -> Vec<pdfcraft_render::Annotation
             locked: s.locked,
             intent: s.intent,
             fill_sign: s.fill_sign,
+            points: s.points,
         })
         .collect()
 }

crates/render/src/inspect.rs

@@ -386,6 +386,9 @@ pub struct Annotation {
     /// A Fill & Sign mark: typed text, a check, cross, dot or line, or a typed, drawn or picture
     /// signature or initials (the rules of `pdfcraft_annot::is_fill_sign`).
     pub fill_sign: bool,
+    /// The points that shape a line (its two ends, `/L`) or connected lines, a polygon or a
+    /// cloud (their corners, `/Vertices`), in user space; empty for other comments.
+    pub points: Vec<[f32; 2]>,
 }
 
 impl Annotation {
@@ -1149,6 +1152,16 @@ impl<'a> Inspector<'a> {
                 };
                 let in_reply_to = d.get(b"IRT").ok().and_then(|o| self.dict(o)).and_then(|p| self.text(p, b"NM"));
                 let fill_sign = self.is_fill_sign(d, &subtype);
+                // Keep in step with `pdfcraft_annot::summaries`.
+                let key: &[u8] = if subtype == "Line" { b"L" } else { b"Vertices" };
+                let points = match d.get(key).map(|o| self.resolve(o)) {
+                    Ok(Object::Array(v)) if matches!(subtype.as_str(), "Line" | "PolyLine" | "Polygon") => {
+                        let v: Vec<f32> = v.iter().map(|o| o.as_float().unwrap_or(0.0)).collect();
+                        let pts: Vec<[f32; 2]> = v.as_chunks::<2>().0.to_vec();
+                        if subtype == "Line" && pts.len() != 2 { Vec::new() } else { pts }
+                    }
+                    _ => Vec::new(),
+                };
                 info.annotations.push(Annotation {
                     page,
                     subtype,
@@ -1167,6 +1180,7 @@ impl<'a> Inspector<'a> {
                     locked: d.get(b"F").ok().and_then(|f| self.resolve(f).as_i64().ok()).unwrap_or(0) & 128 != 0,
                     intent: self.name(d, b"IT"),
                     fill_sign,
+                    points,
                 });
             }
         }

crates/ui-egui/src/canvas.rs

@@ -5414,6 +5414,7 @@ mod tests {
             locked: false,
             intent: None,
             fill_sign,
+            points: Vec::new(),
         }
     }
 

crates/ui-egui/src/comments.rs

@@ -385,6 +385,9 @@ pub enum Gesture {
     Move { page: usize, index: usize, from: Pos2 },
     /// Resizing a comment by one of its handles: (dx, dy) ∈ {-1, 0, 1}² says which sides move.
     Resize { page: usize, index: usize, handle: (i8, i8), from: Pos2, aspect_ratio: Option<f32> },
+    /// Dragging point `point` of a line, connected lines, a polygon or a cloud (its `points`
+    /// before the drag, in user space) to where the pointer is.
+    Reshape { page: usize, index: usize, point: usize, points: Vec<[f64; 2]> },
 }
 
 #[derive(Clone, Copy, Debug, PartialEq)]
@@ -713,6 +716,42 @@ fn resizable(a: &Annotation) -> bool {
     matches!(a.subtype.as_str(), "Square" | "Circle" | "FreeText" | "Stamp" | "Ink") && a.intent.as_deref() != Some("FreeTextCallout")
 }
 
