Improve touchpad scrolling with kinetic momentum - #42
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Scale pixel-precise movement and preserve gesture velocity after release. Use platform momentum when available and bound the fallback coast.
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Sample size of 1 when it comes to testing this change on a physical touchpad. Works great on my old ThinkPad X1 Carbon Gen 6. I'll test on my XPS 14 when it gets here next week. |
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Pixel-precise touchpad scrolling currently applies raw deltas directly, so movement feels slow and stops abruptly when the fingers lift. This change scales touchpad movement by 2× and estimates gesture velocity to provide bounded, decaying momentum after
ScrollEndor a short event gap.Platform-provided
Qt.ScrollMomentumevents take precedence over the fallback momentum to prevent double scrolling. New gestures, mouse-wheel input, other movement, and content bounds stop momentum cleanly. The existing animatedangleDeltamouse-wheel behavior remains intact.The integration test sends phased
QWheelEventpixel deltas and verifies scaled movement, continued movement after release, and the platform-momentum handoff.