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.