private double findCurvature(InputCursor in) {
if (in.getEventCount() < 3) return 0.0f;
List<AbstractCursorInputEvt> events = in.getEvents();
AbstractCursorInputEvt posEvt = events.get(events.size() - 1);
AbstractCursorInputEvt prev = events.get(events.size() - 2);
AbstractCursorInputEvt prev2 = events.get(events.size() - 3);
if (prev == null) return 0;
if (prev2 == null) return 0;
return findCurvature(
posEvt.getPosX(),
posEvt.getPosY(),
prev.getPosX(),
prev.getPosY(),
prev2.getPosX(),
prev2.getPosY());
}
