//NOTE! This file is based on Unity file "TerrainLit_Basemap.shader" which was used as a template for adding all the InTerra features.
Shader "Hidden/InTerra/HDRP/TerrainLit_Basemap_2022_2"
{
    Properties
    {
        // Following are builtin properties

        // Stencil state
        // Forward
        [HideInInspector] _StencilRef("_StencilRef", Int) = 0  // StencilUsage.Clear
        [HideInInspector] _StencilWriteMask("_StencilWriteMask", Int) = 3 // StencilUsage.RequiresDeferredLighting | StencilUsage.SubsurfaceScattering
        // GBuffer
        [HideInInspector] _StencilRefGBuffer("_StencilRefGBuffer", Int) = 2 // StencilUsage.RequiresDeferredLighting
        [HideInInspector] _StencilWriteMaskGBuffer("_StencilWriteMaskGBuffer", Int) = 3 // StencilUsage.RequiresDeferredLighting | StencilUsage.SubsurfaceScattering
        // Depth prepass
        [HideInInspector] _StencilRefDepth("_StencilRefDepth", Int) = 0 // Nothing
        [HideInInspector] _StencilWriteMaskDepth("_StencilWriteMaskDepth", Int) = 8 // StencilUsage.TraceReflectionRay

        // Blending state
        [HideInInspector] _ZWrite ("__zw", Float) = 1.0
        [HideInInspector] _CullMode("__cullmode", Float) = 2.0
        [HideInInspector] _ZTestDepthEqualForOpaque("_ZTestDepthEqualForOpaque", Int) = 4 // Less equal
        [HideInInspector] _ZTestGBuffer("_ZTestGBuffer", Int) = 4

        [HideInInspector] _TerrainHolesTexture("Holes Map (RGB)", 2D) = "white" {}

        // Caution: C# code in BaseLitUI.cs call LightmapEmissionFlagsProperty() which assume that there is an existing "_EmissionColor"
        // value that exist to identify if the GI emission need to be enabled.
        // In our case we don't use such a mechanism but need to keep the code quiet. We declare the value and always enable it.
        // TODO: Fix the code in legacy unity so we can customize the behavior for GI
        _EmissionColor("Color", Color) = (1, 1, 1)

        _MetallicTex("Metallic (RGB)", 2D) = "white" {}
        _Triplanar_MetallicAO("Metallic AO (RGB)", 2D) = "white" {}
        // HACK: GI Baking system relies on some properties existing in the shader ("_MainTex", "_Cutoff" and "_Color") for opacity handling, so we need to store our version of those parameters in the hard-coded name the GI baking system recognizes.
        _MainTex("Albedo", 2D) = "white" {}
        _Color("Color", Color) = (1,1,1,1)

        [ToggleUI] _SupportDecals("Support Decals", Float) = 1.0
        [ToggleUI] _ReceivesSSR("Receives SSR", Float) = 1.0
    }

    HLSLINCLUDE

    #pragma target 4.5
    #pragma only_renderers d3d11 playstation xboxone xboxseries vulkan metal switch

    #pragma shader_feature_local _DISABLE_DECALS
    #pragma shader_feature_local _TERRAIN_INSTANCED_PERPIXEL_NORMAL

    // InTerra Keywords
    #pragma shader_feature_local __ _TERRAIN_TRIPLANAR_ONE _TERRAIN_TRIPLANAR

    //enable GPU instancing support
    #pragma multi_compile_instancing
    #pragma instancing_options assumeuniformscaling nomatrices nolightprobe nolightmap

    #pragma multi_compile _ _ALPHATEST_ON
    #define UNITY_2022_2_OR_NEWER

    #pragma vertex Vert
    #pragma fragment Frag

    #include "Packages/com.unity.render-pipelines.high-definition/Runtime/Material/TerrainLit/TerrainLit_Basemap_Includes.hlsl"

    ENDHLSL

   SubShader
    {
        PackageRequirements { "com.unity.render-pipelines.high-definition":"[14.0.0,14.99.99]" }

        // This tags allow to use the shader replacement features
        Tags{ "RenderPipeline" = "HDRenderPipeline" "RenderType" = "Opaque" }

        // Caution: The outline selection in the editor use the vertex shader/hull/domain shader of the first pass declare. So it should not bethe  meta pass.
        Pass
        {
            Name "GBuffer"
            Tags { "LightMode" = "GBuffer" } // This will be only for opaque object based on the RenderQueue index

            Cull [_CullMode]
            ZTest [_ZTestGBuffer]

            Stencil
            {
                WriteMask [_StencilWriteMaskGBuffer]
                Ref [_StencilRefGBuffer]
                Comp Always
                Pass Replace
            }

            HLSLPROGRAM

            #pragma multi_compile _ DEBUG_DISPLAY
            #pragma multi_compile _ LIGHTMAP_ON
            #pragma multi_compile _ DIRLIGHTMAP_COMBINED
            #pragma multi_compile _ DYNAMICLIGHTMAP_ON
            #pragma multi_compile_fragment _ SHADOWS_SHADOWMASK
            #pragma multi_compile_fragment PROBE_VOLUMES_OFF PROBE_VOLUMES_L1 PROBE_VOLUMES_L2
            // Setup DECALS_OFF so the shader stripper can remove variants
            #pragma multi_compile_fragment DECALS_OFF DECALS_3RT DECALS_4RT
            #pragma multi_compile_fragment _ LIGHT_LAYERS

