Lucky for me I enjoyed math in school, so I never asked this question. Up to this point, Unity3D has handled all the reflective forces on a rigid body so I haven’t had to do any calculations like that…THANK GOODNESS. I might like math, but I’m not quite that crazy…yet. During development of Shape Sprout, I realized that I needed to shoot a “shape bullet” from the tip of her wand out to where the player touched the screen. “Oh, that’s easy…I’ll just use Lerp() or MoveTowards()!”, I thought excitedly. That works great…until the shape bullet stopped at the spot the player touched the screen and didn’t continue on like I wanted it to. *FACEPALM* Ya, I really should have known that was going to happen, lack of sleep maybe? Now how do I figure that one out? Hmm…I seem to remember something about slope and y = mx+b in algebra. No, that was slope intercept form…I need just the slope. Thank goodness for Google, there isn’t anyway I can keep all this stuff in my head. So, its y2 – y1/x2 – x1. Easy enough, we know start x and y position (wand tip) and we know end x and y position (where the player touched the screen), we can get slope! Okay great, that works now and the “shape bullet” is following the path like we want it to! Now…how can I make Kari’s arm rotate in line of where the shape bullet is going? Trigonometry to the rescue! I already extensively use COS in the movement of Jumble’s hot air balloon, I know there is something that would help. Google to the rescue again! ARCTAN…yup, looks like we just feed it the slope and it gives us back what we need. Or so I thought. Something isn’t quite right, her arm is rotating but it is moving at a different speed than what it should really be rotating. That is when I discovered the value you get from ARCTAN is in radians and not degrees *FACEPALM*, why didn’t I know that? Luckily we have a constant we can use called Mathf.Rad2Deg so I don’t have to figure it out. Now just offset the angle slightly since our arm sprite is at about a 45 degree angle and voilà, it works as intended! Only and Indie Dev would get excited about something like this. I’m pretty sure there is probably an easier way Unity lets you do all this and I just don’t know it yet. But, don’t say you will never use Algebra or Trigonometry.