A Renderer is a member of the Game View system and is responsible for
drawing a Window widget to the screen. Only one renderer exists per
application. It implements the Process interface to draw on a tick when
the specified framerate allows. The renderer uses double-buffering for
updating frames.
Create a Renderer object that draws 'win' to the screen at a maximum
frequency of 'fps'. For best performance, do not attach the Renderer to
a Process_Manager running at a frequency less than 'fps'; it's best if
the Process is ticked at the same frequency, or a multiple of it.