@Override
    public boolean mouseClicked(double x, double y, int glfwMouseButton) {
        lastClickTime = System.currentTimeMillis();
        boolean consumed = super.mouseClicked(x, y, glfwMouseButton);
        return operateOnZOrderedSubtree(new Point((int) x, (int) y), (n, p, c) -> n.mouseClicked(p, glfwMouseButton, c), consumed);
    }
Base Screen class that implements the UI Node system. This is for UIs that do not have containers.
core/src/main/java/mrtjp/projectred/redui/RedUIScreen.java