Rotate View: a two-finger rotation on a Mac trackpad turns the view about the pointer

A two-finger rotation on a Mac trackpad did not turn the view. With
the new General preference Trackpad Gesture to Rotate View
(`trackpadRotateView`, on by default) and the pointer over the canvas,
the rotation turns the view about the pointer, keeping the document
point under it in place. The view does not turn until the rotation
reaches 5°; it then turns by the whole rotation and follows each later
rotation event. A rotation ends 0.25 s after its last event. A rotation
in the same frame as a pinch zooms and turns about the same point.

egui reports the gesture as `Event::Rotate`: egui-winit makes it from
winit's macOS rotation gesture, and eframe makes it from Safari's
gesture events in the web build. Rotation events that arrive while
fingers are on a touch screen do not turn the view. With the
preference off, the gesture does not turn the view.

Docs: docs/mcp.md, docs/target-app-parity.md, docs/hardware-parity.md.

docs/hardware-parity.md

@@ -22,7 +22,7 @@ on huge documents. Pen input is pressure-only and Windows-first.
 | Pen pressure | yes (Wacom, Windows Ink, macOS tablet events) | **no** (winit reports none, #852) | yes (pointer force via `WM_POINTER`) | X11 only via XWayland (Preferences › Performance › Linux Display Server, #1151); none on Wayland (#491, #764) | browser pointer events, with coalesced events; Apple Pencil on iPad (hover, palm rejection: fingers navigate after a pen contact until reload) | partial: 4–8 h for macOS and Wayland (winit 0.31) |
 | Pen tilt, bearing, barrel rotation (6D Art Pen) | yes, drives brushes | no | no | no | no | missing: 4–8 h after the input layer (#372) |
 | Pen eraser end | yes | no | no | no | no | missing |
-| Touch gestures (pinch zoom, two-finger pan, rotate view, Touch workspace) | yes (Windows touch, Surface) | trackpad pinch and scroll | pinch, pan; two-finger tap undo, three-finger redo (#585) | same where winit reports touch | eframe until the first pen contact, then Pointer Events (pen and fingers told apart); long press opens the context menu | partial: touch workspace and rotate gesture missing, 3–5 h |
+| Touch gestures (pinch zoom, two-finger pan, rotate view, Touch workspace) | yes (Windows touch, Surface) | trackpad pinch, scroll and rotate | pinch, pan; two-finger tap undo, three-finger redo (#585) | same where winit reports touch | eframe until the first pen contact, then Pointer Events (pen and fingers told apart); long press opens the context menu | partial: touch workspace and touch-screen rotation missing, 3–5 h |
 | Trackpad (smooth scroll, pinch) | yes | yes | precision touchpads | yes | yes | done |
 | HiDPI / Retina, per-monitor scale | yes | yes | yes | yes | yes | done; a window dragged between monitors of different scale can still grow on Windows (#1459, open); the custom title bar's window on Windows stays truly borderless so the pointer lines up with what is drawn (#1791, #1758; awaiting the reporter's confirmation) |
 | Multiple monitors: panels and document windows on another screen | yes | no (one OS window) | no | no | — | missing: 6–10 h (with multiple windows, gap G7) |

docs/mcp.md

@@ -2123,7 +2123,9 @@ The Selection & Anchor Display and General preferences apply to `pointer_gesture
 
 The preferences for the view need the desktop app (`vectorcraft-cli mcp --connect`): `zoomWithMouseWheel` (the
 wheel zooms about the pointer, Shift-wheel scrolls up and down, Cmd/Ctrl-wheel sideways; the control channel's
-`ui.wheel` turns the wheel), `zoomToSelection` (on: Zoom In and Zoom Out centre the selection), `showToolTips`,
+`ui.wheel` turns the wheel), `trackpadRotateView` (on by default: a two-finger rotation on a Mac trackpad, in the
+macOS app or in Safari, turns the view about the pointer once it reaches 5°; with it off, the gesture does not turn
+the view), `zoomToSelection` (on: Zoom In and Zoom Out centre the selection), `showToolTips`,
 `anchorSize` (1–7), `gridColor`, `gridStyle`, `gridsInBack`, `guideColor`, `guideStyle`, `showPixelGrid` (on by
 default: in View › Pixel Preview at 600% zoom and above, a line at every document pixel over the art),
 `recentFontsCount`, `antiAliasedArtwork` (on by default; off, the canvas draws the art with hard edges — a pixel is

docs/target-app-parity.md

@@ -561,6 +561,7 @@ Moved from the ROADMAP's "Shipped so far" on 2026-10-10. Update it when a featur
   View › Rotate View turns the view to the status bar's preset angles (`view.rotate {angle}`, which takes any angle). View › Rotate View to Selection turns the view to the angle of the selected objects' bounding box, so the box is square to the window (`view.rotateToSelection`).
   When the view angle changes (a Rotate View drag, the status bar's angle menu, Reset Rotate View or a saved view) and the desktop app renders the frame at the new angle on the render worker, the canvas draws the last frame turned to the new angle until that frame is ready. It used to draw no art until then.
   With the view rotated, a second Escape less than a second after the first resets the rotation, as Reset Rotate View does. The first Escape may end something else, such as isolation mode or a path being drawn. The second resets the view only when it has nothing else to end, and an Escape that closes a menu does not count. After a click, or a press of another key that is not a modifier (Shift, Control, Alt/Option or Command), the next Escape counts as the first. With the Rotate View tool chosen, one Escape resets the view.
+  A two-finger rotation on a Mac trackpad turns the view about the pointer once it reaches 5° (Preferences › General › Trackpad Gesture to Rotate View, on by default).
   The status bar navigator's field shows the active artboard's number and name, and its drop-down lists every artboard by number and name, as the Artboards panel does. Choosing an artboard in the list makes it the active artboard and fits it in the window (`view.goToArtboard`). The list opens on the active artboard's row and lays out only the rows in view and at most one more.
 - **Geometry and effects:**
   - **Open-path anchor Delete:** Delete/Backspace removes selected anchors and their adjoining segments, leaving drawable runs as separate open subpaths of the original object. Surviving curves and appearance stay intact; one Undo restores the document and selection, and a second Delete removes the selected remainder. Explicit Remove Anchor Points still reconnects/refits. Four core regressions, one full-frame Delete/Backspace regression and three existing removal/segment controls pass, covering these distinctions, multiple deletions, transformed geometry and mixed whole-object selection. Behaviour references: the legacy public [Illustrator reference guide, Add or delete an anchor point](https://helpx.adobe.com/content/dam/help/en/pdf/illustrator_reference.pdf) distinguishes keyboard deletion from dedicated removal; the current [Add or remove anchor points](https://helpx.adobe.com/illustrator/desktop/draw-shapes-and-paths/modify-paths/add-or-remove-anchor-points.html) describes the dedicated tools. Other G11 gaps and scores/hours remain unchanged.