Function OptimizeBlockCompression

tools/cli/GraphicsPasses.cpp:778–965

    return true;
}

bool OptimizeBlockCompression(
    ntc::IContext* context,
    ntc::ITextureSetMetadata* textureSetMetadata,
    nvrhi::IDevice* device,
    nvrhi::ICommandList* commandList,
    float psnrThreshold,
    GraphicsResourcesForTextureSet const& graphicsResources)
{
    assert(device);
    
    bool anyBC7Textures = false;
    for (int textureIndex = 0; textureIndex < textureSetMetadata->GetTextureCount(); ++textureIndex)
    {
        ntc::ITextureMetadata* textureMetadata = textureSetMetadata->GetTexture(textureIndex);
        if (textureMetadata->GetBlockCompressedFormat() == ntc::BlockCompressedFormat::BC7)
        {
            anyBC7Textures = true;
            break;
        }
    }

    if (!anyBC7Textures)
        return true;

    GraphicsBlockCompressionPass blockCompressionPass(device, 1);
    if (!blockCompressionPass.Init())
        return false;

    GraphicsImageDifferencePass compareImagesPass(device);
    if (!compareImagesPass.Init())
        return false;
    
    ntc::TextureSetDesc const& textureSetDesc = textureSetMetadata->GetDesc();

    nvrhi::BufferHandle modeBuffer;
    std::vector<uint8_t> blockCompressedData;

    for (int textureIndex = 0; textureIndex < textureSetMetadata->GetTextureCount(); ++textureIndex)
    {
        ntc::ITextureMetadata* textureMetadata = textureSetMetadata->GetTexture(textureIndex);
        if (textureMetadata->GetBlockCompressedFormat() != ntc::BlockCompressedFormat::BC7)
            continue;

        GraphicsResourcesForTexture const& textureResources = graphicsResources.perTexture[textureIndex];

        for (int mipLevel = 0; mipLevel < textureSetDesc.mips; ++mipLevel)
        {
            int mipWidth = std::max(textureSetDesc.width >> mipLevel, 1);
            int mipHeight = std::max(textureSetDesc.height >> mipLevel, 1);
            int mipWidthInBlocks = (mipWidth + 3) / 4;
            int mipHeightInBlocks = (mipHeight + 3) / 4;

            // First pass - compress without the mode buffer, doing an exhaustive mode search for each block

            ntc::MakeBlockCompressionComputePassParameters compressionParams;
            compressionParams.srcRect.width = mipWidth;