+/// Lines, connected lines, polygons and clouds: their ends and corners have handles of their own
+/// (measurements keep the points they measured, and a locked comment its shape).
+fn reshapable(a: &Annotation) -> bool {
+    matches!(a.subtype.as_str(), "Line" | "PolyLine" | "Polygon")
+        && !a.points.is_empty()
+        && !a.locked
+        && !a.intent.as_deref().is_some_and(|i| i.ends_with("Dimension"))
+}
+
+/// Whether `tool` picks up a line's end and corner handles: the Select and Fill & Sign tools.
+/// The drawing tools draw from where they are pressed, so a new line starts at the end of the
+/// one just drawn rather than dragging it.
+fn grabs_points(tool: QuickTool) -> bool {
+    !matches!(tool, QuickTool::Comment(t) if t.draws() || t.clicks_points())
+}
+
+/// The point of `a` (an end or a corner) whose handle is at `p` on screen.
+fn point_handle(cx: &PageCx<'_>, a: &Annotation, p: Pos2) -> Option<usize> {
+    a.points.iter().position(|q| cx.to_screen([f64::from(q[0]), f64::from(q[1])]).distance(p) <= 7.0)
+}
+
+/// `points` with point `i` moved to `to`; with Shift, held to the nearest 45° from the point
+/// before it (a line's other end; the first corner turns about the second).
+pub(crate) fn reshaped(points: &[[f64; 2]], i: usize, to: [f64; 2], shift: bool) -> Vec<[f64; 2]> {
+    let mut out = points.to_vec();
+    let anchor = if i == 0 { points.get(1) } else { points.get(i - 1) };
+    let to = match anchor {
+        Some(a) if shift => pdfcraft_engine::measure::snap::constrain(*a, to),
+        _ => to,
+    };
+    if let Some(p) = out.get_mut(i) {
+        *p = to;
+    }
+    out
+}
+
 const HANDLES: [(i8, i8); 8] = [(-1, -1), (0, -1), (1, -1), (1, 0), (1, 1), (0, 1), (-1, 1), (-1, 0)];
 
 fn handle_pos(r: Rect, (hx, hy): (i8, i8)) -> Pos2 {
@@ -1025,7 +1064,7 @@ pub(crate) fn draw_grabs(ui: &egui::Ui, cx: &PageCx<'_>, view: &DocView) -> bool
         return false;
     }
     let cv = &view.comments;
-    if matches!(cv.gesture, Some(Gesture::Resize { page, .. }) if page == cx.page) {
+    if matches!(cv.gesture, Some(Gesture::Resize { page, .. } | Gesture::Reshape { page, .. }) if page == cx.page) {
         return true;
     }
     // A polygon being clicked out keeps its clicks, even near an old shape's handle.
@@ -1041,7 +1080,8 @@ fn grabs(ui: &egui::Ui, cx: &PageCx<'_>, view: &DocView, pick: impl Fn(&Annotati
     if cx.hidden {
         return false;
     }
-    if matches!(view.comments.gesture, Some(Gesture::Move { page, .. } | Gesture::Resize { page, .. }) if page == cx.page) {
+    if matches!(view.comments.gesture, Some(Gesture::Move { page, .. } | Gesture::Resize { page, .. } | Gesture::Reshape { page, .. }) if page == cx.page)
+    {
         return true;
     }
     let Some(p) = press_point(ui, cx) else { return false };
@@ -1057,12 +1097,10 @@ fn press_point(ui: &egui::Ui, cx: &PageCx<'_>) -> Option<Pos2> {
 
 /// Whether `p` is on a resize handle of the selected comment, when it is a resizable `pick`.
 fn on_handle(cx: &PageCx<'_>, view: &DocView, p: Pos2, pick: impl Fn(&Annotation) -> bool) -> bool {
-    view.comments
-        .selected
-        .filter(|(page, _)| *page == cx.page)
-        .and_then(|(_, i)| cx.get(i))
-        .filter(|a| pick(a) && cx.allowed && resizable(a))
-        .is_some_and(|a| HANDLES.into_iter().any(|h| handle_pos(cx.screen_rect(a), h).distance(p) <= 7.0))
+    view.comments.selected.filter(|(page, _)| *page == cx.page).and_then(|(_, i)| cx.get(i)).filter(|a| pick(a) && cx.allowed).is_some_and(|a| {
+        (resizable(a) && HANDLES.into_iter().any(|h| handle_pos(cx.screen_rect(a), h).distance(p) <= 7.0))
+            || (grabs_points(cx.tool) && reshapable(a) && point_handle(cx, a, p).is_some())
+    })
 }
 
