Chapter 10: Coordinate Rotation and Bouncing Off Angles

Overview

What well cover in this chapter:

• Simple coordinate rotation

• Advanced coordinate rotation

• Bouncing off an angle

• Important formulas in this chapter

This chapter covers a particular technique known as coordinate rotation . As its name implies, this technique involves rotating a coordinate around a point. While useful all by itself, coordinate rotation is indispensable for several very interesting effects. One of those is the answer to a question that has continuously been asked on all the Flash boards for years : How do I bounce something off an angled surface? Ill cover how to do that in this chapter.

Another useful application of coordinate rotation is for calculating the reactions of two objects that bounce off each other. Ill show you how to do that in the next chapter, where I discuss the conservation of momentum. However, in that chapter, Im going to assume you know about coordinate rotation already. So, if youre thinking of jumping ahead to that chapter, I recommend you sit tight and get through this one first.