curve is an object supporting the curve protocol.
begintime and endtime specify the parameter interval of the motion. At begintime the object will be located at the beginning of the curve and at endtime it will be at the end.
loop is a boolean that specifies if the motion is repeated when outside the specified parameter interval.
follow determines if the object will change its orientation to follow the path.
bank determines if the object will roll if the curve makes a turn. bankamplitude specifies how much the object will roll.