Unity中的Shader有3種方式：
1. surface shaders
2. vertex and fragment shaders
3. fixed function shaders
在shader tutorial中會指引你使用合適的shader類型。
不管你選擇什麼類型，shader的代碼實際上都在用ShaderLab來組織。如：
Shader "MyShader" {
Properties {
_MyTexture ("MyTexture", 2D) = "white" { }
// other properties likecolors or vectors go here as well
}
SubShader {
// here goes the 'meat' ofyour
// - surface shader or
// - vertex and program shader or
// - fixed function shader
}
SubShader {
// here goes a simplerversion of the SubShader above than can run on older graphics cards
}
}
建議先從ShaderLab的基礎概念、語法瞭解起，然後是Surface Shaders，或是vertext and fragment shaders。由於fixed functionshaders是用ShaderLab來寫的，你可以在ShaderLab中找到它們的更多信息。
下面的指南中包括大量的不同類shader的例子。爲了獲取更多特別的surface shaders，你可以從Resources section中獲取Unity內置shaders的源碼。Unity的Image Effects包包含很多有趣的vertext and fragment shaders。
同時瀏覽shader指南，檢驗shader tutorial。
Writing Surface Shaders
Surface Shader Examples
Custom Lighting models in Surface Shaders
Surface Shader Lighting Examples
Surface Shaders with DX11 Tessellation
Writing vertex and fragment shaders
Vertex and Fragment Shader Examples
Accessing shader properties in Cg
Providing vertex data to vertex programs
Built-in shader include files
Predefined shader preprocessor macros
Built-in state variables in shader programs
Making multiple shader program variants
GLSLShader Programs
ShaderLab syntax:Shader
ShaderLab syntax:Properties
ShaderLab syntax:SubShader
ShaderLab syntax:Pass
ShaderLab syntax:Color,Material,Lighting
ShaderLab syntax:Culling&Depth Testing
ShaderLab syntax:Texture Combiners
ShaderLab syntax:Fog
ShaderLab syntax:Alphatesting
ShaderLab syntax:Blending
ShaderLab syntax:Pass Tags
ShaderLab syntax:Name
ShaderLab syntax:BindChannels
ShaderLab syntax:Stencil
ShaderLab syntax:UsePass
ShaderLab syntax:GrabPass
ShaderLab syntax:SubShader Tags
ShaderLab syntax:Fallback
ShaderLab syntax:CustomEditor
ShaderLab syntax:other commands
Advanced ShaderLab topics
Unity’s Rendering Pipeline
Performance Tips when Writing Shaders
Rendering with Replaced Shaders
Custom Material Editors
Using Depth Textures
Camera’s Depth Texture
Platform Specific Rendering Differences
Shader Level of Detail
ShaderLab built-in values
原文地址：https://docs.unity3d.com/Documentation/Components/SL-Reference.html，下一步是抽時間逐個研究。
