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 ScrollEnd or a short event gap.
Platform-provided Qt.ScrollMomentum events 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 animated angleDelta mouse-wheel behavior remains intact.
The integration test sends phased QWheelEvent pixel deltas and verifies scaled movement, continued movement after release, and the platform-momentum handoff.
Activity
12
TNL4021mo agoTested this PR on an Omarchy laptop using only a trackpad. The momentum after finger release feels substantially better, but active finger-down scrolling remains close to 0.5.0 and noticeably slower than KDE Discover.
Discover is a useful comparison because it is also a Qt Quick application running through the same Wayland/libinput session with the same trackpad and scrolls normally on the affected machine.
Kirigami has an established Wayland/libinput workaround that prefers angleDelta when both are present because pixelDelta is too slow: https://invent.kde.org/frameworks/kirigami/-/merge_requests/415
I opened a focused follow-up against this branch that retains its bounded momentum and uses Kirigami’s standard 60px-per-notch conversion during the active gesture: https://github.com/kevinherron/omawrite/pull/1
All 13 tests pass, and the combined behavior was validated on the affected hardware.
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.