Linked by Eugenia Loli on Tue 11th Nov 2003 21:43 UTC, submitted by John
X11, Window Managers The new X Server developed under the sponsorship of is aiming at replacing XFree86. Some code will be re-used but the core will be rewritten by Keith Packard and others. The new X server features full support for transparency, and has window-level image compositing among other things. Check out the screenshots (one more added, now there are four shots).
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by Rayiner Hashem on Wed 12th Nov 2003 05:17 UTC

First, please read the paper. You don't seem to have a good understanding of how these new extensions work:

Interestingly, this hack will likely be a speed-killer... and X11's existing throughput issues would make it a huge disappointment.
1) Toolkits do not double buffer the way you think they do. The back-buffer is only allocated temporarily while the widget is being redrawn. Thus, the memory usage is very small --- only the size of one widget at any given point.

2) Its just an extra blit. Blits are really, really, fast these days. With 6.4GB/sec of memory bandwidth on top in my lowly GeForce4 MX, blit-speed is not a bottleneck.

3) X11 doesn't have throughput issues. Its throughput is really fast, as several benchmarks have shown. X11 apps have latency issues in places, and these extensions alleviate a lot of those.

Even then, you'll still need a 1Ghz+ processor because X11's added overhead still causes a lot of grief when drawing buffered graphics
X11 was designed for 20MHz processors. You can do double-buffered graphics on X11 by rendering directly to a pixmap and blitting using ShmPutImage. That's pretty much what you have to do with DirectX as well. What overhead are you talking about? Have you ever even done graphics programming?

(you could use the XDGA extension, but it only works for full screen games and not the X desktop, so that's out).
Didn't you get the memo? Direct graphics access is passe. DGA is depricated, and nobody seems eager to replace it.

Only OS X and Athene (which already works on X11) have got it right so far - something like this really needs to be done correctly from scratch, not just hacked on to an antiquated display system.
With the current model, apps will just have to be updated. Simply don't bother double-buffering, and you're done. If you start from scratch, you'll have to rewrite your apps!