Book Image

OpenGL 4 Shading Language Cookbook - Second Edition

By : David Wolff, David A Wolff
Book Image

OpenGL 4 Shading Language Cookbook - Second Edition

By: David Wolff, David A Wolff

Overview of this book

OpenGL Shading Language (GLSL) is a programming language used for customizing parts of the OpenGL graphics pipeline that were formerly fixed-function, and are executed directly on the GPU. It provides programmers with unprecedented flexibility for implementing effects and optimizations utilizing the power of modern GPUs. With Version 4, the language has been further refined to provide programmers with greater power and flexibility, with new stages such as tessellation and compute. OpenGL 4 Shading Language Cookbook provides easy-to-follow examples that first walk you through the theory and background behind each technique, and then go on to provide and explain the GLSL and OpenGL code needed to implement it. Beginner level through to advanced techniques are presented including topics such as texturing, screen-space techniques, lighting, shading, tessellation shaders, geometry shaders, compute shaders, and shadows. OpenGL Shading Language 4 Cookbook is a practical guide that takes you from the fundamentals of programming with modern GLSL and OpenGL, through to advanced techniques. The recipes build upon each other and take you quickly from novice to advanced level code. You'll see essential lighting and shading techniques; examples that demonstrate how to make use of textures for a wide variety of effects and as part of other techniques; examples of screen-space techniques including HDR rendering, bloom, and blur; shadowing techniques; tessellation, geometry, and compute shaders; how to use noise effectively; and animation with particle systems. OpenGL Shading Language 4 Cookbook 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)
OpenGL 4 Shading Language Cookbook Second Edition
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Introduction


Compute shaders were introduced into OpenGL with Version 4.3. A compute shader is a shader stage that can be used for arbitrary computation. It provides the ability to leverage the GPU and its inherent parallelism for general computing tasks that might have previously been implemented in serial on the CPU. The compute shader is most useful for tasks that are not directly related to rendering, such as physical simulation.

Note

Although APIs such as OpenCL and CUDA are already available for general purpose computation on the GPU, they are completely separate from OpenGL. Compute shaders are integrated directly within OpenGL, and therefore are more suitable for general computing tasks that are more closely related to graphics rendering.

The compute shader is not a traditional shader stage in the same sense as the fragment or vertex shader. It is not executed in response to rendering commands. In fact, when a compute shader is linked with vertex, fragment, or other shader stages, it...