OpenGL ES 3.0 Programming Guide, Second Edition

Chapter 5. OpenGL ES Shading Language

As you saw in earlier chapters, shaders are a fundamental concept that lies at the heart of the OpenGL ES 3.0 API. Every OpenGL ES 3.0 program requires both a vertex shader and a fragment shader to render a meaningful picture. Given the centrality of the concept of shaders to the API, we want to make sure you are grounded in the fundamentals of writing shaders before diving into more details of the graphics API.

This chapter’s goal is to make sure you understand the following concepts in the shading language:

• Variables and variable types

• Vector and matrix construction and selection

• Constants

• Structures and arrays

• Operators, control flow, and functions

• Input/output variables, uniforms, uniform ...