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

Diffuse image-based lighting


 Image-based lighting is a technique that involves using an image as a light source.  The image represents an omni-directional view of the environment of the scene. With image-based lighting, the image itself is treated as a highly detailed light source that surrounds the scene completely. Objects in the scene are illuminated by the content of the image, making it possible to have a very complex lighting environment and/or to simulate a real world setting. Often, these images are produced using a special camera or special photographic techniques, and are recorded in high dynamic range. An example of one such image is shown here (image courtesy of USC Institute for Creative Technologies and Paul Debevec): 

These images may be provided as a cube map (set of six images), or some other type of environment map such as a equirectangular panoramic map (the type shown previously). Conversion between the two is straightforward.

Note

Since each texel in the equirectangular...