Preferences › Devices › Enable Touch Gestures (on by default) was stored
but nothing read it: no touch gesture was implemented.
- `touch::Taps` follows the fingers egui reports (winit reads them from
the system: WM_POINTER on Windows): fingers down together and lifted
within half a second, none moved more than 16 points, is a tap. Two
fingers undo, three redo, with the preference on.
- egui makes the first finger the pointer too, so it has pressed on the
canvas by the time a second lands: that press is dropped then (its tool
interaction rolled back), and the rest of the gesture presses nothing.
The tap so undoes what came before it, not the first finger's mark.
- A pen is one contact, so pen strokes and taps are unaffected; pinch zoom
is unchanged.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
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