﻿Shader "Lux URP/Lit Extended"
{
    Properties
    {

        _Rim("Enable Rim Lighting", Float) = 0
        _RimColor("Rim Color", Color) = (0.5,0.5,0.5,1)
        _RimPower("Rim Power", Float) = 2
        _RimMinPower("Rim Min Power", Float) = 1
        _RimFrequency("Rim Frequency", Float) = 0
        _RimPerPositionFrequency("Rim Per PositionFrequency", Range(0.0, 1.0)) = 1


        [Enum(UnityEngine.Rendering.CompareFunction)] _ZTest ("ZTest", Int) = 4

        _Stencil ("Stencil ID", Int) = 2
        [Enum(UnityEngine.Rendering.CompareFunction)] _StencilComp ("Stencil Comparison", Int) = 8 // always
        [Enum(UnityEngine.Rendering.StencilOp)] _StencilOp ("Stencil Operation", Int) = 2 // 2 = replace
        [Enum(UnityEngine.Rendering.StencilOp)] _StencilFail ("Stencil Fail", Int) = 0
        [Enum(UnityEngine.Rendering.StencilOp)] _StencilZFail ("Stencil ZFail", Int) = 2
        [IntRange] _ReadMask ("Read Mask", Range (0, 255)) = 255
        [IntRange] _WriteMask ("Write Mask", Range (0, 255)) = 255


        // Specular vs Metallic workflow
        [HideInInspector] _WorkflowMode("WorkflowMode", Float) = 1.0
        
        [MainColor] _BaseColor("Color", Color) = (0.5,0.5,0.5,1)
        [MainTexture] _BaseMap("Albedo", 2D) = "white" {}

        _Cutoff("Alpha Cutoff", Range(0.0, 1.0)) = 0.5

        _Smoothness("Smoothness", Range(0.0, 1.0)) = 0.5
        _GlossMapScale("Smoothness Scale", Range(0.0, 1.0)) = 1.0
        _SmoothnessTextureChannel("Smoothness texture channel", Float) = 0

        [Gamma] _Metallic("Metallic", Range(0.0, 1.0)) = 0.0
        _MetallicGlossMap("Metallic", 2D) = "white" {}

        _SpecColor("Specular", Color) = (0.2, 0.2, 0.2)
        _SpecGlossMap("Specular", 2D) = "white" {}

        [ToggleOff] _SpecularHighlights("Specular Highlights", Float) = 1.0
        [ToggleOff] _EnvironmentReflections("Environment Reflections", Float) = 1.0

        _BumpScale("Scale", Float) = 1.0
        _BumpMap("Normal Map", 2D) = "bump" {}

        _OcclusionStrength("Strength", Range(0.0, 1.0)) = 1.0
        _OcclusionMap("Occlusion", 2D) = "white" {}

        _EmissionColor("Color", Color) = (0,0,0)
        _EmissionMap("Emission", 2D) = "white" {}

        // Blending state
        [HideInInspector] _Surface("__surface", Float) = 0.0
        [HideInInspector] _Blend("__blend", Float) = 0.0
        [HideInInspector] _AlphaClip("__clip", Float) = 0.0
        [HideInInspector] _SrcBlend("__src", Float) = 1.0
        [HideInInspector] _DstBlend("__dst", Float) = 0.0
        [HideInInspector] _ZWrite("__zw", Float) = 1.0
        [HideInInspector] _Cull("__cull", Float) = 2.0

        _ReceiveShadows("Receive Shadows", Float) = 1.0        
        // Editmode props
        [HideInInspector] _QueueOffset("Queue offset", Float) = 0.0
        
        // ObsoleteProperties
        [HideInInspector] _MainTex("BaseMap", 2D) = "white" {}
        [HideInInspector] _Color("Base Color", Color) = (0.5, 0.5, 0.5, 1)
        [HideInInspector] _GlossMapScale("Smoothness", Float) = 0.0
        [HideInInspector] _Glossiness("Smoothness", Float) = 0.0
        [HideInInspector] _GlossyReflections("EnvironmentReflections", Float) = 0.0
    }

