Re: expose event compression

[Paul Davis <paul linuxaudiosystems com>]

>Hi all, 
>
>I'm porting an app to gtk2 and I've come across some performance problems caused (I think) by
> gtk's new expose event compression system.
>
>One of the app's widgets is an image display window, and one of the tools is a panner. Pure l
>eft/right and up/down pans are fast and smooth, but diagonal drags are very choppy. I think t
>his is because gtk is sending me the bounding box of all exposes since the last repaint, and 
>for a diagonal drag, the bounding box of a thin strip down the right and a thin strip across 
>the bottom is the entire window. 
>
>Has anyone come across this before, and is there an easy solution?

there's a flag in the expose event structure that indicates that there
are more expose events pending. its often a nice optimization to delay
updates until the "last" expose event. sometimes, though, it can lead
to the wrong thing.