void addPosition(Duration timeStamp, Point position)

Add a given position corresponding to a specific time.

If kAssumePointerMoveStoppedTime has elapsed since the last call, then earlier data will be discarded.

Source 

void addPosition(Duration timeStamp, Point position) {
  if (timeStamp - _lastTimeStamp >= kAssumePointerMoveStoppedTime)
    _strategy.clear();
  _lastTimeStamp = timeStamp;
  _strategy.addMovement(timeStamp, position);
}