 fn clamp_to(r: Rect, p: Pos2) -> Pos2 {
@@ -1087,9 +1125,14 @@ fn select_input(
         let r = cx.screen_rect(a);
         HANDLES.into_iter().find(|h| handle_pos(r, *h).distance(p) <= 7.0)
     };
+    // Ends and corners of a selected line, connected lines, polygon or cloud.
+    let point_at =
+        |p: Pos2| -> Option<usize> { selected.filter(|a| cx.allowed && grabs_points(cx.tool) && reshapable(a)).and_then(|a| point_handle(cx, a, p)) };
     let mut consumed = false;
     if let Some(p) = pointer {
-        if let Some(h) = handle_at(p) {
+        if point_at(p).is_some() {
+            ui.ctx().set_cursor_icon(egui::CursorIcon::Crosshair);
+        } else if let Some(h) = handle_at(p) {
             ui.ctx().set_cursor_icon(match h {
                 (0, _) => egui::CursorIcon::ResizeVertical,
                 (_, 0) => egui::CursorIcon::ResizeHorizontal,
@@ -1105,7 +1148,11 @@ fn select_input(
         && pressed_here
         && let Some(o) = origin
     {
-        if let (Some(h), Some(a)) = (handle_at(o), selected) {
+        if let (Some(point), Some(a)) = (point_at(o), selected) {
+            let points = a.points.iter().map(|q| [f64::from(q[0]), f64::from(q[1])]).collect();
+            cv.gesture = Some(Gesture::Reshape { page: cx.page, index: a.index, point, points });
+            consumed = true;
+        } else if let (Some(h), Some(a)) = (handle_at(o), selected) {
             // On screen, the image is also turned by the view's rotation.
             let turned = !cx.xf.rot.is_multiple_of(180);
             let aspect_ratio = view.signature_drag.aspect_ratio(cx.page, a.index).map(|ratio| if turned { ratio.recip() } else { ratio });
@@ -1127,7 +1174,7 @@ fn select_input(
             consumed = true;
         }
     }
-    if matches!(cv.gesture, Some(Gesture::Move { page, .. } | Gesture::Resize { page, .. }) if page == cx.page) {
+    if matches!(cv.gesture, Some(Gesture::Move { page, .. } | Gesture::Resize { page, .. } | Gesture::Reshape { page, .. }) if page == cx.page) {
         consumed = true;
     }
     if resp.drag_stopped()
@@ -1154,6 +1201,14 @@ fn select_input(
                     }
                 }
             }
+            Some(Gesture::Reshape { page, index, point, points }) if page == cx.page => {
+                cv.gesture = None;
+                let shift = ui.input(|i| i.modifiers.shift);
+                let moved = points.get(point).is_some_and(|q| cx.to_screen(*q).distance(p) >= 2.0);
+                if moved {
+                    view.pending_edit = Some(Edit::ReshapeAnnotation { page, index, points: reshaped(&points, point, cx.to_user(p), shift) });
+                }
+            }
             _ => {}
         }
     }
@@ -1264,6 +1319,9 @@ pub(crate) fn paint_page(ui: &egui::Ui, painter: &egui::Painter, cx: &PageCx<'_>
             return paint_gesture(painter, cx, view);
         }
         let shift = ui.input(|i| i.modifiers.shift);
+        if cx.allowed && grabs_points(cx.tool) && reshapable(a) {
+            return paint_points(painter, cx, view, a, pointer, shift);
+        }
         let r = cx.adjusted_rect(a, cv.gesture.as_ref(), pointer, shift, view.pending_edit.as_ref()).expand(2.0);
         painter.rect_stroke(r, CornerRadius::ZERO, Stroke::new(1.0, SELECT_BLUE), egui::StrokeKind::Middle);
         if cx.allowed && resizable(a) {
@@ -1276,6 +1334,56 @@ pub(crate) fn paint_page(ui: &egui::Ui, painter: &egui::Painter, cx: &PageCx<'_>
     paint_gesture(painter, cx, view);
 }
 
