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# Basic Commands

- `(open-graphics)`
  Initializes the library's graphics routines. It must be called before any other graphics operations.
- `(close-graphics)`
  Closes all of the windows and until `open-graphics` is called again, no graphics routines will work.
- `(open-viewport name horiz vert)`
  Takes a string name and integers horiz and vert and creates a new window called name. The window is horiz pixels wide and vert pixels high. For backward compatibility, a single `posn` value (see below) can be submitted in the place of horiz and vert. open-viewport returns a viewport descriptor.
- `(open-pixmap name horiz vert)`
  Like `open-viewport`, but the resulting viewport is not displayed on the screen. Offscreen pixmaps are useful for executing a sequence of drawing commands and displaying them all at once with `copy-viewport`.
- `(close-viewport viewport)`
  Takes a viewport descriptor. It removes the viewport from the screen and makes subsequent operations dealing with the viewport illegal.