Unbuffer MotionEvent objects for touch events to avoid ignoring points and reduce latency
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and reduce latency It fixes the problem that, when the touchscreen/stylus sampling rate is higher than the screen refresh rate, multiple points from the touchscreen/stylus are batched into a single MotionEvent object with extra latency, and all points of this object except the most current one are ignored. For reference: - https://developer.android.com/develop/ui/views/touch-and-input/stylus-input/advanced-stylus-features#rendering - https://developer.android.com/reference/android/view/MotionEvent#batching
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It fixes the problem that, when the touchscreen/stylus sampling rate is higher than the screen refresh rate, multiple points from the touchscreen/stylus are batched into a single
MotionEventobject with extra latency, and all points of this object except the most current one are ignored.For reference:
In the following samples, strokes were drawn with stylus (whose sampling rate is 240Hz), and the FPS is 60Hz. Red points and blue strokes were presented by the "show taps" option in developer options, and the green strokes were presented by xournal++ (
xournalpppackage in termux x11 repo). Before the patch was applied, 3 of every 4 points were ignored by termux-x11.