def tick(self, time):
self.current_time += time
fraction = self.current_time / self.total_time # part of animation done
if fraction > 1:
fraction = 1
current_rotation = Quaternion.new_interpolate(self.start_rotation,
self.dest_rotation,
fraction)
self.object.rotation = current_rotation
return fraction != 1 # continue animation iff it is not completed
