Hair sorting passes

ScriptableRenderPipeline/LightweightPipeline/LWRP/LightweightPipeline.cs

         private static readonly ShaderPassName m_UnlitPassName = new ShaderPassName("SRPDefaultUnlit"); // Renders all shaders without a lightmode tag
         private static readonly ShaderPassName m_DebugViewPass = new ShaderPassName("DebugView");
 
+        //TLS pass names
+        private static readonly ShaderPassName m_TransparentBackfaceName  = new ShaderPassName("TransparentBackFace");
+        private static readonly ShaderPassName m_TransparentFrontfaceName = new ShaderPassName("TransparentFrontFace");
+
         // Legacy pass names
         public static readonly ShaderPassName s_AlwaysName = new ShaderPassName("Always");
         public static readonly ShaderPassName s_ForwardBaseName = new ShaderPassName("ForwardBase");
             };
 
             context.DrawRenderers(m_CullResults.visibleRenderers, ref transparentSettings, transparentFilterSettings);
+
+            //The Last Stand: Hair Transparency Sorting
+            //#############################################################################
+            //#############################################################################
+            
+            //Transparent backfacing hair cards.
+            var transparentBackFaceSettings = new DrawRendererSettings(m_CurrCamera, m_TransparentBackfaceName);
+            transparentBackFaceSettings.sorting.flags = SortFlags.CommonOpaque;
+            transparentBackFaceSettings.rendererConfiguration = config;
+            
+            var transparentBackFaceFilterSettings = new FilterRenderersSettings(true)
+            {
+                renderQueueRange = RenderQueueRange.opaque
+            };
+
+            context.DrawRenderers(m_CullResults.visibleRenderers, ref transparentBackFaceSettings, transparentBackFaceFilterSettings);
+
+            //Transparent frontfacing hair cards.
+             var transparentFrontFaceSettings = new DrawRendererSettings(m_CurrCamera, m_TransparentFrontfaceName);
+            transparentFrontFaceSettings.sorting.flags = SortFlags.CommonOpaque;
+            transparentFrontFaceSettings.rendererConfiguration = config;
+            
+            var transparentFrontFaceFilterSettings = new FilterRenderersSettings(true)
+            {
+                renderQueueRange = RenderQueueRange.opaque
+            };
+
+            context.DrawRenderers(m_CullResults.visibleRenderers, ref transparentFrontFaceSettings, transparentFrontFaceFilterSettings);
+            //#############################################################################
+            //#############################################################################
 
             // Render objects that did not match any shader pass with error shader
             RenderObjectsWithError(ref context, transparentFilterSettings, SortFlags.None);

ScriptableRenderPipeline/LightweightPipeline/LWRP/Shaders/Hair/LightweightHair.shader

             Tags{"LightMode" = "LightweightForward"}
 
             Blend[_SrcBlend][_DstBlend]
-            ZWrite[_ZWrite]
+            ZWrite On
+            ZTest Less
             Cull[_Cull]
 
             HLSLPROGRAM
             #pragma shader_feature _SPECGLOSSMAP
 
             #include "LWRP/ShaderLibrary/LightweightPassMeta.hlsl"
+            ENDHLSL
+        }
+
+        
+        Pass
+        {
+            Tags {"LightMode" = "TransparentBackFace"}
+
+            Blend SrcAlpha OneMinusSrcAlpha
+            ZWrite Off
+            ZTest Less
+            Cull Front
+
+            HLSLPROGRAM
+            // Required to compile gles 2.0 with standard SRP library
+            // All shaders must be compiled with HLSLcc and currently only gles is not using HLSLcc by default
+            #pragma prefer_hlslcc gles
+            #pragma target 3.0
+
+            // -------------------------------------
+            // Material Keywords
+            #pragma shader_feature _NORMALMAP
+            //#pragma shader_feature _ALPHATEST_ON 
+            #pragma shader_feature _ALPHAPREMULTIPLY_ON
+            #pragma shader_feature _EMISSION
+            #pragma shader_feature _METALLICSPECGLOSSMAP
+            #pragma shader_feature _SMOOTHNESS_TEXTURE_ALBEDO_CHANNEL_A
+            #pragma shader_feature _OCCLUSIONMAP
+
+            #pragma shader_feature _SPECULARHIGHLIGHTS_OFF
+            #pragma shader_feature _GLOSSYREFLECTIONS_OFF
+            #pragma shader_feature _SPECULAR_SETUP
+
+            #pragma shader_feature _TWO_SIDED
+            #pragma shader_feature _HAIR_RECEIVE_SHADOWS
+
+            // -------------------------------------
+            // Lightweight Pipeline keywords
+            #pragma multi_compile _ _ADDITIONAL_LIGHTS
+            #pragma multi_compile _ _VERTEX_LIGHTS
+            #pragma multi_compile _ _MIXED_LIGHTING_SUBTRACTIVE
+            #pragma multi_compile _ FOG_LINEAR FOG_EXP2
+
+            // -------------------------------------
+            // Unity defined keywords
+            #pragma multi_compile _ DIRLIGHTMAP_COMBINED
+            #pragma multi_compile _ LIGHTMAP_ON
+
+            //--------------------------------------
+            // GPU Instancing
+            #pragma multi_compile_instancing
+
+            #pragma vertex LitPassVertex
+            #pragma fragment LitPassFragment
+
+            #include "LightweightPassLit.hlsl"
+            ENDHLSL
+        }
+
+        Pass
+        {
+            Tags {"LightMode" = "TransparentFrontFace"}
+
+            Blend SrcAlpha OneMinusSrcAlpha
+            ZWrite On
+            ZTest Less
+            Cull Back
+
+            HLSLPROGRAM
+            // Required to compile gles 2.0 with standard SRP library
+            // All shaders must be compiled with HLSLcc and currently only gles is not using HLSLcc by default
+            #pragma prefer_hlslcc gles
+            #pragma target 3.0
+
+            // -------------------------------------
+            // Material Keywords
+            #pragma shader_feature _NORMALMAP
+            //#pragma shader_feature _ALPHATEST_ON 
+            #pragma shader_feature _ALPHAPREMULTIPLY_ON
+            #pragma shader_feature _EMISSION
+            #pragma shader_feature _METALLICSPECGLOSSMAP
+            #pragma shader_feature _SMOOTHNESS_TEXTURE_ALBEDO_CHANNEL_A
+            #pragma shader_feature _OCCLUSIONMAP
+
+            #pragma shader_feature _SPECULARHIGHLIGHTS_OFF
+            #pragma shader_feature _GLOSSYREFLECTIONS_OFF
+            #pragma shader_feature _SPECULAR_SETUP
+
+            #pragma shader_feature _TWO_SIDED
+            #pragma shader_feature _HAIR_RECEIVE_SHADOWS
+
+            // -------------------------------------
+            // Lightweight Pipeline keywords
+            #pragma multi_compile _ _ADDITIONAL_LIGHTS
+            #pragma multi_compile _ _VERTEX_LIGHTS
+            #pragma multi_compile _ _MIXED_LIGHTING_SUBTRACTIVE
+            #pragma multi_compile _ FOG_LINEAR FOG_EXP2
+
+            // -------------------------------------
+            // Unity defined keywords
+            #pragma multi_compile _ DIRLIGHTMAP_COMBINED
+            #pragma multi_compile _ LIGHTMAP_ON
+
+            //--------------------------------------
+            // GPU Instancing
+            #pragma multi_compile_instancing
+
+            #pragma vertex LitPassVertex
+            #pragma fragment LitPassFragment
+
+            #include "LightweightPassLit.hlsl"
             ENDHLSL
         }