[comp.windows.x] graphics in a viewport

rws@EXPO.LCS.MIT.EDU (Bob Scheifler) (11/16/88)

	If you do graphics in the viewport 
	and then scroll around, you lose the graphics that have
	been done. You also can't do graphics off of the displayed 
	viewport (almost a necessity).

If you want the graphics to be retained, you need to enable backing-store
for the widget (and any inferiors, sorry) that you place inside the viewport
that you want the graphics retained for.  Alternatively, you can try
enabling save-unders on just the viewport window, but some implementations of
save-unders may discard graphics to save-undered regions.

You also need to have a server (like those in R3) that support backing-store
or save-unders.