Method selectBestVisual

src/SFML/Window/Unix/GlxContext.cpp:294–387

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XVisualInfo GlxContext::selectBestVisual(::Display* display, unsigned int bitsPerPixel, const ContextSettings& settings)
{
    // Make sure that extensions are initialized
    ensureExtensionsInit(display, DefaultScreen(display));

    const int screen = DefaultScreen(display);

    // Retrieve all the visuals
    int count = 0;
    // NOLINTNEXTLINE(cppcoreguidelines-avoid-c-arrays,modernize-avoid-c-arrays)
    if (const auto visuals = X11Ptr<XVisualInfo[]>(XGetVisualInfo(display, 0, nullptr, &count)))
    {
        // Evaluate all the returned visuals, and pick the best one
        int         bestScore  = 0x7FFFFFFF;
        XVisualInfo bestVisual = XVisualInfo();
        for (std::size_t i = 0; i < static_cast<std::size_t>(count); ++i)
        {
            // Filter by screen
            if (visuals[i].screen != screen)
                continue;

            // Check mandatory attributes
            int doubleBuffer = 0;
            glXGetConfig(display, &visuals[i], GLX_DOUBLEBUFFER, &doubleBuffer);
            if (!doubleBuffer)
                continue;

            // Extract the components of the current visual
            int red           = 0;
            int green         = 0;
            int blue          = 0;
            int alpha         = 0;
            int depth         = 0;
            int stencil       = 0;
            int multiSampling = 0;
            int samples       = 0;
            int sRgb          = 0;
            glXGetConfig(display, &visuals[i], GLX_RED_SIZE, &red);
            glXGetConfig(display, &visuals[i], GLX_GREEN_SIZE, &green);
            glXGetConfig(display, &visuals[i], GLX_BLUE_SIZE, &blue);
            glXGetConfig(display, &visuals[i], GLX_ALPHA_SIZE, &alpha);
            glXGetConfig(display, &visuals[i], GLX_DEPTH_SIZE, &depth);
            glXGetConfig(display, &visuals[i], GLX_STENCIL_SIZE, &stencil);

            if (SF_GLAD_GLX_ARB_multisample)
            {
                glXGetConfig(display, &visuals[i], GLX_SAMPLE_BUFFERS_ARB, &multiSampling);
                glXGetConfig(display, &visuals[i], GLX_SAMPLES_ARB, &samples);
            }
            else
            {
                multiSampling = 0;
                samples       = 0;
            }

            if (SF_GLAD_GLX_EXT_framebuffer_sRGB || SF_GLAD_GLX_ARB_framebuffer_sRGB)
            {
                glXGetConfig(display, &visuals[i], GLX_FRAMEBUFFER_SRGB_CAPABLE_ARB, &sRgb);