Replace the 2-tool ink system with a data-driven, Krita-style
BrushProfile (lib/editor/engine/brush.dart). Adding a brush is a
const map entry, not render-path branching.
Four presets from the rnote/krita spec:
- fountain pen: quadratic (p^2) pressure, wide dynamic width
- ballpoint: near-constant width (thinning 0.15)
- highlighter: flat width, square caps
- pencil: sqrt(p) pressure, moderate width
Pressure is pre-warped per brush via PressureCurve(gamma) before
perfect_freehand; geometry fields (thinning/streamline/smoothing/
caps) flow through the shared stroke recipe so the PDF overlay and
the note/slide PenCanvas both honor the brush. Brush kind is now
persisted on the stroke model. Picker added to all three toolbars.
Opacity/multiply and pencil grain are carried as data but not yet
composited (TODO brush-opacity / brush-texture); this increment is
width + pressure-curve differentiation. analyze clean, 283 tests.
Ties the engine together: a StrokeHost is anything ink attaches to — a PDF page,
an infinite-board region, or a (P5) CAS overlay — with a stable hostId (cache +
persistence key), a contentSize (normalized↔px mapping), and a revision-tracked
StrokeStore. strokesIn(viewport) broad-phase-culls via stroke_bounds for the
board. The viewport mounts one AnnotationLayer per host; nothing in the engine
knows page vs board (the one host-agnostic ink engine).
Makes StrokeStore (P0) + stroke_bounds load-bearing together. Pure; unit-tested.
flutter analyze lib/editor clean; 208/208 tests (+4).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
simplifyStroke reduces a stroke's points via Ramer–Douglas–Peucker at a
normalized perpendicular-distance tolerance: a fast Surface-Pen stroke drops
hundreds of near-collinear samples with no visible change, shrinking the DB row
and speeding re-rasterization (R1/R10). Endpoints + significant vertices kept;
pressure/tilt + color/width/tool/id preserved; <=2 points or tol<=0 are no-ops
(returns the same instance). The commit path can call it before saveHost; the
live in-progress stroke stays untouched.
Pure geometry over EditorStroke; fully unit-tested (collinear collapse, peak
retention, within-tolerance drop, metadata preservation).
flutter analyze lib/editor clean; 198/198 tests (+7).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
strokeBounds (tight AABB over normalized points, null for empty, zero-size for a
single point), strokesBounds (union), and strokeIntersects (does a stroke's box
overlap a viewport rect — touching edges count). Broad-phase primitive for the
infinite board: skip painting/erasing/hit-testing strokes off-screen (R1 perf),
and a cheap pre-filter before the exact per-point eraser test.
Pure geometry over EditorStroke; fully unit-tested.
flutter analyze lib/editor clean; 191/191 tests (+10).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
pdf_service._buildFreehandPdfPath hardcoded its OWN StrokeOptions
(thinning:0.7, streamline:0.5) instead of the shared geometry — the R7
hairline-export divergence. The prior pen-feel commit (streamline 0.5→0.32 on
screen) widened the gap: export still rendered at 0.5.
Extract the ONE perfect_freehand recipe into stroke_geometry.freehandOutlinePoints
(owns thinning/smoothing/streamline/simulatePressure). buildStrokeOutline (screen)
and pdf_service (export, via InkStroke→pfPoints) now both call it, so the
StrokeOptions live in exactly one place and screen↔export can't drift again.
Export now matches screen: thinning 0.85 (kDefaultPenThinning), streamline 0.32.
test/export_geometry_test.dart pins it: buildStrokeOutline traces exactly the
shared outline; default thinning == kDefaultPenThinning; thinning is wired;
empty input is safe.
flutter analyze lib/editor clean; 78/78 tests pass (+4).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Zoom flicker root cause (from the on-device badnote_input_log.txt): the pinch
computed its per-frame scale change as desiredScale / getMaxScaleOnAxis(), i.e.
it fed the LIVE matrix back into its own update. Consecutive frames in the log
show `cur` (the live read) dropping to 0.75-0.89 for a single frame while the
result track stayed smooth, so the code demanded a 1.3-1.4x correction that
popped the zoom bigger/smaller and snapped back. The >1.4 glitch guard missed it
because the spikes sat at 1.31-1.40.
Fix: the scale branch of PenInteractiveViewer now drives the transform
ABSOLUTELY from a gesture-start snapshot (_scaleStart, _referenceFocalPoint) plus
the recognizer's clean, monotonic cumulative details.scale. Each frame is fully
re-derived in closed form (pure scale+translate, no matrix inversion, no live
read-back), so a transient mis-read or interleaved write cannot survive into the
next frame. The per-frame glitch guard now keys on the recognizer's own
scale-ratio (the true finger motion) instead of the corrupted live read. 2-finger
pan still falls out of the same focal-anchor formula.
Pen feel: lower perfect_freehand streamline 0.5 -> 0.32 (new shared constants
kPenStreamline/kPenSmoothing, single-sourced across screen + export so the
parity test still holds). At 0.5 a quick flick lagged so far behind the pen that
short fast strokes collapsed toward their start and rendered as a dot
("写字识别成单击"); 0.32 tracks the real path for a crisper, lower-latency feel.
flutter analyze lib/editor clean; 66/66 tests pass (incl. screen==export parity).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
W4/P0 engine: add engine/stroke_eraser.dart (pure, aspect-corrected) with
whole-stroke `strokeHit` + partial `splitStrokeByCircle`. Grazing a long
stroke now CUTS it into surviving pieces instead of deleting it whole.
Wired through PenCanvas.onEraseStroke (now (index, replacements)) →
pen_editor_screen._eraseStroke (replaceRange); undo/persistence unchanged
(whole-page snapshot). 8 new unit tests; 66/66 pass.
Fix side-button (侧键): _isEraserSignal used `buttons == kSecondaryButton`,
but tip-down + barrel = kStylusContact|kPrimaryStylusButton = 0x03, so the
side button only registered on hover, never while drawing. Now a bitmask
test. (Eraser-end/tilt remain blocked on the silent native badnote/pen
channel — needs on-device native logging.)
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>