    SubShader
    {
        // Lightweight Pipeline tag is required. If Lightweight render pipeline is not set in the graphics settings
        // this Subshader will fail. One can add a subshader below or fallback to Standard built-in to make this
        // material work with both Lightweight Render Pipeline and Builtin Unity Pipeline
        Tags{
            "RenderType" = "Opaque"
            "RenderPipeline" = "UniversalPipeline"
            "IgnoreProjector" = "True"
        }
        LOD 300

        // ------------------------------------------------------------------
        //  Forward pass. Shades all light in a single pass. GI + emission + Fog
        Pass
        {
            // Lightmode matches the ShaderPassName set in LightweightRenderPipeline.cs. SRPDefaultUnlit and passes with
            // no LightMode tag are also rendered by Lightweight Render Pipeline
            Name "ForwardLit"
            Tags{"LightMode" = "UniversalForward"}

            Stencil {
                Ref   [_Stencil]
                ReadMask [_ReadMask]
                WriteMask [_WriteMask]
                Comp  [_StencilComp]
                Pass  [_StencilOp]
                Fail  [_StencilFail]
                ZFail [_StencilZFail]
                //replace
            }

            Blend[_SrcBlend][_DstBlend]
            ZTest [_ZTest]
            ZWrite[_ZWrite]
            Cull[_Cull]

            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 exclude_renderers d3d11_9x
            #pragma target 2.0

            // -------------------------------------
            // 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 _ENVIRONMENTREFLECTIONS_OFF
            #pragma shader_feature _SPECULAR_SETUP
            #pragma shader_feature _RECEIVE_SHADOWS_OFF

            #pragma shader_feature_local _RIMLIGHTING

            // -------------------------------------
            // Lightweight Pipeline keywords
            #pragma multi_compile _ _MAIN_LIGHT_SHADOWS
            #pragma multi_compile _ _MAIN_LIGHT_SHADOWS_CASCADE
            #pragma multi_compile _ _ADDITIONAL_LIGHTS_VERTEX _ADDITIONAL_LIGHTS
            #pragma multi_compile _ _ADDITIONAL_LIGHT_SHADOWS
            #pragma multi_compile _ _SHADOWS_SOFT
            #pragma multi_compile _ _MIXED_LIGHTING_SUBTRACTIVE

            // -------------------------------------
            // Unity defined keywords
            #pragma multi_compile _ DIRLIGHTMAP_COMBINED
            #pragma multi_compile _ LIGHTMAP_ON
            #pragma multi_compile_fog

            //--------------------------------------
            // GPU Instancing
            #pragma multi_compile_instancing
            
            #pragma vertex LitPassVertex
            #pragma fragment LitPassFragmentRim

            #include "Includes/Lux URP Lit Extended Inputs.hlsl"
            #include "Packages/com.unity.render-pipelines.universal/Shaders/LitForwardPass.hlsl"

            half4 LitPassFragmentRim(Varyings input) : SV_Target
            {
                UNITY_SETUP_INSTANCE_ID(input);
                UNITY_SETUP_STEREO_EYE_INDEX_POST_VERTEX(input);

                SurfaceData surfaceData;
                InitializeStandardLitSurfaceData(input.uv, surfaceData);

                InputData inputData;
                InitializeInputData(input, surfaceData.normalTS, inputData);

                #ifdef _NORMALMAP
                    half3 viewDirWS = half3(input.normalWS.w, input.tangentWS.w, input.bitangentWS.w);
                #else
                    half3 viewDirWS = input.viewDirWS;
                #endif

