I was looking at how Morphic did drawing a week back and noticed  
something odd.
If you bring up Tetris and start a game, then cover the tetris board  
with some other mophic object
why the Tetris player objects are updated even if they are invisible  
(completely hidden). In this
case Morphic redraws the foreground object.

Although there is no visual indication of this, I'd expect the resource  
consumption for doing the
drawing in time & cpu time isn't minimal. Or is it smaller than the  
time needed to figure out if a redraw
should happen?

Thus someone might want to look at why completely hidden objects get  
redrawn.

PS Apple has a nice tool to expose window drawing activity in the  
Quartz layer which exposed this issue.

--
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John M. McIntosh <johnmci at smalltalkconsulting.com> 1-800-477-2659
Corporate Smalltalk Consulting Ltd.  http://www.smalltalkconsulting.com
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