&gt; <i>After a further six months of nagging doubts about the proprietary “window mask” technology I had designed, I decided to take the plunge and do what Jörn had suggested might lead to a considerable increase in rendering speed: namely, to abandon the window masks (which, it turned out, might as well have been called “regions”), and use a traditional dirty-rectangle window management system, as used in SymbOS.</i><p>This is pretty funny when you recall regions were a key part of the original Macintosh system software — as described in “I Still Remember Regions”:<p><a href="http:&#x2F;&#x2F;www.folklore.org&#x2F;StoryView.py?story=I_Still_Remember_Regions.txt" rel="nofollow">http:&#x2F;&#x2F;www.folklore.org&#x2F;StoryView.py?story=I_Still_Remember_...</a><p>See also “Busy Being Born”, currently on the front page:<p><a href="http:&#x2F;&#x2F;www.folklore.org&#x2F;StoryView.py?story=Busy_Being_Born.txt" rel="nofollow">http:&#x2F;&#x2F;www.folklore.org&#x2F;StoryView.py?story=Busy_Being_Born.t...</a><p><a href="https:&#x2F;&#x2F;news.ycombinator.com&#x2F;item?id=10188952" rel="nofollow">https:&#x2F;&#x2F;news.ycombinator.com&#x2F;item?id=10188952</a>