Introduction

Simulating the way light works is a very challenging and resource-consuming task. For many years, video games have used very simple lighting models which, despite lacking realism, were very believable. Even if most 3D engines are now using physically-based renderers, it is worth exploring some simpler techniques. The ones presented in this chapter are reasonably realistic and widely adopted on devices with low resources such as mobile phones. Understanding these simple lighting models is also essential if you want to create your own.