                #if defined(_RIMLIGHTING)
                    half rim = saturate(1.0h - saturate( dot(inputData.normalWS, normalize(viewDirWS)) ) );
                    half power = _RimPower;
                    UNITY_BRANCH if(_RimFrequency > 0 ) {
                        half perPosition = lerp(0.0h, 1.0h, dot(1.0h, frac(UNITY_MATRIX_M._m03_m13_m23) * 2.0h - 1.0h ) * _RimPerPositionFrequency ) * 3.1416h;
                        power = lerp(power, _RimMinPower, (1.0h + sin(_Time.y * _RimFrequency + perPosition) ) * 0.5h );
                    }
                    surfaceData.emission += pow(rim, power) * _RimColor.rgb * _RimColor.a;
                #endif

                half4 color = LightweightFragmentPBR(inputData, surfaceData.albedo, surfaceData.metallic, surfaceData.specular, surfaceData.smoothness, surfaceData.occlusion, surfaceData.emission, surfaceData.alpha);

                color.rgb = MixFog(color.rgb, inputData.fogCoord);
                return color;
            }
            ENDHLSL
        }

        Pass
        {
            Name "ShadowCaster"
            Tags{"LightMode" = "ShadowCaster"}

            ZWrite On
            //ZTest LEqual
            ZTest [_ZTest]
            Cull[_Cull]

            HLSLPROGRAM
            // Required to compile gles 2.0 with standard srp library
            #pragma prefer_hlslcc gles
            #pragma exclude_renderers d3d11_9x
            #pragma target 2.0

            // -------------------------------------
            // Material Keywords
            #pragma shader_feature _ALPHATEST_ON

            //--------------------------------------
            // GPU Instancing
            #pragma multi_compile_instancing
            #pragma shader_feature _SMOOTHNESS_TEXTURE_ALBEDO_CHANNEL_A

            #pragma vertex ShadowPassVertex
            #pragma fragment ShadowPassFragment

            #include "Includes/Lux URP Lit Extended Inputs.hlsl"
            #include "Packages/com.unity.render-pipelines.universal/Shaders/ShadowCasterPass.hlsl"
            ENDHLSL
        }

        Pass
        {
            Name "DepthOnly"
            Tags{"LightMode" = "DepthOnly"}

            ZWrite On
            ZTest [_ZTest]
            ColorMask 0
            Cull[_Cull]

            HLSLPROGRAM
            // Required to compile gles 2.0 with standard srp library
            #pragma prefer_hlslcc gles
            #pragma exclude_renderers d3d11_9x
            #pragma target 2.0

            #pragma vertex DepthOnlyVertex
            #pragma fragment DepthOnlyFragment

            // -------------------------------------
            // Material Keywords
            #pragma shader_feature _ALPHATEST_ON
            #pragma shader_feature _SMOOTHNESS_TEXTURE_ALBEDO_CHANNEL_A

            //--------------------------------------
            // GPU Instancing
            #pragma multi_compile_instancing

            #include "Includes/Lux URP Lit Extended Inputs.hlsl"
            #include "Packages/com.unity.render-pipelines.universal/Shaders/DepthOnlyPass.hlsl"
            ENDHLSL
        }

        // This pass it not used during regular rendering, only for lightmap baking.
        Pass
        {
            Name "Meta"
            Tags{"LightMode" = "Meta"}

            Cull Off

            HLSLPROGRAM
            // Required to compile gles 2.0 with standard srp library
            #pragma prefer_hlslcc gles
            #pragma exclude_renderers d3d11_9x

            #pragma vertex UniversalVertexMeta
            #pragma fragment UniversalFragmentMeta

            #pragma shader_feature _SPECULAR_SETUP
            #pragma shader_feature _EMISSION
            #pragma shader_feature _METALLICSPECGLOSSMAP
            #pragma shader_feature _ALPHATEST_ON
            #pragma shader_feature _ _SMOOTHNESS_TEXTURE_ALBEDO_CHANNEL_A

            #pragma shader_feature _SPECGLOSSMAP

            #include "Includes/Lux URP Lit Extended Inputs.hlsl"
            #include "Packages/com.unity.render-pipelines.universal/Shaders/LitMetaPass.hlsl"

            ENDHLSL
        }

    }
    FallBack "Hidden/InternalErrorShader"
    CustomEditor "UnityEditor.Rendering.URP.ShaderGUI.LitExtendedShader"
}