How many times? was: Compression design

[Bart Coppens]

On Monday 27 November 2006 20:41, Boudewijn Rempt wrote:
> I'm already considering another approach, piggy-backing off the list of
> swappable tiles, but there's this: on creating an image, the histogram
> widget indecently often iterates over the paint device:
Yes, I admit to that indecency. But by doing that, I could postpone doing the 
histogram until after the user has finished painting (or a filter has done 
its job), so as to not bother the user while with decreased performance while 
painting. Especially when a filter needs to do stuff to the entire 
paintdevice in more than one pass, it's better to do the histogram at the 
end.
Now I could've done more evil tricks like do triggers on swapout, or store the 
stuff alongside a tile, but I think that'd expose the tiles too much. Of 
course, I'm open to suggestions here.

Bart