Method newImage

core/2d/RenderTexture.cpp:528–574

get buffer as Image */

/* get buffer as Image */
void RenderTexture::newImage(std::function<void(RefPtr<Image>)> imageCallback, bool eglCacheHint)
{
    AXASSERT(_pixelFormat == backend::PixelFormat::RGBA8, "only RGBA8888 can be saved as image");

    if ((nullptr == _texture2D))
    {
        return;
    }

    const Vec2& s = _texture2D->getContentSizeInPixels();

    // to get the image size to save
    //        if the saving image domain exceeds the buffer texture domain,
    //        it should be cut
    int savedBufferWidth       = (int)s.width;
    int savedBufferHeight      = (int)s.height;
    bool hasPremultipliedAlpha = _texture2D->hasPremultipliedAlpha();

    auto callback = [hasPremultipliedAlpha, imageCallback](const backend::PixelBufferDescriptor& pbd) {
        if (pbd)
        {
            auto image = utils::makeInstance<Image>(&Image::initWithRawData, pbd._data.getBytes(), pbd._data.getSize(),
                                                    pbd._width, pbd._height, 8, hasPremultipliedAlpha);
            imageCallback(image);
        }
        else
            imageCallback(nullptr);
    };
#if defined(AX_USE_GL)
    if (eglCacheHint)
    {
        auto colorAttachment = _renderTarget->_color[0].texture;
        if (colorAttachment)
        {
            backend::PixelBufferDescriptor pbd;
            static_cast<backend::CommandBufferGL*>(_director->getRenderer()->getCommandBuffer())
                ->readPixels(_renderTarget, 0, 0, colorAttachment->getWidth(), colorAttachment->getHeight(),
                             colorAttachment->getWidth() * 4, true, pbd);
            callback(pbd);
        }
    }
    else
        _director->getRenderer()->readPixels(_renderTarget, callback);
#else
    _director->getRenderer()->readPixels(_renderTarget, callback);
#endif
}

void RenderTexture::draw(Renderer* renderer, const Mat4& transform, uint32_t flags)
{