Book Image

OpenGL 4.0 Shading Language Cookbook

Book Image

OpenGL 4.0 Shading Language Cookbook

Overview of this book

The 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 4.0, the language has been further refined to provide programmers with greater flexibility, and additional features have been added such as an entirely new stage called the tessellation shader. The OpenGL Shading Language 4.0 Cookbook provides easy-to-follow examples that first walk you through the theory and background behind each technique then go on to provide and explain the GLSL and OpenGL code needed to implement it. Beginning level through to advanced techniques are presented including topics such as texturing, screen-space techniques, lighting, shading, tessellation shaders, geometry shaders, and shadows. The OpenGL Shading Language 4.0 Cookbook is a practical guide that takes you from the basics of programming with GLSL 4.0 and OpenGL 4.0, through basic lighting and shading techniques, to more advanced techniques and effects. It presents techniques for producing basic lighting and shading effects; 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, shadowing, tessellation and geometry shaders, noise, and animation. The OpenGL Shading Language 4.0 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 (16 chapters)
OpenGL 4.0 Shading Language Cookbook
About the Author
About the Reviewers

Creating a night-vision effect

Noise can be useful to simulate static or other kinds of electronic interference. This recipe is a fun example of that. We'll create the look of night-vision goggles with some noise thrown in to simulate some random static in the signal. Just for fun, we'll also outline the scene in the classic "binocular" view. The following image shows an example:

We'll apply the night-vision effect as a second pass to the rendered scene. The first pass will render the scene to a texture (see Chapter 4, Rendering to a Texture), and the second pass will apply the night-vision effect.

Getting ready

Create an FBO for the first pass. Attach a texture to the first color attachment of the FBO. For more information on how to do this, see Chapter 4, Rendering to a texture.

Create and assign any uniform variables needed for the shading model. Set the following uniforms defined in the fragment shader:

  • Width: The width of the viewport in pixels

  • Height: The height of the viewport in pixels...