            #define SHADERPASS SHADERPASS_GBUFFER
            #include "InTerra_HDRP_DefinedGlobalKeywords.hlsl"
            #include "InTerra_TerrainLitTemplate.hlsl"
            #include "InTerra_TerrainLit_Basemap.hlsl"

            ENDHLSL
        }

        // Extracts information for lightmapping, GI (emission, albedo, ...)
        // This pass it not used during regular rendering.
        Pass
        {
            Name "META"
            Tags{ "LightMode" = "META" }

            Cull Off

            HLSLPROGRAM

            // Lightmap memo
            // DYNAMICLIGHTMAP_ON is used when we have an "enlighten lightmap" ie a lightmap updated at runtime by enlighten.This lightmap contain indirect lighting from realtime lights and realtime emissive material.Offline baked lighting(from baked material / light,
            // both direct and indirect lighting) will hand up in the "regular" lightmap->LIGHTMAP_ON.

            #define SHADERPASS SHADERPASS_LIGHT_TRANSPORT
            #include "InTerra_HDRP_DefinedGlobalKeywords.hlsl"
            #include "InTerra_TerrainLitTemplate.hlsl"
            #include "InTerra_TerrainLit_Basemap.hlsl"

            ENDHLSL
        }

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

            Cull[_CullMode]

            ZClip [_ZClip]
            ZWrite On
            ZTest LEqual

            ColorMask 0

            HLSLPROGRAM

            #define SHADERPASS SHADERPASS_SHADOWS
            #include "InTerra_HDRP_DefinedGlobalKeywords.hlsl"
            #include "InTerra_TerrainLitTemplate.hlsl"
            #include "InTerra_TerrainLit_Basemap.hlsl"

            ENDHLSL
        }

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

            Cull[_CullMode]

            // To be able to tag stencil with disableSSR information for forward
            Stencil
            {
                WriteMask [_StencilWriteMaskDepth]
                Ref [_StencilRefDepth]
                Comp Always
                Pass Replace
            }

            ZWrite On

            HLSLPROGRAM

            // In deferred, depth only pass don't output anything.
            // In forward it output the normal buffer
            #pragma multi_compile _ WRITE_NORMAL_BUFFER
            #pragma multi_compile_fragment _ WRITE_DECAL_BUFFER
            #pragma multi_compile _ WRITE_MSAA_DEPTH

            #define SHADERPASS SHADERPASS_DEPTH_ONLY
            #include "InTerra_HDRP_DefinedGlobalKeywords.hlsl"
            #include "InTerra_TerrainLitTemplate.hlsl"
            #include "InTerra_TerrainLit_Basemap.hlsl"

            ENDHLSL
        }

        Pass
        {
            Name "Forward"
            Tags{ "LightMode" = "Forward" } // This will be only for transparent object based on the RenderQueue index

            Stencil
            {
                WriteMask [_StencilWriteMask]
                Ref [_StencilRef]
                Comp Always
                Pass Replace
            }

            // In case of forward we want to have depth equal for opaque mesh
            ZTest [_ZTestDepthEqualForOpaque]
            ZWrite [_ZWrite]
            Cull [_CullMode]

            HLSLPROGRAM

            #pragma multi_compile _ DEBUG_DISPLAY
            #pragma multi_compile _ LIGHTMAP_ON
            #pragma multi_compile _ DIRLIGHTMAP_COMBINED
            #pragma multi_compile _ DYNAMICLIGHTMAP_ON
            #pragma multi_compile_fragment _ SHADOWS_SHADOWMASK
            #pragma multi_compile_fragment PROBE_VOLUMES_OFF PROBE_VOLUMES_L1 PROBE_VOLUMES_L2
            #pragma multi_compile_fragment SCREEN_SPACE_SHADOWS_OFF SCREEN_SPACE_SHADOWS_ON
            // Setup DECALS_OFF so the shader stripper can remove variants
            #pragma multi_compile_fragment DECALS_OFF DECALS_3RT DECALS_4RT

            // Supported shadow modes per light type
            #pragma multi_compile_fragment SHADOW_LOW SHADOW_MEDIUM SHADOW_HIGH SHADOW_VERY_HIGH

            #pragma multi_compile USE_FPTL_LIGHTLIST USE_CLUSTERED_LIGHTLIST

            #define SHADERPASS SHADERPASS_FORWARD
            #include "InTerra_HDRP_DefinedGlobalKeywords.hlsl"
            #include "InTerra_TerrainLitTemplate.hlsl"
            #include "InTerra_TerrainLit_Basemap.hlsl"

            ENDHLSL 
        }

        UsePass "Hidden/Nature/Terrain/Utilities/PICKING"
        UsePass "HDRP/TerrainLit/SceneSelectionPass"
    }
    
}