Book Image

OpenGL Development Cookbook

By : Muhammad Mobeen Movania
Book Image

OpenGL Development Cookbook

By: Muhammad Mobeen Movania

Overview of this book

OpenGL is the leading cross-language, multi-platform API used by masses of modern games and applications in a vast array of different sectors. Developing graphics with OpenGL lets you harness the increasing power of GPUs and really take your visuals to the next level. OpenGL Development Cookbook is your guide to graphical programming techniques to implement 3D mesh formats and skeletal animation to learn and understand OpenGL. OpenGL Development Cookbook introduces you to the modern OpenGL. Beginning with vertex-based deformations, common mesh formats, and skeletal animation with GPU skinning, and going on to demonstrate different shader stages in the graphics pipeline. OpenGL Development Cookbook focuses on providing you with practical examples on complex topics, such as variance shadow mapping, GPU-based paths, and ray tracing. By the end you will be familiar with the latest advanced GPU-based volume rendering techniques.
Table of Contents (15 chapters)
OpenGL Development Cookbook
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Implementing per-fragment directional light


In this recipe, we will now implement directional light. The only difference between a point light and a directional light is that in the case of the directional light source, there is no position, however, there is direction, as shown in the following figure.

The figure compares directional and point light sources. For a point light source (left-hand side image), the light vector at each vertex is variable, depending on the relative positioning of the vertex with respect to the point light source. For directional light source (right-hand side image), all of the light vectors at vertices are the same and they all point in the direction of the directional light source.

Getting started

We will build on the geometry handling code from the per-fragment lighting recipe, but, instead of the pulsating cubes, we will now render a single cube with a sphere. The code for this recipe is contained in the Chapter4/DirectionalLight folder. The same code also works...