Pointer Events report a press of a pen's eraser end as the eraser button
(button 5). The browser build ignored that press. It now presses like the
tip, and the web runner writes the pen's samples into a stylus feed with
the end they came from, so the canvas selects the Eraser tool before the
press and the press erases. The next press of the tip selects the tool
used before, as on Linux and macOS. A hovering pen keeps the end it last
pressed with, since Pointer Events report no end while a pen hovers. A
mouse or finger takes the pen out of the feed; a palm rejected while the
pen presses does not.
Docs: docs/hardware-parity.md, docs/gaps.md (G14),
docs/target-app-parity.md.
A pen reports far more often than frames come (an Apple Pencil up to 240 times
a second): the canvas now hands the tool each move of the frame with its
pressure instead of the last one only, and the web shell feeds Safari's
coalesced pen events. Mouse input is unchanged.
Read pen and finger Pointer Events in the web shell (capture phase) instead of
eframe's touch handlers, which can't tell a pen from a finger and see every
touch twice. The pen drives the pointer with its pressure and hovers; fingers
are touch contacts for pinch, two-finger pan and undo/redo taps. Once a pen
has been seen (remembered in localStorage), a finger or a resting palm never
presses a tool on the canvas, and a pen landing cancels fingers already down.
A long press drops the tool press and opens the context menu.
The page no longer scrolls, zooms or selects under touch, and the canvas
stays inside the safe areas of a full-screen app.
dotCooCoo