OpenGL Programming Guide: The Official Guide to Learning OpenGL, Version 4.3, Eighth Edition

Lighting Introduction

The programmability of OpenGL shaders allows virtually limitless possibilities for lighting a scene. Old-school fixed-functionality lighting models were comparatively constraining, lacking in some realism and in performance-quality trade-offs. Programmable shaders can provide far superior results, especially in the area of realism. Nevertheless, it is still important to start with an understanding of the classic lighting model that was embodied by old fixed functionality, though we will be more flexible on which shader stages do which part. This lighting model still provides the fundamentals on which most rasterization lighting techniques are based, and is a springboard for grasping the more advanced techniques.

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