addPointerInputChange

Function

Common
fun VelocityTracker.addPointerInputChange(event: PointerInputChange) =
    addPointerInputChange(event, Offset.Zero)

Track the positions and timestamps inside this event change.

For optimal tracking, this should be called for the DOWN event and all MOVE events, including any touch-slop-captured MOVE event.

Since Compose uses relative positions inside PointerInputChange, this should be taken into consideration when using this method. Right now, we use the first down to initialize an accumulator and use subsequent deltas to simulate an actual movement from relative positions in PointerInputChange. This is required because VelocityTracker requires data that can be fit into a curve, which might not happen with relative positions inside a moving target for instance.

Parameters

eventPointer change to track.
Common
fun VelocityTracker.addPointerInputChange(event: PointerInputChange, offset: Offset)

Track the positions and timestamps inside this event change.

For optimal tracking, this should be called for the DOWN event and all MOVE events, including any touch-slop-captured MOVE event.

Since Compose uses relative positions inside PointerInputChange, this should be taken into consideration when using this method. Right now, we use the first down to initialize an accumulator and use subsequent deltas to simulate an actual movement from relative positions in PointerInputChange. This is required because VelocityTracker requires data that can be fit into a curve, which might not happen with relative positions inside a moving target for instance.

Parameters

eventPointer change to track.
offsetAn optional offset that should be applied to the position of the event before adding it to the tracker.