1 Basic Commands
(open-graphics) → void?
Initializes the library’s graphics routines. It must be called before any other graphics operations.
(close-graphics) → void?
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).
(open-viewport name horiz vert) → viewport?
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.
(open-pixmap name horiz vert) → viewport?
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.
(close-viewport viewport) → void?
viewport : viewport?
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.