Method initWithATITCData

core/platform/Image.cpp:2349–2485

}

bool Image::initWithATITCData(uint8_t* data, ssize_t dataLen, bool ownData)
{
    /* load the .ktx file */
    KTXv1Header* header = (KTXv1Header*)data;
    _width              = header->pixelWidth;
    _height             = header->pixelHeight;
    _numberOfMipmaps    = header->numberOfMipmapLevels;

    int blockSize = 0;
    switch (header->glInternalFormat)
    {
    case KTXv1Header::InternalFormat::ATC_RGB_AMD:
        blockSize = 8;
        break;
    case KTXv1Header::InternalFormat::ATC_RGBA_EXPLICIT_ALPHA_AMD:
        blockSize = 16;
        break;
    case KTXv1Header::InternalFormat::ATC_RGBA_INTERPOLATED_ALPHA_AMD:
        blockSize = 16;
        break;
    default:
        break;
    }

    /* pixelData point to the compressed data address */
    int pixelOffset    = KTX_V1_HEADER_SIZE + header->bytesOfKeyValueData + 4;
    uint8_t* pixelData = (uint8_t*)data + pixelOffset;

    /* calculate the dataLen */
    int width  = _width;
    int height = _height;

    bool hardware = Configuration::getInstance()->supportsATITC();
    if (hardware)  // compressed data length
    {
        AXLOGD("this is atitc H decode");

        switch (header->glInternalFormat)
        {
        case KTXv1Header::InternalFormat::ATC_RGB_AMD:
            _pixelFormat = backend::PixelFormat::ATC_RGB;
            break;
        case KTXv1Header::InternalFormat::ATC_RGBA_EXPLICIT_ALPHA_AMD:
            _pixelFormat = backend::PixelFormat::ATC_EXPLICIT_ALPHA;
            break;
        case KTXv1Header::InternalFormat::ATC_RGBA_INTERPOLATED_ALPHA_AMD:
            _pixelFormat = backend::PixelFormat::ATC_INTERPOLATED_ALPHA;
            break;
        default:
            break;
        }
    }
    else  // decompressed data length
    {     /* if it is not gles or device do not support ATITC, decode texture by software */

        AXLOGW("Hardware ATITC decoder not present. Using software decoder");

        _pixelFormat = backend::PixelFormat::RGBA8;