Unity shader实现高斯模糊效果

Shader "Custom/GaoSiMoHu"{ Properties { _MainTex ("Texture", 2D) = "white" {} _BlurSize("Blur size",Float)=1.0 } SubShader { ZTest Always cull off ZWrite off CGINCLUDE//这个可以使其他pass块都可以使用，而不用在两个pass里都写，减少了写的次数 sampler2D _MainTex; half4 _MainTex_TexelSize; float _BlurSize; struct v2f{  float4 pos:SV_POSITION;  half2 uv[5]:TEXCOORD0; }; fixed4 fragBlur(v2f i):SV_Target{  float weight[3]={  0.4026,  0.2442,  0.0545  };  fixed3 sum = tex2D(_MainTex,i.uv[0]).rgb * weight[0];  for(int it = 1; it < 3; it++){  sum += tex2D(_MainTex,i.uv[it]).rgb * weight[it];  sum += tex2D(_MainTex,i.uv[2 * it]).rgb * weight[it];  }  return fixed4(sum,1.0); } ENDCG Pass{  NAME "GAUSSIAN_BLUR_VERTICAL"//这个pass的唯一名字，可以在其他地方调用，usepass + 名字  CGPROGRAM  #pragma vertex vertlurVertical  #pragma fragment fragBlur  #include "UnityCG.cginc"    v2f vertlurVertical(appdata_img v){  v2f o;  o.pos = UnityObjectToClipPos(v.vertex);  half2 uv = v.texcoord;  o.uv[0]=uv;  o.uv[1]=uv + float2(0.0,_MainTex_TexelSize.y * 1.0) * _BlurSize;  o.uv[2]=uv - float2(0.0,_MainTex_TexelSize.y * 1.0) * _BlurSize;  o.uv[3]=uv + float2(0.0,_MainTex_TexelSize.y * 2.0) * _BlurSize;  o.uv[4]=uv - float2(0.0,_MainTex_TexelSize.y * 2.0) * _BlurSize;  return o;  }  ENDCG } Pass{  NAME "GAUSSIAN_BLUR_HORIZONTAL"  CGPROGRAM  #pragma vertex vertlurHorizontal  #pragma fragment fragBlur  #include "UnityCG.cginc"  v2f vertlurHorizontal(appdata_img v){  v2f o;  o.pos = UnityObjectToClipPos(v.vertex);  half2 uv = v.texcoord;  o.uv[0]=uv;  o.uv[1]=uv + float2(0.0,_MainTex_TexelSize.x * 1.0) * _BlurSize;  o.uv[2]=uv - float2(0.0,_MainTex_TexelSize.x * 1.0) * _BlurSize;  o.uv[3]=uv + float2(0.0,_MainTex_TexelSize.x * 2.0) * _BlurSize;  o.uv[4]=uv - float2(0.0,_MainTex_TexelSize.x * 2.0) * _BlurSize;  return o;  }  ENDCG } }}