Initializes the library’s graphics routines. It must be called before any other graphics operations.
Closes all of the windows. Until open-graphics is called again, no graphics routines will work.
Determines if the graphics have been opened (or not).
name : string? horiz : exact-nonnegative-integer? vert : exact-nonnegative-integer? (open-viewport name dimensions) → viewport? name : string? dimensions : posn?
Creates a new window called name. The window is horiz pixels wide and vert pixels high. For backward compatibility, a single posn value can be submitted in the place of horiz and vert. The result is a viewport descriptor.
name : string? horiz : exact-nonnegative-integer? vert : exact-nonnegative-integer? (open-pixmap name dimensions) → viewport? name : string? dimensions : posn?
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.
Offscreen pixmaps are also useful in conjunction with viewport->snip (see below). This allows functions to compute with graphical objects and view the graphics when results are returned to the interactions window.
Removes the viewport from the screen and makes subsequent operations dealing with the viewport illegal.
Returns #t if v is a viewport (i.e., a destination for drawing), #f otherwise.