// Shader uses custom editor to set double sided GI
// Needs _Culling to be set properly

Shader "Lux URP/Nature/Tree Creator Leaves"
{
    Properties
    {

        [Header(Surface Inputs)]
        [Space(5)]
        _Color                      ("Main Color", Color) = (1,1,1,1)
        [PowerSlider(5.0)] _Shininess ("Shininess", Range (0.01, 1)) = 0.078125
        _MainTex                    ("Base (RGB) Alpha (A)", 2D) = "white" {}
        _Cutoff                     ("Alpha cutoff", Range(0.0, 1.0)) = 0.5

        [Space(5)]
        [NoScaleOffset]
        _BumpMap                    ("Normalmap", 2D) = "bump" {}
        [NoScaleOffset]
        _GlossMap                   ("Gloss (A)", 2D) = "black" {}
        [NoScaleOffset]
        _TranslucencyMap            ("Translucency (A)", 2D) = "white" {}

        [HideInInspector] _TreeInstanceColor ("TreeInstanceColor", Vector) = (1,1,1,1)
        [HideInInspector] _TreeInstanceScale ("TreeInstanceScale", Vector) = (1,1,1,1)
        [HideInInspector] _SquashAmount ("Squash", Float) = 1

    //  Lightmapper and outline selection shader need _MainTex, _Color and _Cutoff
        
    }

    SubShader
    {
        Tags
        {
            "RenderPipeline" = "UniversalPipeline"
            "RenderType" = "TransparentCutout"
            "IgnoreProjector" = "True"
            "Queue"="AlphaTest"
        }
        LOD 100

        Pass
        {
            Name "ForwardLit"
            Tags{"LightMode" = "UniversalForward"}

            ZWrite On
            Cull Back

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

        //  Shader target needs to be 3.0 due to tex2Dlod in the vertex shader and VFACE
            #pragma target 2.0

            // -------------------------------------
            // Material Keywords
            // #define _SPECULAR_SETUP 1

            #define DUMMYSHADER

            #define _ALPHATEST_ON
            #define _NORMALMAP

            // -------------------------------------
            // 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

        //  Trees do not support lightmapping
            // #pragma multi_compile _ DIRLIGHTMAP_COMBINED
            // #pragma multi_compile _ LIGHTMAP_ON
            // #pragma multi_compile_fog


        //  Include base inputs and all other needed "base" includes
            #include "Includes/Lux URP Tree Creator Inputs.hlsl"
            #include "Includes/Lux URP Tree Creator Library.hlsl"


            #pragma vertex LitPassVertex
            #pragma fragment LitPassFragment

        //--------------------------------------
        //  Vertex shader


            VertexOutput LitPassVertex(VertexInput input)
            {
                VertexOutput output = (VertexOutput)0;
                UNITY_SETUP_INSTANCE_ID(input);
                UNITY_TRANSFER_INSTANCE_ID(input, output);
                UNITY_INITIALIZE_VERTEX_OUTPUT_STEREO(output);

                TreeVertLeaf(input);

                VertexPositionInputs vertexInput; // 
                vertexInput = GetVertexPositionInputs(input.positionOS.xyz);
                VertexNormalInputs normalInput = GetVertexNormalInputs(input.normalOS, input.tangentOS);

                half3 viewDirWS = GetCameraPositionWS() - vertexInput.positionWS;
                half3 vertexLight = VertexLighting(vertexInput.positionWS, normalInput.normalWS);
                half fogFactor = ComputeFogFactor(vertexInput.positionCS.z);

                output.uv = TRANSFORM_TEX(input.texcoord, _MainTex);
                
                output.normalWS = half4(normalInput.normalWS, viewDirWS.x);
                output.tangentWS = half4(normalInput.tangentWS, viewDirWS.y);
                output.bitangentWS = half4(normalInput.bitangentWS, viewDirWS.z);

                OUTPUT_LIGHTMAP_UV(input.lightmapUV, unity_LightmapST, output.lightmapUV);
                OUTPUT_SH(output.normalWS.xyz, output.vertexSH);
                
                output.fogFactorAndVertexLight = half4(fogFactor, vertexLight);

                #if defined(REQUIRES_WORLD_SPACE_POS_INTERPOLATOR)
                    output.positionWS = vertexInput.positionWS;
                #endif

                #if defined(REQUIRES_VERTEX_SHADOW_COORD_INTERPOLATOR)
                    output.shadowCoord = GetShadowCoord(vertexInput);
                #endif

                output.positionCS = vertexInput.positionCS;

                output.color = input.color;

