一、利用偏导数，在Unity里面显示法线

// ddx ddy 计算法线
Shader "lcl/ddxddy/CalculateNormal"
{Properties{_MainTex ("Texture", 2D) = "white" {}}SubShader{Tags { "RenderType"="Opaque" }LOD 100Pass{CGPROGRAM#pragma vertex vert#pragma fragment frag// make fog work#pragma multi_compile_fog#include "UnityCG.cginc"struct appdata{float4 vertex : POSITION;float2 uv : TEXCOORD0;};struct v2f{float4 vertex : SV_POSITION;float3 worldPos : TEXCOORD0;};sampler2D _MainTex;float4 _MainTex_ST;v2f vert (appdata v){v2f o;o.vertex = UnityObjectToClipPos(v.vertex);o.worldPos = mul(unity_ObjectToWorld, v.vertex).xyz;return o;}fixed4 frag (v2f i) : SV_Target{float3 normalDir = normalize(cross(ddy(i.worldPos),ddx(i.worldPos)));return fixed4(normalDir,1);}ENDCG}}
}

kUnity Shader - ddx/ddy偏导函数测试，实现：锐化、高度图、Flat shading应用_Jave.Lin 的学习笔记-CSDN博客_unity锐化q

切线

Unity Shader - 切线空间的法线贴图应用（T2W & W2T）_Jave.Lin 的学习笔记-CSDN博客_unity 切线

法线贴图和切线空间_六天-CSDN博客_切线空间法线和对象空间法线