Pro OpenGL ES for iOS

Chapter 10

OpenGL ES 2, Shaders, and…

Her angel's face, As the great eye of heaven shined bright, And made a sunshine in the shady place.

—Edmund Spenser

There are two different versions of the OpenGL ES graphics library on your iOS devices. This book has largely dealt with the higher-level one, known as OpenGL ES 1, sometimes referred to as 1.1 or 1.x. The second version is a rather confusingly named OpenGL ES 2. The first one is by far the easier of the two; it comes with all sorts of helper libraries doing much of the 3D mathematics and all of the lighting, coloring, and shading on your behalf. ES 2 eschews all of those niceties and is sometimes referred to as the “programmable function” version (vs. ES 1's “fixed function” design, which ...