BlitCookie.compute

#pragma only_renderers d3d11 vulkan metal glcore
#define GROUP_SIZE_X 8
#define GROUP_SIZE_Y 8


Texture2D<float4>	g_Source;
RWTexture2D<float4> g_Destination;

SamplerState sampler_g_Source;

uint g_TextureWidth;
uint g_TextureHeight;

// Projects (blits) a face of a cubemap on a 2D texture 
#pragma kernel BlitGrayScaleCookie
[numthreads(GROUP_SIZE_X, GROUP_SIZE_Y, 1)]
void BlitGrayScaleCookie(in uint2 gidx : SV_DispatchThreadID)
{
    if (gidx.x >= g_TextureWidth || gidx.y >= g_TextureHeight)
        return;

    
    float2 texCoord = float2((gidx.x + 0.5f) / g_TextureWidth, (gidx.y + 0.5f) / g_TextureHeight);

    float c = g_Source.SampleLevel(sampler_g_Source, texCoord, 0).w;
    g_Destination[gidx] = float4(c, c, c, 1);
}