#include "Packages/com.unity.render-pipelines.core/ShaderLibrary/Common.hlsl"
#include "Packages/com.unity.render-pipelines.high-definition/Runtime/ShaderLibrary/ShaderVariables.hlsl"
#include "Packages/com.unity.render-pipelines.high-definition/Runtime/PostProcessing/Shaders/PostProcessDefines.hlsl"
#include "Packages/com.unity.render-pipelines.high-definition/Runtime/PostProcessing/Shaders/DepthOfFieldCommon.hlsl"
#include "Packages/com.unity.render-pipelines.high-definition/Runtime/RenderPipeline/Raytracing/Shaders/RaytracingSampling.hlsl"

#pragma only_renderers d3d11 playstation xboxone xboxseries vulkan metal switch

#pragma kernel KMain

#pragma multi_compile _ ENABLE_ALPHA
#pragma multi_compile _ FORCE_POINT_SAMPLING

#define GROUP_RES  8u
#define GROUP_SIZE (GROUP_RES * GROUP_RES)

CBUFFER_START(cb0)
float4 _Params;
float4 _Params2;
CBUFFER_END

#define NumRings            _Params.x
#define MaxCoCRadius        _Params.y
#define Anamorphism         _Params.z

// Out-of-focus areas, computed at lower res
TEXTURE2D_X(_InputNearTexture);

// Here we write the final output
RW_TEXTURE2D_X(CTYPE, _OutputTexture);

#define ResScale        1.0f
#define OneOverResScale 1.0f
#define MaxColorMip     0.0f
#define AdaptiveSamplingWeights _Params2.xy
#define BlurResolution _Params2.z
#define InvBlurResolution _Params2.w
#include "Packages/com.unity.render-pipelines.high-definition/Runtime/PostProcessing/Shaders/DoFGatherUtils.hlsl"

[numthreads(GROUP_RES, GROUP_RES, 1)]
void KMain(uint3 dispatchThreadId : SV_DispatchThreadID)
{
    UNITY_XR_ASSIGN_VIEW_INDEX(dispatchThreadId.z);

    PositionInputs posInputs = GetPositionInput(float2(dispatchThreadId.xy), _PostProcessScreenSize.zw, uint2(GROUP_RES, GROUP_RES));

    CTYPE output = 0;

    int tileClass = GetTileClass(posInputs.positionSS);

    if (tileClass == SLOW_INFOCUS_TILE)
    {
        SampleData centerSample;
        centerSample.color = GetColorSample(posInputs.positionSS, 0);
        centerSample.CoC = GetCoCRadius(posInputs.positionSS);

        DoFTile tileData;
        LoadTileData(posInputs.positionSS, centerSample, NumRings, tileData);

        float4 outColor;
        float outAlpha;
        DoFGatherRings(posInputs, tileData, centerSample, outColor, outAlpha);
        output.xyz = outColor.xyz;
#ifdef ENABLE_ALPHA
        ComposeAlpha(output, centerSample.color.xyz, outAlpha);
#endif
    }
    else if (tileClass == FAST_DEFOCUS_TILE)
    {
        float2 uv = (posInputs.positionSS + 0.5) * _PostProcessScreenSize.zw;
        uv = ClampAndScaleUV(uv, _PostProcessScreenSize.zw * BlurResolution, 0.5f, _RTHandlePostProcessScale.xy);
        output = SAMPLE_TEXTURE2D_X_LOD(_InputNearTexture, s_linear_clamp_sampler, uv, 0.0).CTYPE_SWIZZLE;
    }
    else
    {
        output = GetColorSample(posInputs.positionSS, 0);
    }

    // Helper function to visualize tile types in case it is needed for debugging
    //DebugTiles(posInputs.positionSS, output.xyz);

    _OutputTexture[COORD_TEXTURE2D_X(posInputs.positionSS)] = (CTYPE)output;
}