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

Applying multiple textures

The application of multiple textures to a surface can be used to create a wide variety of effects. The base layer texture might represent the clean surface and the second layer could provide additional detail such as shadow, blemishes, roughness, or damage. In many games, so-called light maps are applied as an additional texture layer to provide information about light exposure, effectively producing shadows, and shading without the need to explicitly calculate the reflection model. These kinds of textures are sometimes referred to as pre-baked lighting. In this recipe, we'll demonstrate this multiple texture technique by applying two layers of texture. The base layer will be a fully opaque brick image, and the second layer will be one that is partially transparent. The non-transparent parts look like moss that has grown on the bricks beneath.

The following image shows an example of multiple textures. The textures on the left are applied to the cube on the right...