Built-in shader include files

Unity contains several files that can be used by your shader programs to bring in predefined variables and helper functions. This is done by the standard #include directive, e.g.:

CGPROGRAM
// ...
#include "UnityCG.cginc"
// ...
ENDCG

Shader include files in Unity are with .cginc extension, and the built-in ones are:

• HLSLSupport.cginc - (automatically included) Helper macros and definitions for cross-platform shader compilation.
• UnityShaderVariables.cginc - (automatically included) Commonly used global variables.
• UnityCG.cginc - commonly used helper functions.
• AutoLight.cginc - lighting & shadowing functionality, e.g. surface shaders use this file internally.
• Lighting.cginc - standard surface shader lighting models; automatically included when you’re writing surface shaders.
• TerrainEngine.cginc - helper functions for Terrain & Vegetation shaders.

These files are found inside Unity application ({unity install path}/Data/CGIncludes/UnityCG.cginc on Windows, /Applications/Unity/Unity.app/Contents/CGIncludes/UnityCG.cginc on Mac), if you want to take a look at what exactly is done in any of the helper code.

HLSLSupport.cginc

This file is automatically included when compiling shaders. It declares various preprocessor macros to aid in multi-platform shader development.

UnityShaderVariables.cginc

This file is automatically included when compiling shaders. It declares various built-in global variables that are commonly used in shaders.

UnityCG.cginc

This file is often included in Unity shaders. It declares many built-in helper functions and data structures.

Data structures in UnityCG.cginc

• struct appdata_base: vertex shader input with position, normal, one texture coordinate.
• struct appdata_tan: vertex shader input with position, normal, tangent, one texture coordinate.
• struct appdata_full: vertex shader input with position, normal, tangent, vertex color and two texture coordinates.
• struct appdata_img: vertex shader input with position and one texture coordinate.