+/// A selected line, connected lines, polygon or cloud: a handle on each end or corner and, while
+/// one is dragged (or its edit is on its way), the new shape over the old.
+/// The points a selected line, polygon or cloud is drawn with while it changes: an end or corner
+/// being dragged, the whole comment being moved by its body, or the edit just released (until the
+/// page is drawn again). `None` while it isn't changing.
+fn changing_points(
+    gesture: Option<&Gesture>,
+    pending: Option<&Edit>,
+    (page, index): (usize, usize),
+    points: &[[f64; 2]],
+    to_user: impl Fn(Pos2) -> [f64; 2],
+    pointer: Option<Pos2>,
+    shift: bool,
+) -> Option<Vec<[f64; 2]>> {
+    let shifted = |dx: f64, dy: f64| points.iter().map(|q| [q[0] + dx, q[1] + dy]).collect();
+    match (gesture, pending) {
+        (Some(Gesture::Reshape { page: p, index: i, point, points: from }), _) if (*p, *i) == (page, index) => {
+            pointer.map(|at| reshaped(from, *point, to_user(at), shift))
+        }
+        (Some(Gesture::Move { page: p, index: i, from }), _) if (*p, *i) == (page, index) => pointer.map(|at| {
+            let (a, b) = (to_user(*from), to_user(at));
+            shifted(b[0] - a[0], b[1] - a[1])
+        }),
+        (_, Some(Edit::ReshapeAnnotation { page: p, index: i, points: to })) if (*p, *i) == (page, index) => Some(to.clone()),
+        (_, Some(Edit::MoveAnnotation { page: p, index: i, dx, dy })) if (*p, *i) == (page, index) => Some(shifted(*dx, *dy)),
+        _ => None,
+    }
+}
+
+fn paint_points(painter: &egui::Painter, cx: &PageCx<'_>, view: &DocView, a: &Annotation, pointer: Option<Pos2>, shift: bool) {
+    let cv = &view.comments;
+    let points: Vec<[f64; 2]> = a.points.iter().map(|q| [f64::from(q[0]), f64::from(q[1])]).collect();
+    let changing = changing_points(cv.gesture.as_ref(), view.pending_edit.as_ref(), (cx.page, a.index), &points, |p| cx.to_user(p), pointer, shift);
+    let changed = changing.is_some();
+    let points = changing.unwrap_or(points);
+    let screen: Vec<Pos2> = points.iter().map(|q| cx.to_screen(*q)).collect();
+    if changed {
+        let stroke = Stroke::new(1.5, SELECT_BLUE);
+        painter.add(if a.subtype == "Polygon" {
+            egui::Shape::closed_line(screen.clone(), stroke)
+        } else {
+            egui::Shape::line(screen.clone(), stroke)
+        });
+    }
+    for c in screen {
+        painter.circle(c, 4.5, Color32::WHITE, Stroke::new(1.0, SELECT_BLUE));
+    }
+    paint_gesture(painter, cx, view);
+}
+
 fn paint_gesture(painter: &egui::Painter, cx: &PageCx<'_>, view: &DocView) {
     let now = painter.ctx().input(|i| i.time);
     for s in view.comments.settling.iter().filter(|s| s.page == cx.page && now - s.since < SETTLE_SECS) {
@@ -1984,6 +2092,24 @@ pub fn status_badge(state: &str) -> Option<(&'static str, &'static str, Color32)
 #[cfg(test)]
 mod tests {
     use super::*;
+
+    /// A selected line is drawn where it is going: moved by its body (both ends follow the
+    /// pointer), with an end dragged (that end alone), and as released until the page is drawn.
+    #[test]
+    fn a_moved_or_reshaped_line_is_drawn_at_its_new_points() {
+        let line = [[10.0, 10.0], [50.0, 10.0]];
+        let to_user = |p: Pos2| [f64::from(p.x), f64::from(p.y)];
+        let moving = Gesture::Move { page: 0, index: 3, from: pos2(20.0, 10.0) };
+        let at = Some(pos2(25.0, 30.0));
+        assert_eq!(changing_points(Some(&moving), None, (0, 3), &line, to_user, at, false), Some(vec![[15.0, 30.0], [55.0, 30.0]]));
+        assert_eq!(changing_points(Some(&moving), None, (0, 4), &line, to_user, at, false), None, "another comment's move");
+        let released = Edit::MoveAnnotation { page: 0, index: 3, dx: 5.0, dy: 20.0 };
+        assert_eq!(changing_points(None, Some(&released), (0, 3), &line, to_user, None, false), Some(vec![[15.0, 30.0], [55.0, 30.0]]));
+        let dragging = Gesture::Reshape { page: 0, index: 3, point: 1, points: line.to_vec() };
+        let to = Some(pos2(60.0, 10.0));
+        assert_eq!(changing_points(Some(&dragging), None, (0, 3), &line, to_user, to, false), Some(vec![[10.0, 10.0], [60.0, 10.0]]));
+        assert_eq!(changing_points(None, None, (0, 3), &line, to_user, to, false), None, "not changing");
+    }
     use pdfcraft_render::TextGlyph;
 
