function createWindow(wnd, rebuild)
    if wnd.element then
        if rebuild then
            destroyElement(wnd.element)
        else
            guiSetVisible(wnd.element, true)
            guiBringToFront(wnd.element)
            g_openedWindows[wnd] = true
            if wnd.oncreate then
                wnd.oncreate()
            end
            return
        end
    end
    
    _planWindow(wnd)
    _buildWindow(wnd)
end