The representation of a 3D world is based on mathematical concepts. If you do not know these concepts, then it will be more difficult to understand certain operations performed in a 3D game. This chapter explains some math concepts that are needed for 3D games. We will learn about the difference between world and relative transforms, and how to use them when working with Components. We will learn about how to use vectors to represent position, direction, velocity, and distance. The concept of traces is explained, and various types of traces are presented. This chapter also shows how to use traces to test collisions in a game.

These are the topics covered in this chapter:

• World and relative transforms
• Points and vectors
• Traces