protected void GetRotatedDrawLocation(float interp, out float x, out float y, out float angle)
{
angle = GetDrawAngle(interp);
float abs_x = GetDrawLocationX(interp);
float abs_y = GetDrawLocationY(interp);
// Need to rotate points
PointF vec = new PointF(abs_x, abs_y);
vec = vec.Rotate(-angle);
x = vec.X;
y = vec.Y;
}