Ambient light shader example in the Built-In Render Pipeline
Example of a shader that uses ambient light.
Read time 1 minuteLast updated a month ago
Important
The Built-In Render Pipeline is deprecated and will be made obsolete in a future release.
It remains supported, including bug fixes and maintenance, through the full Unity 6.7 LTS lifecycle.
For more information on migration, refer to Migrating from the Built-In Render Pipeline to the Universal Render Pipeline and Render pipeline feature comparison.
A cat-like character lit using ambient lighting.
The example above does not take any ambient lighting or light probes into account. Let's fix this! It turns out we can do this by adding just a single line of code. Both ambient and light probe data is passed to shaders in Spherical Harmonics form, and ShadeSH9 function from UnityCG.cginc include file does all the work of evaluating it, given a world space normal.
Shader "Lit/Diffuse With Ambient"{ Properties { [NoScaleOffset] _MainTex ("Texture", 2D) = "white" {} } SubShader { Pass { Tags {"LightMode"="ForwardBase"} HLSLPROGRAM #pragma vertex vert #pragma fragment frag #include "UnityCG.cginc" #include "UnityLightingCommon.cginc" struct v2f { float2 uv : TEXCOORD0; half4 diff : COLOR0; float4 vertex : SV_POSITION; }; v2f vert (appdata_base v) { v2f o; o.vertex = UnityObjectToClipPos(v.vertex); o.uv = v.texcoord; half3 worldNormal = UnityObjectToWorldNormal(v.normal); half nl = max(0, dot(worldNormal, _WorldSpaceLightPos0.xyz)); o.diff = nl * _LightColor0; // the only difference from previous shader: // in addition to the diffuse lighting from the main light, // add illumination from ambient or light probes // ShadeSH9 function from UnityCG.cginc evaluates it, // using world space normal o.diff.rgb += ShadeSH9(half4(worldNormal,1)); return o; } sampler2D _MainTex; half4 frag (v2f i) : SV_Target { half4 col = tex2D(_MainTex, i.uv); col *= i.diff; return col; } ENDHLSL } }}
This shader is in fact starting to look very similar to the built-in Legacy Diffuse shader!