Shader "Unlit/ForwardRendering" { Properties { } SubShader { Tags{ "RenderType" = "Opaque" } LOD 100 //第一个重要的平行光,计算环境光和自发光 Pass { Tags{ "LightMode" = "ForwardBase" } CGPROGRAM #pragma multi_compile_fwdbase #pragma vertex vert #pragma fragment frag #include "UnityCG.cginc" #include "Lighting.cginc" #include "AutoLight.cginc" struct appdata { float4 vertex : POSITION; float3 normal:NORMAL; }; struct v2f { float4 vertex : SV_POSITION; float3 worldNormal : COLOR0; SHADOW_COORDS(2) //定义一个对阴影纹理采样的坐标 }; v2f vert(appdata v) { v2f o; o.vertex = UnityObjectToClipPos(v.vertex); o.worldNormal = mul(unity_ObjectToWorld, v.normal); TRANSFER_SHADOW(o); //将采样坐标转换到屏幕空间 return o; } fixed4 frag(v2f i) : SV_Target { fixed3 ambient = UNITY_LIGHTMODEL_AMBIENT.xyz; float3 worldLightDir = normalize(_WorldSpaceLightPos0); fixed3 diffuse = _LightColor0.rgb * max(0, dot(i.worldNormal, worldLightDir)); fixed shadow = SHADOW_ATTENUATION(i); //采样 return fixed4(ambient + diffuse * shadow,1); } ENDCG } //计算其他逐像素光照 有阴影的设置 Pass { Tags{ "LightMode" = "ForwardAdd" } Blend One One //混合 CGPROGRAM #pragma multi_compile_fwdadd_fullshadows //编译为接受阴影 #pragma vertex vert #pragma fragment frag #include "UnityCG.cginc" #include "Lighting.cginc" #include "AutoLight.cginc" //unity_WorldToLight struct appdata { float4 vertex : POSITION; float3 normal:NORMAL; }; struct v2f { float4 vertex : SV_POSITION; float3 worldNormal : COLOR0; float4 worldPos :COLOR1; SHADOW_COORDS(2) //声明阴影纹理的取样坐标 }; v2f vert(appdata v) { v2f o; o.vertex = UnityObjectToClipPos(v.vertex); o.worldNormal = mul(unity_ObjectToWorld, v.normal); o.worldPos = mul(unity_ObjectToWorld, v.vertex); TRANSFER_SHADOW(o);//计算阴影纹理的取样坐标,屏幕空间 return o; } fixed4 frag(v2f i) : SV_Target { //光照方向 UnityWorldSpaceLightDir(worldPos) #ifdef USING_DIRECTIONAL_LIGHT fixed3 worldLightDir = normalize(_WorldSpaceLightPos0.xyz); #else fixed3 worldLightDir = normalize(_WorldSpaceLightPos0.xyz - i.worldPos.xyz); #endif UNITY_LIGHT_ATTENUATION(atten,i,i.worldPos.xyz);//计算阴影和光照衰减 联合在atten中 fixed3 diffuse = _LightColor0.rgb * max(0, dot(i.worldNormal, worldLightDir)) * atten; return fixed4(diffuse,1); } ENDCG } } Fallback "Diffuse" }
使用宏UNITY_LIGHT_ATTENUATION来计算阴影和光照衰减的联合,三个参数,一目了然的。通过这个宏可以统一在Base Pass和Additional Pass无差别的计算阴影和光照衰减,达到代码的一致。