Function CompressDXT5

engine/Poseidon/Graphics/Textures/DXTCompressor.cpp:956–976

}

std::vector<uint8_t> CompressDXT5(const uint8_t* rgba, int width, int height)
{
    size_t sz = CompressedSize(width, height, false);
    std::vector<uint8_t> out(sz);
    int bw = (width + 3) / 4;
    int bh = (height + 3) / 4;
    auto* dst = reinterpret_cast<DXTBlock128*>(out.data());

    for (int by = 0; by < bh; ++by)
    {
        for (int bx = 0; bx < bw; ++bx)
        {
            DWORD pixels[16];
            extractBlockARGB(rgba, width, height, bx, by, pixels);
            CompressDXT1Block(dst->color, pixels, true);
            CompressDXTABlock(dst->alphaImp, pixels);
            dst++;
        }
    }
    return out;
}

} // namespace DXTCompressor