47 / GESTURE PHYSICS
Pointer Coalescing
The problem
High-frequency pointer hardware produces more samples than pointermove delivers, so ink drawn from the event alone looks sparse and jagged.
The solution
When supported, the path uses every sample from getCoalescedEvents().
This mechanic is best experienced with a pointer.
Experiment
Task: Draw a fast curve across both surfaces and compare path density.
NAIVE
Draw here
THOUGHTFUL
Fallback — getCoalescedEvents unavailable
Draw here
Play with the values
1200ms
3px
How it works
Seen in
Drawing apps
Ink follows the stylus more faithfully when coalesced samples fill gaps between frames.
Signature pads
Fast signatures stay smooth instead of collapsing into sparse polylines.
Gesture recognition
Shape classifiers see denser trajectories without listening at hardware rate.
Whiteboard tools
Freehand strokes remain continuous under rapid pointer motion.