(WindowImp::poll) : Update the canvas before processing events (WindowImp::poll, WindowImp::render) : Use the Box::NEED_REPAINT flag to minimize the number of the canvas repaints
(WindowImp::poll) : Update the canvas before processing events
(WindowImp::poll, WindowImp::render) : Use the Box::NEED_REPAINT flag to minimize the number of the canvas repaints

mattl/es-operating-system,mattl/es-operating-system,mattl/es-operating-system,mattl/es-operating-system,mattl/es-operating-system,mattl/es-operating-system,mattl/es-operating-system