更新

Assets/OtherPlugins/GraphicsCat/Modules/LitPlus/Shaders/Includes/Passes/ShadowCasterPass.hlsl

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+#pragma once
+
+#include "Packages/com.unity.render-pipelines.core/ShaderLibrary/CommonMaterial.hlsl"
+#include "Packages/com.unity.render-pipelines.universal/ShaderLibrary/Shadows.hlsl"
+
+#include "Includes/Common/Input.hlsl"
+
+// Cutout and transparent objects need an Alpha value; enable this define to get Alpha value
+#if defined(_ALPHATEST_ON) || defined(_SURFACE_TYPE_TRANSPARENT)
+    #define ALPHA 1
+#endif
+
+// Whether to use dither mask to sparsify transparent areas of ShadowMap; when generating screen space ShadowMap, invert to calculate transparent results
+// UNITY_USE_DITHER_MASK_FOR_ALPHABLENDED_SHADOWS is determined by TierSettings.semitransparentShadows
+#if defined(_SURFACE_TYPE_TRANSPARENT) && defined(UNITY_USE_DITHER_MASK_FOR_ALPHABLENDED_SHADOWS)
+    #define USE_DITHER_MASK 1
+#endif
+
+sampler3D _DitherMaskLOD;
+full3 _LightDirection;
+
+struct Attributes
+{
+    full4 positionOS : POSITION;
+    half3 normalOS : NORMAL;
+    half4 tangentOS : TANGENT;
+    full2 uv : TEXCOORD0;
+    UNITY_VERTEX_INPUT_INSTANCE_ID
+};
+
+struct Varyings
+{
+    full4 positionCS : SV_POSITION;
+    full2 uv : TEXCOORD0; // Transparent shadows need to sample main texture data, so UV is required
+};
+
+full4 GetShadowPositionHClip(Attributes input)
+{
+    full3 positionWS = TransformObjectToWorld(input.positionOS.xyz);
+    full3 normalWS = TransformObjectToWorldNormal(input.normalOS);
+
+    full4 positionCS = TransformWorldToHClip(ApplyShadowBias(positionWS, normalWS, _LightDirection));
+
+    #if UNITY_REVERSED_Z
+    {
+        positionCS.z = min(positionCS.z, positionCS.w * UNITY_NEAR_CLIP_VALUE);
+    }
+    #else
+    {
+        positionCS.z = max(positionCS.z, positionCS.w * UNITY_NEAR_CLIP_VALUE);
+    }
+    #endif
+
+    return positionCS;
+}
+
+void VertexShadowCaster(Attributes input, out Varyings output)
+{
+    UNITY_SETUP_INSTANCE_ID(input);
+    output.positionCS = GetShadowPositionHClip(input);
+    output.uv = TRANSFORM_TEX(input.uv, _BaseMap);
+}
+
+half4 FragmentShadowCaster(Varyings input) : SV_Target
+{
+    ApplyLODCrossFade(input.positionCS.xy);
+
+    #if defined(ALPHA)
+    {
+        half alpha = tex2D(_BaseMap, input.uv).a * _BaseColor.a;
+
+        // Cutout is simple; discard pixels outside threshold
+        #if defined(_ALPHATEST_ON)
+            clip (alpha - _Cutoff);
+        #endif
+
+        // Fade or Transparent
+        #if defined(_SURFACE_TYPE_TRANSPARENT)
+        {
+            #if defined(USE_DITHER_MASK)
+            {
+                // Apply dither sparsification
+                // Use dither mask for alpha blended shadows, based on pixel position xy and alpha level. 
+                // Our dither texture is 4x4x16.
+                half3 vpos = input.positionCS.xyz / input.positionCS.w;
+                half alphaRef = tex3D(_DitherMaskLOD, half3(vpos.xy * 0.25, alpha * 0.9375)).a;
+                clip(alphaRef - 0.01);
+            }
+            #else  
+            {
+                // Without dithering, it's similar to Cutout
+                clip(alpha - _Cutoff);
+            }
+            #endif
+        }
+        #endif
+    }
+    #endif
+
+    return 0;
+}