Eraser preview (user request, "加一个淡一点的描边"): new EraserPreviewPainter
shows the eraser circle and a faint red outline over the committed strokes the
eraser currently overlaps, so you can see what is about to be deleted. Mounted
only in eraser mode (tool or barrel/inverted signal) with a live cursor that
follows the hovering/erasing pen; shares _eraserRadius/_pageAspect with the live
erase so preview and action always agree. Kept in its own RepaintBoundary.
Pen-feel fix (the "写字识别成单击" pan-steal): panEnabled now also requires the
last pointer to not be a stylus. Windows fires stylus HOVER before contact, so
_lastStylus is already true when the pen touches down -> the InteractiveViewer's
pan is disabled BEFORE the stroke's first move, instead of one frame late. A
2+ pointer pinch still always pans (focal translation); a finger/mouse down
flips _lastStylus back so finger-pan keeps working.
Grounded in Rnote + Saber research: Saber uses the same button detection we have
(buttons==kSecondaryButton || invertedStylus); the deeper zoom-flash / draw-vs-
pan robustness wants a Saber-style forked InteractiveViewer (single recognizer,
decide-at-start) -- scoped as the next step, not done here. 66/66 tests, linux
build green.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
W1 — Custom pen width + pressure sensitivity (Saber-style):
- Root cause of "压感没用": perfect_freehand 1.0.4 IGNORES real stylus pressure
(hardcodes radius=size/2 when simulatePressure=false) — width never tracked pen
force. Upgraded perfect_freehand ^1.0.0 -> ^2.0.0 (honors real pressure); migrated
all 5 getStroke call sites to the 2.x API (PointVector / StrokeOptions / Offset).
- De-hardcoded `thinning` into `kDefaultPenThinning` (0.85), single source shared by
the on-screen painter and the PDF export path; exposed as PenConfig.pressureSensitivity
with a Pressure Sensitivity slider; live-applies via a config listener.
W3 — Native Windows pen plugin (tilt + barrel/eraser buttons):
- windows/runner/pen_channel.{h,cpp}: observe WM_POINTER at the TOP of MessageHandler
(before HandleTopLevelWindowProc, which Flutter uses to consume pen events), read
GetPointerPenInfo penFlags + tilt, stream over EventChannel('badnote/pen'); non-consuming.
- PenInputService: single latched hardware state (no Win32-pointerId<->event.pointer
correlation); graceful no-op off-Windows.
- pen_canvas maps barrel/inverted/eraser through PenConfig.sideButton/eraserEnd
(eraser/undo/toggleTool/pan) and captures tilt into PenPoint.tilt -> EditorPoint.tilt.
W2 — Zoom flicker: page raster isolated in its own RepaintBoundary (safe interim);
definitive crisp-on-zoom fix gated on the on-device root-cause probe (plan M3).
Plans: ralplan-consensus plan at docs/plans/2026-06-22-badnote-pen-polish.md
(Architect APPROVE-WITH-MUST-FIX M1-M4 + Critic ITERATE->APPROVE).
Tests: 58/58 pass incl. shared-thinning invariant + thinning-affects-outline +
tilt-adapter round-trip. flutter analyze clean; linux debug build OK.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Clean-room reimplementation of Saber's input model: we own the gesture
pipeline so pen draws with real pressure (perfect_freehand), two-finger
pinch zooms/pans, and palm is rejected (stylus-priority, 2nd-pointer
cancels stroke). pdfrx renders one page at a time (PdfPageView, no
gestures) under a shared transform; page-based nav. Material You theme
via dynamic_color (system accent + seed fallback) and a floating tonal
tool palette + page pill. Old pdfrx-overlay spike no longer wired.
