Class WindowGlfw

imgui-app/src/main/java/imgui/app/WindowGlfw.java:52–227

GLFW + OpenGL 3 implementation of Window. Mirrors the historical (pre-SDL) behavior of Window: GLFW window creation with GL 3.0 / 3.2 context, GL clear, GLFW poll/swap, and multi-viewport handling via ImGuiConfigFlags#ViewportsEnable.

 * and multi-viewport handling via {@link ImGuiConfigFlags#ViewportsEnable}.
 */
public class WindowGlfw extends Window {
    private final ImGuiImplGlfw imGuiGlfw = new ImGuiImplGlfw();
    private final ImGuiImplGl3 imGuiGl3 = new ImGuiImplGl3();

    private String glslVersion = null;

    /**
     * Pointer to the native GLFW window.
     */
    private long handle;

    @Override
    protected void init(final Configuration config) {
        initWindow(config);
        owner.initImGui(config);
        imGuiGlfw.init(handle, true);
        imGuiGl3.init(glslVersion);
    }

    @Override
    protected void dispose() {
        imGuiGl3.shutdown();
        imGuiGlfw.shutdown();
        owner.disposeImGui();
        disposeWindow();
    }

    /**
     * Method to create and initialize GLFW window.
     *
     * @param config configuration object with basic window information
     */
    protected void initWindow(final Configuration config) {
        GLFWErrorCallback.createPrint(System.err).set();

        if (!glfwInit()) {
            throw new IllegalStateException("Unable to initialize GLFW");
        }

        decideGlGlslVersions();

        glfwWindowHint(GLFW_VISIBLE, GLFW_FALSE);
        handle = glfwCreateWindow(config.getWidth(), config.getHeight(), config.getTitle(), MemoryUtil.NULL, MemoryUtil.NULL);

        if (handle == MemoryUtil.NULL) {
            throw new RuntimeException("Failed to create the GLFW window");
        }

        try (MemoryStack stack = MemoryStack.stackPush()) {
            final IntBuffer pWidth = stack.mallocInt(1); // int*
            final IntBuffer pHeight = stack.mallocInt(1); // int*

            glfwGetWindowSize(handle, pWidth, pHeight);
            final GLFWVidMode vidmode = Objects.requireNonNull(glfwGetVideoMode(glfwGetPrimaryMonitor()));
            glfwSetWindowPos(handle, (vidmode.width() - pWidth.get(0)) / 2, (vidmode.height() - pHeight.get(0)) / 2);
        }

        glfwMakeContextCurrent(handle);