I put this together some time ago;
It enables you to determine the point of impact and from that you could determine whether the impact occured on the left or right hand side of the paddle.
Then, based on the length of the paddle, halved, you could then proportion this value to be used to calculate a new vector for the ricochet. So, if it right on the far right end of the paddle, this would be your shallowest angle back out etc.