[rescue] "bloated pig X11"
Meelis Roos
mroos at linux.ee
Thu Aug 9 07:49:23 CDT 2012
> You just reminded me of something. With the current talk about replacing X11
> with something better, I was wondering why there doesn't seem to be talk about
> reintroducing something similar to NeWS / Display Postscript. Wayland is
> interesting, but as far as I'm concerned, it's a non-starter as long as they
> keep network transparency out of the spec.
Todays requirements are different because the hardware is vastly
different and usage patterns shift quickly to make use of the new
hardware.
Graphics cards of X11 design era were not safe to use by multiple
applications simultaneously (or no direct access at all) so a mediator
was needed (graphics server), memory access was cheap but CPU and
graphics cards were the bottlenecks. So X server along with some
inter-process communication was a good engineering decision.
Today we have (3D) vector capable graphics cards that emulate the 2D
part using 3D engine, multiple applications can use the card without
lockup or isolation problems. Basically we have a DMA pipeline to the
card, using IRQ-s for flow control. We can mostly take the DMA pipeline
directly to the applications using a thin kernel driver and userspace
library, and do the acceleration stuff in another userspace library. No
need for graphics server because of IPC latency and memory latency of
passing data and control.
Thus the gradual migration to clever clientside libraries that can make
use of vector API-s directly when the time comes.
So DPS would need to be interpreted in the application itself and would
be a userspace API. For a protocol, it might have been OK but as an API
it probably would not be worth much.
Also, current drawing models use vector and transparency (the "PDF"
model), Postscript can use vector well but lacks transparency and has
opaque colors only (can not use the full capabilities of the graphics
cards). Not that transparency is worth much in any static image that you
stare (more strain to the brain to interpret it) but it has its uses to
make some transitions more intuitive.
--
Meelis Roos (mroos at linux.ee)
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