#include "Packages/com.unity.render-pipelines.core/ShaderLibrary/Common.hlsl"
#include "Packages/com.unity.render-pipelines.core/ShaderLibrary/Color.hlsl"
#include "Packages/com.unity.render-pipelines.high-definition/Runtime/ShaderLibrary/ShaderVariables.hlsl"

#pragma kernel KMain
#pragma kernel KAddMain
#pragma kernel KAccumMain

#pragma only_renderers d3d11 playstation xboxone xboxseries vulkan metal switch switch2

// Input
TEXTURE2D_X(_InputTexture);
TEXTURE2D_X(_InputTexture2);

// Output
RW_TEXTURE2D_X(float4, _OutputTexture);

[numthreads(8, 8, 1)]
void KMain(uint3 dispatchThreadId : SV_DispatchThreadID)
{
    UNITY_XR_ASSIGN_VIEW_INDEX(dispatchThreadId.z);
    uint2 currentPixelCoord = dispatchThreadId.xy;

    float4 exposureMultiplier = 1.0;
    exposureMultiplier.xyz = GetCurrentExposureMultiplier();

    _OutputTexture[COORD_TEXTURE2D_X(currentPixelCoord)] = _InputTexture[COORD_TEXTURE2D_X(currentPixelCoord)] * exposureMultiplier;
}

[numthreads(8, 8, 1)]
void KAddMain(uint3 dispatchThreadId : SV_DispatchThreadID)
{
    UNITY_XR_ASSIGN_VIEW_INDEX(dispatchThreadId.z);
    uint2 currentPixelCoord = dispatchThreadId.xy;

    float4 exposureMultiplier = 1.0;
    exposureMultiplier.xyz = GetCurrentExposureMultiplier();

    float4 accum = _InputTexture[COORD_TEXTURE2D_X(currentPixelCoord)] + _InputTexture2[COORD_TEXTURE2D_X(currentPixelCoord)];
    _OutputTexture[COORD_TEXTURE2D_X(currentPixelCoord)] = accum * exposureMultiplier;
}

[numthreads(8, 8, 1)]
void KAccumMain(uint3 dispatchThreadId : SV_DispatchThreadID)
{
    UNITY_XR_ASSIGN_VIEW_INDEX(dispatchThreadId.z);
    uint2 currentPixelCoord = dispatchThreadId.xy;

    float4 exposureMultiplier = 1.0;
    exposureMultiplier.xyz = GetCurrentExposureMultiplier();

    float4 accum = _OutputTexture[COORD_TEXTURE2D_X(currentPixelCoord)] + _InputTexture[COORD_TEXTURE2D_X(currentPixelCoord)] * exposureMultiplier;
    _OutputTexture[COORD_TEXTURE2D_X(currentPixelCoord)] = accum;
}