                #if defined(BILLBOARD_FACE_CAMERA_POS) && defined(_ENABLEDITHERING)
                    output.screenPos = ComputeScreenPos(output.positionCS);
                #endif

                return output;
            }

        //--------------------------------------
        //  Fragment shader and functions

            inline void InitializeSurfaceData(
                float2 uv,
                out SurfaceDescription outSurfaceData)
            {

                half4 albedoAlpha = SampleAlbedoAlpha(uv.xy, TEXTURE2D_ARGS(_MainTex, sampler_MainTex));
                outSurfaceData.alpha = Alpha(albedoAlpha.a, half4(1,1,1,1), _Cutoff);
                outSurfaceData.albedo = albedoAlpha.rgb; // * _Color.rgb;
            
            //  Normal
                outSurfaceData.normalTS = SampleNormal(uv, TEXTURE2D_ARGS(_BumpMap, sampler_BumpMap), 5);

                outSurfaceData.specular = _Shininess;
                
                outSurfaceData.occlusion = 1;

            //  Transmission
                half4 maskSample = SAMPLE_TEXTURE2D(_TranslucencyMap, sampler_TranslucencyMap, uv);
                outSurfaceData.translucency = maskSample.b;
            //  Gloss
                outSurfaceData.gloss = SAMPLE_TEXTURE2D(_GlossMap, sampler_GlossMap, uv).a;
            }

            void InitializeInputData(VertexOutput input, half3 normalTS, out InputData inputData)
            {
                inputData = (InputData)0;
                #if defined(REQUIRES_WORLD_SPACE_POS_INTERPOLATOR)
                    inputData.positionWS = input.positionWS;
                #endif
                
                half3 viewDirWS = half3(input.normalWS.w, input.tangentWS.w, input.bitangentWS.w);
                inputData.normalWS = TransformTangentToWorld(normalTS, half3x3(input.tangentWS.xyz, input.bitangentWS.xyz, input.normalWS.xyz));

                inputData.normalWS = NormalizeNormalPerPixel(inputData.normalWS);
                viewDirWS = SafeNormalize(viewDirWS);
                inputData.viewDirectionWS = viewDirWS;

                #if defined(REQUIRES_VERTEX_SHADOW_COORD_INTERPOLATOR)
                    inputData.shadowCoord = input.shadowCoord;
                #elif defined(MAIN_LIGHT_CALCULATE_SHADOWS)
                    inputData.shadowCoord = TransformWorldToShadowCoord(inputData.positionWS);
                #else
                    inputData.shadowCoord = float4(0, 0, 0, 0);
                #endif
                
                inputData.fogCoord = input.fogFactorAndVertexLight.x;
                inputData.vertexLighting = input.fogFactorAndVertexLight.yzw;
                inputData.bakedGI = SAMPLE_GI(input.lightmapUV, input.vertexSH, inputData.normalWS);
            }

            half4 LitPassFragment(VertexOutput input) : SV_Target
            {
                UNITY_SETUP_INSTANCE_ID(input);
                UNITY_SETUP_STEREO_EYE_INDEX_POST_VERTEX(input);

            //  Get the surface description
                SurfaceDescription surfaceData;
                InitializeSurfaceData(input.uv, surfaceData);

            //  Apply tree color and occlusion
                surfaceData.albedo *= input.color.rgb;
                surfaceData.occlusion = input.color.a;

            //  Prepare surface data (like bring normal into world space and get missing inputs like gi)
                InputData inputData;
                InitializeInputData(input, surfaceData.normalTS, inputData);

            //  Apply lighting
                half4 color = LuxURPTreeLeafFragmentPBR (
                    inputData, 
                    surfaceData.albedo,
                    surfaceData.specular, 
                    surfaceData.gloss, 
                    surfaceData.occlusion, 
                    surfaceData.alpha,
                    half2(surfaceData.translucency, _TranslucencyViewDependency),
                    _TranslucencyColor.rgb,
                    UNITY_ACCESS_INSTANCED_PROP(Props, _SquashAmount),
                    1.0h // ShadowStrength
                );   

            //  Add fog
                color.rgb = MixFog(color.rgb, inputData.fogCoord);
                return color;
            }

            ENDHLSL
        }

    //  End Passes -----------------------------------------------------
    
    }
    FallBack "Hidden/InternalErrorShader"
    Dependency "OptimizedShader" = "Lux URP/Nature/Tree Creator Leaves Optimized"
}