Book Image

OpenGL 4 Shading Language Cookbook - Third Edition

By : David Wolff
Book Image

OpenGL 4 Shading Language Cookbook - Third Edition

By: David Wolff

Overview of this book

OpenGL 4 Shading Language Cookbook, Third Edition provides easy-to-follow recipes that first walk you through the theory and background behind each technique, and then proceed to showcase and explain the GLSL and OpenGL code needed to implement them. The book begins by familiarizing you with beginner-level topics such as compiling and linking shader programs, saving and loading shader binaries (including SPIR-V), and using an OpenGL function loader library. We then proceed to cover basic lighting and shading effects. After that, you'll learn to use textures, produce shadows, and use geometry and tessellation shaders. Topics such as particle systems, screen-space ambient occlusion, deferred rendering, depth-based tessellation, and physically based rendering will help you tackle advanced topics. OpenGL 4 Shading Language Cookbook, Third Edition also covers advanced topics such as shadow techniques (including the two of the most common techniques: shadow maps and shadow volumes). You will learn how to use noise in shaders and how to use compute shaders. The book provides examples of modern shading techniques that can be used as a starting point for programmers to expand upon to produce modern, interactive, 3D computer-graphics applications.
Table of Contents (17 chapters)
Title Page
Packt Upsell
Contributors
Preface
Index

Using uniform blocks and uniform buffer objects


If your program involves multiple shader programs that use the same uniform variables, one has to manage the variables separately for each program. Uniform locations are generated when a program is linked, so the locations of the uniforms may change from one program to the next. The data for those uniforms may have to be regenerated and applied to the new locations.

Uniform blocks were designed to ease the sharing of uniform data between programs. With uniform blocks, one can create a buffer object for storing the values of all the uniform variables, and bind the buffer to the uniform block. When changing programs, the same buffer object need only be rebound to the corresponding block in the new program.

A uniform block is simply a group of uniform variables defined within a syntactical structure known as a uniform block. For example, in this recipe, we'll use the following uniform block:

uniform BlobSettings { 
  vec4 InnerColor; 
  vec4 OuterColor...