     /// One glyph per character, `w` points wide, on a line of `em`-point text whose baseline is at `y`, drawn

crates/ui-egui/src/editing.rs

@@ -972,6 +972,7 @@ fn comment_page(edit: &Edit) -> Option<usize> {
         | Edit::ReplyToAnnotation { page, .. }
         | Edit::SetAnnotationStatus { page, .. }
         | Edit::MoveAnnotation { page, .. }
+        | Edit::ReshapeAnnotation { page, .. }
         | Edit::ResizeAnnotation { page, .. }
         | Edit::StyleAnnotation { page, .. }
         | Edit::FillAnnotation { page, .. }

crates/ui-egui/src/i18n/ar.tsv

@@ -2757,3 +2757,5 @@ certificate	Version	الإصدار
 	Paragraph spacing	تباعد الفقرات
 	Less	أقل
 	Other options	خيارات أخرى
+# Lines, connected lines and polygons reshaped by their ends and corners (M5).
+	Reshape comment	إعادة تشكيل التعليق

crates/ui-egui/src/i18n/bg.tsv

@@ -2444,3 +2444,5 @@ animation effects	Off	Изключени
 	Paragraph spacing	Разстояние между абзаците
 	Less	По-малко
 	Other options	Други опции
+# Lines, connected lines and polygons reshaped by their ends and corners (M5).
+	Reshape comment	Промяна на формата на коментара

crates/ui-egui/src/i18n/cs.tsv

@@ -2555,3 +2555,5 @@ animation effects	Off	Vypnuto
 	Paragraph spacing	Mezera mezi odstavci
 	Less	Méně
 	Other options	Další možnosti
+# Lines, connected lines and polygons reshaped by their ends and corners (M5).
+	Reshape comment	Změnit tvar komentáře

crates/ui-egui/src/i18n/de.tsv

@@ -2482,3 +2482,5 @@ animation effects	Off	Aus
 	Paragraph spacing	Absatzabstand
 	Less	Weniger
 	Other options	Weitere Optionen
+# Lines, connected lines and polygons reshaped by their ends and corners (M5).
+	Reshape comment	Kommentar umformen

crates/ui-egui/src/i18n/el.tsv

@@ -2487,3 +2487,5 @@ animation effects	Off	Ανενεργά
 	Paragraph spacing	Απόσταση παραγράφων
 	Less	Λιγότερα
 	Other options	Άλλες επιλογές
+# Lines, connected lines and polygons reshaped by their ends and corners (M5).
+	Reshape comment	Αλλαγή σχήματος σχολίου

crates/ui-egui/src/i18n/es.tsv

@@ -2621,3 +2621,5 @@ animation effects	Off	Desactivados
 # Historical snapshot notice bar (View signed version / View revision).
 	You are viewing the signed version of “{from}” (revision {rev}). It is a snapshot: changes here won't affect the original.	Estás viendo la versión firmada de «{from}» (revisión {rev}). Es una instantánea: los cambios aquí no afectarán al original.
 	You are viewing revision {rev} of “{from}”. It is a snapshot: changes here won't affect the original.	Estás viendo la revisión {rev} de «{from}». Es una instantánea: los cambios aquí no afectarán al original.
+# Lines, connected lines and polygons reshaped by their ends and corners (M5).
+	Reshape comment	Cambiar la forma del comentario

