public void setGestureTolerance (float _gestureTolerance) {
		if (_gestureTolerance >= 0f && _gestureTolerance <= 1f) {
			gestureTolerance = _gestureTolerance;
		} else {
			gestureTolerance = 0.5f; // default gesture accuracy
		}
		gestureAngleTolerance = PApplet.radians(40)*gestureTolerance;
	}