Pass
{
	Tags{"LightMode" = "LightweightForward"}
	${Tags}
	${Blending}
	${Culling}
	${ZTest}
	${ZWrite}

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

	// -------------------------------------
	// Lightweight Pipeline keywords
	#pragma multi_compile _ _ADDITIONAL_LIGHTS
	#pragma multi_compile _ _VERTEX_LIGHTS
	#pragma multi_compile _ _MIXED_LIGHTING_SUBTRACTIVE
	#pragma multi_compile _ _SHADOWS_ENABLED

	// -------------------------------------
	// 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 vert
	#pragma fragment frag

	${Defines}

	#include "LWRP/ShaderLibrary/Core.hlsl"
	#include "LWRP/ShaderLibrary/Lighting.hlsl"
	#include "CoreRP/ShaderLibrary/Color.hlsl"
	#include "CoreRP/ShaderLibrary/UnityInstancing.hlsl"
	#include "ShaderGraphLibrary/Functions.hlsl"

	${Graph}

	struct GraphVertexOutput
    {
        float4 clipPos                : SV_POSITION;
        DECLARE_LIGHTMAP_OR_SH(lightmapUV, vertexSH, 0);
		half4 fogFactorAndVertexLight : TEXCOORD1; // x: fogFactor, yzw: vertex light
    	float4 shadowCoord            : TEXCOORD2;
        ${Interpolators}
        UNITY_VERTEX_INPUT_INSTANCE_ID
    };

    GraphVertexOutput vert (GraphVertexInput v)
	{
	    v = PopulateVertexData(v);

        GraphVertexOutput o = (GraphVertexOutput)0;

        UNITY_SETUP_INSTANCE_ID(v);
    	UNITY_TRANSFER_INSTANCE_ID(v, o);

        ${VertexShader}

		float3 lwWNormal = TransformObjectToWorldNormal(v.normal);
		float3 lwWorldPos = TransformObjectToWorld(v.vertex.xyz);
		float4 clipPos = TransformWorldToHClip(lwWorldPos);

 		// We either sample GI from lightmap or SH.
	    // Lightmap UV and vertex SH coefficients use the same interpolator ("float2 lightmapUV" for lightmap or "half3 vertexSH" for SH)
        // see DECLARE_LIGHTMAP_OR_SH macro.
	    // The following funcions initialize the correct variable with correct data
	    OUTPUT_LIGHTMAP_UV(v.texcoord1, unity_LightmapST, o.lightmapUV);
	    OUTPUT_SH(lwWNormal, o.vertexSH);

	    half3 vertexLight = VertexLighting(lwWorldPos, lwWNormal);
	    half fogFactor = ComputeFogFactor(clipPos.z);
	    o.fogFactorAndVertexLight = half4(fogFactor, vertexLight);
	    o.clipPos = clipPos;

	    #ifdef _SHADOWS_ENABLED
		#if SHADOWS_SCREEN
			o.shadowCoord = ComputeShadowCoord(clipPos);
		#else
			o.shadowCoord = TransformWorldToShadowCoord(lwWorldPos);
		#endif
		#endif
		
		return o;
	}

	half4 frag (GraphVertexOutput IN) : SV_Target
    {
    	UNITY_SETUP_INSTANCE_ID(IN);

    	${LocalPixelShader}

        SurfaceInputs surfaceInput = (SurfaceInputs)0;
        ${SurfaceInputs}

        SurfaceDescription surf = PopulateSurfaceData(surfaceInput);

		float3 Albedo = float3(0.5, 0.5, 0.5);
		float3 Specular = float3(0, 0, 0);
		float Metallic = 1;
		float3 Normal = float3(0, 0, 1);
		float3 Emission = 0;
		float Smoothness = 0.5;
		float Occlusion = 1;
		float Alpha = 1;
		float AlphaClipThreshold = 0;

        ${SurfaceOutputRemap}

		InputData inputData;
		inputData.positionWS = WorldSpacePosition;

#ifdef _NORMALMAP
	    inputData.normalWS = TangentToWorldNormal(Normal, WorldSpaceTangent, WorldSpaceBiTangent, WorldSpaceNormal);
#else
    #if !SHADER_HINT_NICE_QUALITY
        inputData.normalWS = WorldSpaceNormal;
    #else
	    inputData.normalWS = normalize(WorldSpaceNormal);
    #endif
#endif

#if !SHADER_HINT_NICE_QUALITY
	    // viewDirection should be normalized here, but we avoid doing it as it's close enough and we save some ALU.
	    inputData.viewDirectionWS = WorldSpaceViewDirection;
#else
	    inputData.viewDirectionWS = normalize(WorldSpaceViewDirection);
#endif

	    inputData.shadowCoord = IN.shadowCoord;

	    inputData.fogCoord = IN.fogFactorAndVertexLight.x;
	    inputData.vertexLighting = IN.fogFactorAndVertexLight.yzw;
	    inputData.bakedGI = SAMPLE_GI(IN.lightmapUV, IN.vertexSH, inputData.normalWS);

		half4 color = LightweightFragmentPBR(
			inputData, 
			Albedo, 
			Metallic, 
			Specular, 
			Smoothness, 
			Occlusion, 
			Emission, 
			Alpha);

		// Computes fog factor per-vertex
    	ApplyFog(color.rgb, IN.fogFactorAndVertexLight.x);

#if _AlphaClip
		clip(Alpha - AlphaClipThreshold);
#endif
		return color;
    }

	ENDHLSL
}