Method initWithS3TCData

core/platform/Image.cpp:2222–2347

}

bool Image::initWithS3TCData(uint8_t* data, ssize_t dataLen, bool ownData)
{
    const uint32_t FOURCC_DXT1 = makeFourCC('D', 'X', 'T', '1');
    const uint32_t FOURCC_DXT3 = makeFourCC('D', 'X', 'T', '3');
    const uint32_t FOURCC_DXT5 = makeFourCC('D', 'X', 'T', '5');

    /* load the .dds file */

    S3TCTexHeader* header = (S3TCTexHeader*)data;
    _width                = header->ddsd.width;
    _height               = header->ddsd.height;
    _numberOfMipmaps      = MAX(
        1,
        header->ddsd.DUMMYUNIONNAMEN2
            .mipMapCount);  // if dds header reports 0 mipmaps, set to 1 to force correct software decoding (if needed).
    _dataLen      = 0;
    int blockSize = (FOURCC_DXT1 == header->ddsd.DUMMYUNIONNAMEN4.ddpfPixelFormat.fourCC) ? 8 : 16;

    /* calculate the dataLen */

    int width  = _width;
    int height = _height;

    const int pixelOffset = sizeof(S3TCTexHeader);
    uint8_t* pixelData    = data + pixelOffset;

    bool hardware = Configuration::getInstance()->supportsS3TC();
    /* if hardware supports s3tc, set pixelformat before loading mipmaps, to support non-mipmapped textures  */
    if (hardware)
    {  // decode texture through hardware

        if (FOURCC_DXT1 == header->ddsd.DUMMYUNIONNAMEN4.ddpfPixelFormat.fourCC)
        {
            _pixelFormat = backend::PixelFormat::S3TC_DXT1;
        }
        else if (FOURCC_DXT3 == header->ddsd.DUMMYUNIONNAMEN4.ddpfPixelFormat.fourCC)
        {
            _pixelFormat = backend::PixelFormat::S3TC_DXT3;
        }
        else if (FOURCC_DXT5 == header->ddsd.DUMMYUNIONNAMEN4.ddpfPixelFormat.fourCC)
        {
            _pixelFormat = backend::PixelFormat::S3TC_DXT5;
        }
    }
    else
    {  // will software decode
        _pixelFormat = backend::PixelFormat::RGBA8;

        // prepare data for software decompress
        for (int i = 0; i < _numberOfMipmaps && (width || height); ++i)
        {
            if (width == 0)
                width = 1;
            if (height == 0)
                height = 1;

            _dataLen += (height * width * 4);