Shader "Lightweight Render Pipeline/Terrain/Lit"
{
    Properties
    {
        // set by terrain engine
        [HideInInspector] _Control("Control (RGBA)", 2D) = "red" {}
        [HideInInspector] _Splat3("Layer 3 (A)", 2D) = "grey" {}
        [HideInInspector] _Splat2("Layer 2 (B)", 2D) = "grey" {}
        [HideInInspector] _Splat1("Layer 1 (G)", 2D) = "grey" {}
        [HideInInspector] _Splat0("Layer 0 (R)", 2D) = "grey" {}
        [HideInInspector] _Normal3("Normal 3 (A)", 2D) = "bump" {}
        [HideInInspector] _Normal2("Normal 2 (B)", 2D) = "bump" {}
        [HideInInspector] _Normal1("Normal 1 (G)", 2D) = "bump" {}
        [HideInInspector] _Normal0("Normal 0 (R)", 2D) = "bump" {}
        [HideInInspector][Gamma] _Metallic0("Metallic 0", Range(0.0, 1.0)) = 0.0
        [HideInInspector][Gamma] _Metallic1("Metallic 1", Range(0.0, 1.0)) = 0.0
        [HideInInspector][Gamma] _Metallic2("Metallic 2", Range(0.0, 1.0)) = 0.0
        [HideInInspector][Gamma] _Metallic3("Metallic 3", Range(0.0, 1.0)) = 0.0
        [HideInInspector] _Smoothness0("Smoothness 0", Range(0.0, 1.0)) = 0.5
        [HideInInspector] _Smoothness1("Smoothness 1", Range(0.0, 1.0)) = 0.5
        [HideInInspector] _Smoothness2("Smoothness 2", Range(0.0, 1.0)) = 0.5
        [HideInInspector] _Smoothness3("Smoothness 3", Range(0.0, 1.0)) = 0.5

        // used in fallback on old cards & base map
        [HideInInspector] _MainTex("BaseMap (RGB)", 2D) = "grey" {}
        [HideInInspector] _Color("Main Color", Color) = (1,1,1,1)

        // TODO: Implement ShaderGUI for the shader and display the checkbox only when instancing is enabled.
        [Toggle(_TERRAIN_INSTANCED_PERPIXEL_NORMAL)] _TERRAIN_INSTANCED_PERPIXEL_NORMAL("Enable Instanced Per-pixel Normal", Float) = 0
    }

    SubShader
    {
        Tags { "Queue" = "Geometry-100" "RenderType" = "Opaque" "RenderPipeline" = "LightweightPipeline" "IgnoreProjector" = "False"}

        Pass
        {
            Name "ForwardLit"
            Tags { "LightMode" = "LightweightForward" }
            HLSLPROGRAM
            // Required to compile gles 2.0 with standard srp library
            #pragma prefer_hlslcc gles
            #pragma exclude_renderers d3d11_9x
            #pragma target 3.0

            #pragma vertex SplatmapVert
            #pragma fragment SplatmapFragment

            #define _METALLICSPECGLOSSMAP 1
            #define _SMOOTHNESS_TEXTURE_ALBEDO_CHANNEL_A 1

            // -------------------------------------
            // 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
            #pragma multi_compile_instancing
            #pragma instancing_options assumeuniformscaling nomatrices nolightprobe nolightmap

            #pragma shader_feature _NORMALMAP
            // Sample normal in pixel shader when doing instancing
            #pragma shader_feature _TERRAIN_INSTANCED_PERPIXEL_NORMAL

            #include "TerrainLitInput.hlsl"
            #include "TerrainLitPasses.hlsl"
            ENDHLSL
        }

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

            ZWrite On

            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 ShadowPassVertex
            #pragma fragment ShadowPassFragment

            #pragma multi_compile_instancing
            #pragma instancing_options assumeuniformscaling nomatrices nolightprobe nolightmap

            #include "TerrainLitInput.hlsl"
            #include "TerrainLitPasses.hlsl"
            ENDHLSL
        }

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

            ZWrite On
            ColorMask 0

            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

            #pragma multi_compile_instancing
            #pragma instancing_options assumeuniformscaling nomatrices nolightprobe nolightmap

            #include "TerrainLitInput.hlsl"
            #include "TerrainLitPasses.hlsl"
            ENDHLSL
        }

        UsePass "Hidden/Nature/Terrain/Utilities/PICKING"
        UsePass "Hidden/Nature/Terrain/Utilities/SELECTION"
    }
    Dependency "AddPassShader" = "Hidden/Lightweight Render Pipeline/Terrain/Lit (Add Pass)"
    Dependency "BaseMapShader" = "Hidden/Lightweight Render Pipeline/Terrain/Lit (Base Pass)"

    Fallback "Hidden/InternalErrorShader"
}