crates/ui-egui/src/i18n/fr.tsv

@@ -2481,3 +2481,5 @@ animation effects	Off	Désactivés
 	Paragraph spacing	Espacement des paragraphes
 	Less	Moins
 	Other options	Autres options
+# Lines, connected lines and polygons reshaped by their ends and corners (M5).
+	Reshape comment	Modifier la forme du commentaire

crates/ui-egui/src/i18n/hu.tsv

@@ -2480,3 +2480,5 @@ animation effects	Off	Ki
 	Paragraph spacing	Bekezdéstávolság
 	Less	Kevesebb
 	Other options	Egyéb beállítások
+# Lines, connected lines and polygons reshaped by their ends and corners (M5).
+	Reshape comment	Megjegyzés alakjának módosítása

crates/ui-egui/src/i18n/it.tsv

@@ -2693,3 +2693,5 @@ certificate	SHA-256 digest	Impronta SHA-256
 	Paragraph spacing	Spaziatura paragrafi
 	Less	Meno
 	Other options	Altre opzioni
+# Lines, connected lines and polygons reshaped by their ends and corners (M5).
+	Reshape comment	Modifica la forma del commento

crates/ui-egui/src/i18n/ja.tsv

@@ -2481,3 +2481,5 @@ animation effects	Off	オフ
 	Paragraph spacing	段落間隔
 	Less	折りたたむ
 	Other options	その他のオプション
+# Lines, connected lines and polygons reshaped by their ends and corners (M5).
+	Reshape comment	コメントの形状を変更

crates/ui-egui/src/i18n/kk.tsv

@@ -2479,3 +2479,5 @@ animation effects	Off	Өшірулі
 	Paragraph spacing	Абзац аралығы
 	Less	Азырақ
 	Other options	Басқа параметрлер
+# Lines, connected lines and polygons reshaped by their ends and corners (M5).
+	Reshape comment	Пікір пішінін өзгерту

crates/ui-egui/src/i18n/lt.tsv

@@ -2731,3 +2731,5 @@ theme	Appearance	Išvaizda
 	Paragraph spacing	Tarpas tarp pastraipų
 	Less	Mažiau
 	Other options	Kitos parinktys
+# Lines, connected lines and polygons reshaped by their ends and corners (M5).
+	Reshape comment	Keisti komentaro formą

crates/ui-egui/src/i18n/pl.tsv

@@ -2457,3 +2457,5 @@ animation effects	Off	Wyłączone
 	Paragraph spacing	Odstęp między akapitami
 	Less	Mniej
 	Other options	Inne opcje
+# Lines, connected lines and polygons reshaped by their ends and corners (M5).
+	Reshape comment	Zmień kształt komentarza

crates/ui-egui/src/i18n/pt-br.tsv

@@ -2495,3 +2495,5 @@ animation effects	Off	Desativados
 	Paragraph spacing	Espaçamento entre parágrafos
 	Less	Menos
 	Other options	Outras opções
+# Lines, connected lines and polygons reshaped by their ends and corners (M5).
+	Reshape comment	Alterar a forma do comentário

crates/ui-egui/src/i18n/ru.tsv

@@ -2394,3 +2394,5 @@ animation effects	Off	Выкл
 	Paragraph spacing	Интервал между абзацами
 	Less	Меньше
 	Other options	Другие параметры
+# Lines, connected lines and polygons reshaped by their ends and corners (M5).
+	Reshape comment	Изменить форму комментария

crates/ui-egui/src/i18n/sl.tsv

@@ -2486,3 +2486,5 @@ animation effects	Off	Izklopljeni
 	Paragraph spacing	Razmik med odstavki
 	Less	Manj
 	Other options	Druge možnosti
+# Lines, connected lines and polygons reshaped by their ends and corners (M5).
+	Reshape comment	Spremeni obliko komentarja

