Re: Sprites

["Andreas C. Lemke" <andreas@BOULDER.COLORADO.EDU>]

>  I'd like to know how to do the second (delete) without doing the first (erase).

Use the following undocumented message:

|   (send <your-dynamic-window>
|         :delete-displayed-presentation <your-presentation>)

There is also another very useful undocumented message.  It does what
erase-displayed-presentation does, but then redraws everything
underneath the erased presentation.

| (defmethod (:erase-displayed-presentation dynamic-window)
| 	      (presentation
| 	          &key (redisplay-overlapping-presentations t)
| 		        (delete-too t) (clear-inferiors t)
| 				     (enable-recording t))

The next one is sort of the opposite of :erase-d-p.  It adds the
presentation to the presentation history and then, if you say
":redisplay-overlapping-presentations t", redraws it and everything
inside the box of the presentation.

| (defmethod (:unerase-displayed-presentation dynamic-window)
| 	      (presentation &key redisplay-overlapping-presentations)

These functions are used in the Concordia graphics editor.

..................					 Andreas C. Lemke
... andreas ..:-).				    CS Dept., Univ. of Colorado
..................				     andreas@sigi.colorado.edu