Summary

This chapter introduced depth buffers, transformations, GLKit’s matrices, GLKit’s matrix stack, and viewing volumes. None of the examples in this chapter actually change the components of vertices stored in vertex buffers. The vertex positions remain constant. Instead, transformations change the way that the vertices are projected into the 2D pixel color render buffer. Example OpenGLES_Ch5_6 produces some simple animations by dynamically changing the current modelviewMatrix. Chapter 6, “Animation,” further explores the possibilities for animation based on transformations and introduces several other approaches for achieving animation and special effects.