Function updateFullscreenResolutions

src/OpenLoco/src/Ui.cpp:714–770

    }

    void updateFullscreenResolutions()
    {
        // Query number of display modes
        int32_t displayIndex = SDL_GetDisplayForWindow(_window);

        // Get desktop aspect ratio
        const SDL_DisplayMode* desktopMode = SDL_GetDesktopDisplayMode(displayIndex);
        float desktopAspectRatio = (float)desktopMode->w / desktopMode->h;

        // Get resolutions
        int32_t numDisplayModes{};
        SDL_DisplayMode** displayModes = SDL_GetFullscreenDisplayModes(displayIndex, &numDisplayModes);
        if (!displayModes || numDisplayModes <= 0)
        {
            Logging::error("SDL_GetFullscreenDisplayModes failed: {}", SDL_GetError());
            return;
        }

        auto resolutions = std::vector<Resolution>();
        for (int32_t i = 0; i < numDisplayModes; i++)
        {
            const auto* mode = displayModes[i];
            if (mode->w > 0 && mode->h > 0)
            {
                float aspectRatio = (float)mode->w / mode->h;
                if (_resolutionsAllowAnyAspectRatio || std::fabs(desktopAspectRatio - aspectRatio) < 0.0001f)
                {
                    resolutions.push_back({ mode->w, mode->h });
                }
            }
        }

        SDL_free(displayModes);

        // Sort by area
        std::sort(resolutions.begin(), resolutions.end(), [](const Resolution& a, const Resolution& b) -> bool {
            int32_t areaA = a.width * a.height;
            int32_t areaB = b.width * b.height;
            return areaA < areaB;
        });

        // Remove duplicates
        auto last = std::unique(resolutions.begin(), resolutions.end(), [](const Resolution& a, const Resolution& b) -> bool {
            return (a.width == b.width && a.height == b.height);
        });
        resolutions.erase(last, resolutions.end());

        // Update configured fullscreen resolution if not set
        auto& cfg = Config::get().display.fullscreenResolution;
        if (!cfg.isPositive())
        {
            cfg.width = resolutions.back().width;
            cfg.height = resolutions.back().height;
        }

        _fsResolutions = resolutions;
    }