crates/ui-egui/src/i18n/te.tsv

@@ -2390,3 +2390,5 @@ animation effects	Off	ఆఫ్
 	Paragraph spacing	పేరా అంతరం
 	Less	తక్కువ
 	Other options	ఇతర ఎంపికలు
+# Lines, connected lines and polygons reshaped by their ends and corners (M5).
+	Reshape comment	వ్యాఖ్య ఆకారాన్ని మార్చు

crates/ui-egui/src/i18n/tr.tsv

@@ -2477,3 +2477,5 @@ animation effects	Off	Kapalı
 	Paragraph spacing	Paragraf aralığı
 	Less	Daha az
 	Other options	Diğer seçenekler
+# Lines, connected lines and polygons reshaped by their ends and corners (M5).
+	Reshape comment	Yorumun şeklini değiştir

crates/ui-egui/src/i18n/uk.tsv

@@ -2503,3 +2503,5 @@ animation effects	Off	Вимкнено
 	Paragraph spacing	Інтервал між абзацами
 	Less	Менше
 	Other options	Інші параметри
+# Lines, connected lines and polygons reshaped by their ends and corners (M5).
+	Reshape comment	Змінити форму коментаря

crates/ui-egui/src/i18n/vi.tsv

@@ -2733,3 +2733,5 @@ key	Space	Space
 # Historical snapshot notice bar (View signed version / View revision).
 	You are viewing the signed version of “{from}” (revision {rev}). It is a snapshot: changes here won't affect the original.	Bạn đang xem phiên bản đã ký của “{from}” (bản sửa đổi {rev}). Đây là ảnh nhanh: các thay đổi ở đây không được áp dụng đến bản gốc.
 	You are viewing revision {rev} of “{from}”. It is a snapshot: changes here won't affect the original.	Bạn đang xem bản sửa đổi {rev} của “{from}”. Đây là ảnh nhanh: các thay đổi ở đây không được áp dụng đến bản gốc.
+# Lines, connected lines and polygons reshaped by their ends and corners (M5).
+	Reshape comment	Đổi hình dạng nhận xét

crates/ui-egui/src/i18n/zh-hans.tsv

@@ -2445,3 +2445,5 @@ animation effects	Off	关
 	Paragraph spacing	段落间距
 	Less	收起
 	Other options	其他选项
+# Lines, connected lines and polygons reshaped by their ends and corners (M5).
+	Reshape comment	更改注释形状

crates/ui-egui/src/i18n/zh-hant.tsv

@@ -2431,3 +2431,5 @@ animation effects	Off	關
 	Paragraph spacing	段落間距
 	Less	收起
 	Other options	其他選項
+# Lines, connected lines and polygons reshaped by their ends and corners (M5).
+	Reshape comment	變更註解形狀

crates/ui-egui/tests/comments.rs

@@ -645,6 +645,58 @@ fn comments_are_selected_moved_and_deleted_with_the_select_tool() {
     assert_eq!(comments(&h).len(), 1);
 }
 
