Shader "Unlit/ForwardRendering" { Properties { } SubShader { Tags{ "RenderType" = "Opaque" } LOD 100 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 } } Fallback "Diffuse" //这里面有个Fallback为VertexLit定义了LightMode=ShadowCaster的Pass,所以会参与阴影投射 }
接受阴影的三剑客,SHADOW_COORDS、TRANSFER_SHADOW、SHADOW_ATTENUATION,注意这些宏使用了上下文的变量,所以这些变量名需要对应上,appdata的v的vertex,v2f的i的vertex。