private KeyFrame interpolateRotation(KeyFrame start, KeyFrame end, double timestamp) {
double startAngle = start.getOrientation();
double endAngle = end.getOrientation();
double theta = Angle.getRotationAngle(startAngle, endAngle);
if (end.useRelativeAngle()) {
theta = endAngle - startAngle;
}
double ds = start.getTimestamp();
double duration = end.getTimestamp() - ds;
double d = (timestamp - ds) / duration;
double angle = startAngle + d * theta;
Point2D p = start.getPosition();
KeyFrame frame =
new KeyFrame(
TrajectoryMovement.ROTATION,
0,
angle,
0,
start.getRotationSpeed(),
p,
timestamp,
start.getSourceLine());
return frame;
}
