Materials, textures, and shaders

In this section, we will discuss, you guessed it: materials, textures, and shaders. As we have touched on this subject lightly before, we will dig in a bit deeper this time. Unity's rendering system and lighting model uses Physically Based Shading (PBS), which is a simulation between the materials in the scene and the lights. PBS, in many ways, closely imitates how lights and materials work in real life.

Materials

Materials are art assets placed on an object that give various rendering properties. A highly reflective polish job on a smooth, silver surface or a rough and rugged wooden door with moss growing on the bottom are both examples of Materials. Materials are made up of the Material component itself, shaders, and textures.

While the details of shaders are beyond the scope of this book, we do need a general overview. A shader is a small script file that tells Unity how to react to light. In real life, when light hits a surface, it does not just stop there...