[sldev] [VIEWER] OpenGL clipping in the GUI

Lawson English lenglish5 at cox.net
Sun Sep 9 06:37:21 PDT 2007


I'm trying to devise a simple floater interface for my next project 
(keyword floater for LSL) and I noticed that clipping for the GUI 
appears to be a cooperative affair, rather than enforced by the view 
hierarchy of a given floater. Is this because OpenGL's clipping routines 
are slow/inappropriate for GUI development without a lot of work, or 
merely a legacy of SL's haphazard development history?

I'm asking because I'm used to a GUI framework enforcing a bit of 
discipline on what is drawn on the screen where and it is disconcerting 
to see buttons moving in all directions at random on the screen outside 
the parent window if you get a flag or xml parameter wrong.

In the long run, if possible, I think that the GUI needs to be revised 
from top to bottom in order to enforce a traditional GUI view hierarchy, 
including inherited clipping rectangles and even regions. I can see no 
reason why we can't have round windows if we want them for some purpose. 
Certainly, if the client-world interface converges the way I think it 
could (and probably should), I can foresee plenty of situations where 
the interface should be more organic in appearance which would require 
"windows" that have no set-in-stone shape, and a clip-view-hierarchy 
would be far more important in such a situation.


More information about the SLDev mailing list