[Xorg] PEX and XIE
eich at pdx.freedesktop.org
Sun Feb 29 13:13:34 PST 2004
Roland Mainz writes:
> Egbert Eich wrote:
> > > Mozilla's Xlib toolkit has support for XIE... and maybe the (default)
> > > GTK+ toolkit for Mozilla get it's XIE support back since this gives a
> > > huge speedup for image scaling/blending on platforms who still have XIE
> > > support available by default (I am looking here at Solaris/Xsun :) ...
> > > PEX can (IMO) be removed... but if you remove XIE it would be nice to
> > > provide an alternative which supports things like image scaling,
> > > rotation and blending (RENDER doesn't count - it's broken by design...
> > > ;-/).
> > If it really gives a signifficant speedup this issue
> > should be reinvestigated. I once was told it was slow.
> XIE makes image scaling faster in Mozilla's case since FAR LESS data are
> transferred over the wire. Think about a small 400x300 image scaled up
> to 800x600. In the case of client-side scaling four times more image
> bytes are transferred over the wire than pushing the image as-is to the
> server and let the server scale it.
That's true for a small image of this size. However what about
Images that are far bigger than the available screen size?
You'd only want to transfer a protion of them.
I admit that this is a corner case, but since somebody once
bragged to me how much better a Windows image viewer can handle
this situation than the X client this person has tried it
may become an issue that still needs to be handled on the
> In the case of alpha blending a whole round-trip is saved - and again
> all the image bytes transferred from server to client (XGetImage()) and
> back (XPutIMage()) ...
> > That it is faster on Solaris may be as SUN has enhanced it.
> I am not sure whether Sun touched the XIE sources for their
> implementation... I simply guess the issue explained above is enougth to
> explain the performace enhancement.
Well, maybe not. It was something I've heared.
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