+/// A line's ends have handles: dragging one with the Select tool changes the line's length and
+/// angle (Shift holds it to 45°), as one undo step. The line tool keeps drawing from an end: a
+/// new line starts there rather than dragging the one just drawn.
+#[test]
+fn line_ends_are_dragged_to_change_length_and_angle() {
+    let mut h = harness(|app| app.set_option("quick", "line").unwrap());
+    drag_pt(&mut h, (40.0, 100.0), (140.0, 100.0));
+    let line = comments(&h).into_iter().find(|a| a.subtype == "Line").expect("a line");
+    assert_eq!(line.points.len(), 2);
+    let ends = |h: &Harness<'static, PdfCraftApp>| comments(h).into_iter().find(|a| a.index == line.index).unwrap().points;
+    // With the line tool, a drag from the end just drawn draws another line.
+    let first = ends(&h);
+    drag_pt(&mut h, (first[1][0], first[1][1]), (140.0, 40.0));
+    assert_eq!(comments(&h).iter().filter(|a| a.subtype == "Line").count(), 2, "a second line");
+    assert_eq!(ends(&h), first, "the first one stays");
+    h.state_mut().set_option("quick", "select").unwrap();
+    click_pt(&mut h, (90.0, 100.0));
+    assert_eq!(h.state().views[0].comments.selected, Some((0, line.index)));
+    // Drag the right end up and further right: longer, and turned.
+    let [_, end] = [line.points[0], line.points[1]];
+    drag_pt(&mut h, (end[0], end[1]), (200.0, 160.0));
+    let p = ends(&h);
+    assert!((p[0][0] - 40.0).abs() < 1.0 && (p[0][1] - 100.0).abs() < 1.0, "the other end stays: {p:?}");
+    assert!((p[1][0] - 200.0).abs() < 1.0 && (p[1][1] - 160.0).abs() < 1.0, "the dragged end follows: {p:?}");
+    let id = h.state().views[0].id;
+    assert_eq!(h.state().session.get(id).unwrap().can_undo(), Some("Reshape comment"));
+    // Shift: held to the nearest 45° from the other end (39° here).
+    let a = at(&h, 200.0, 160.0);
+    let b = at(&h, 150.0, 190.0);
+    h.hover_at(a);
+    h.run_steps(1);
+    h.event(egui::Event::ModifiersChanged(egui::Modifiers::SHIFT));
+    h.drag_at(a);
+    h.run_steps(1);
+    for k in 1..=4 {
+        h.hover_at(a + (b - a) * (k as f32 / 4.0));
+        h.run_steps(1);
+    }
+    h.drop_at(b);
+    h.run_steps(3);
+    h.event(egui::Event::ModifiersChanged(egui::Modifiers::NONE));
+    h.run_steps(1);
+    let p = ends(&h);
+    let (dx, dy) = (p[1][0] - p[0][0], p[1][1] - p[0][1]);
+    assert!(dx > 50.0 && (dx - dy).abs() < 0.5, "45°: {p:?}");
+    // Undo puts the line back as it was before the drag.
+    h.state_mut().undo();
+    h.run_steps(2);
+    let p = ends(&h);
+    assert!((p[1][0] - 200.0).abs() < 1.0 && (p[1][1] - 160.0).abs() < 1.0, "{p:?}");
+}
+
 #[test]
 fn a_shape_just_drawn_resizes_from_its_handles_without_the_select_tool() {
     // #2338: the new shape showed its handles, but only the Select tool answered them.

parity/acrobat-features.toml

@@ -3959,6 +3959,18 @@ tools = ["comment_delete"]
 evidence = ["crates/ui-egui/tests/comments.rs::comments_are_selected_moved_and_deleted_with_the_select_tool", "crates/annot/src/tests.rs::delete_takes_popup_and_reply_chain"]
 notes = "deletes the pop-up and the reply thread"
 
+[[feature]]
+id = "comment.reshape"
+title = "Change a line's ends and a polygon's corners after drawing"
+area = "E"
+tier = "P1"
+milestone = "M5"
+status = "shipped"
+commands = []
+tools = ["comment_edit"]
+evidence = ["crates/annot/src/tests.rs::lines_and_polygons_are_reshaped_by_their_points", "crates/ui-egui/tests/comments.rs::line_ends_are_dragged_to_change_length_and_angle", "crates/automation/tests/automation.rs::comments_are_reshaped_through_the_tool"]
+notes = "A selected line, arrow, connected lines, polygon or cloud has a handle on each end or corner (instead of the frame); dragging one changes the length and angle (Shift holds it to 45° from the point before), with the new shape drawn while dragging, as one undo step (Edit::ReshapeAnnotation). The drawing tools keep drawing from an end (a new line starts there); the Select tool reshapes. /Rect follows the points with room for the width and arrowheads, and the appearance is drawn anew. Headless: comment_edit `points`; comment_list reports them. Measurements keep the points they measured; locked comments keep their shape. Not yet: adding or removing a corner."
+
 [[feature]]
 id = "comment.edit-comment-text"
 title = "Edit comment text"