On Thu, Apr 28, 2005 at 11:45:57 +0200, Jens M
Andreasen wrote:
Hi all!
The other day I dressed up my application with a fancy g5-ish pixmap
theme. Looks good and expensive :)
As it turned out, it really was expensive (counting cpu-clocks.)
Unless you have an ultra-bleeding edge X setup a lot of the work of the
pixmap drawing is done by the CPU, thats quite a lot of maths. There is
some new tech which uses OpenGL to do the X drawing, which moves a lot of
the load off to the graphics card, but its not really available yet.
http://freedesktop.org/wiki/Software_2fXgl
This /really/ helps, for e.g. I have a beta version of meterbridge that
can use OpenGL or SDL (X) pixmaps, on my thinkpad (which has a comparitivly
hardcore graphics chip, but its only a laptop) I can fill the screen with
32 scaled VU meters at about 3% CPU load, with SDL it maxes out the CPU
when I have about half that number of unscaled meters (the SDL code doesnt
do scaling, its too expensive).
Still leaves me wondering how on earth gtk can use the equivalence of a
200 Mhz pentium to figure out that nothing happened?
So a faster redraw is of course always welcome, but redrawing (or
whatever is going on) when old == new is really not on my todo list.
What is even "funnier" is that mouse behaviour seems to take a different
route with next to no overhead.