AW: AW: Creating a planetarium using Ruby

[Unger R. <ric...@te...>]

Hi!

I don't really know, because I have not tried, but I think the problem =
with smooth Animation across 20 Screens in one PC is the bus speed.=20

The PCI bus can transport 127MB / sec.
Lets assume you run each screen at 1024x768, 16 bit =3D 1,5MB / screen
Now 20 Screens is 30MB of data, 127MB/30MB ~ 4, ie you could =
(theoretically) drive the screens at 4 fps.

That's not exactly smooth animation.

Now I freely admit that calculation is simplistic. In a modern computer =
some of the screens would be connected to an AGP bus, some could be =
connected to PCIe. Some boards might include more than one PCI bus, =
meaning the cards don't all have to share the 127MB...

Still, until I actually tried it out, I would be worried about trying to =
move that amount of data (all screens more or less in sync!) on Pc-type =
hardware...

Richard


=20

> -----Urspr=FCngliche Nachricht-----
> Von: Helge Hafting [mailto:hel...@ai...]=20
> Gesendet: Dienstag, 14. M=E4rz 2006 11:35
> An: Unger Richard
> Cc: De Gyves; lin...@li...
> Betreff: Re: AW: Creating a planetarium using Ruby
>=20
> Unger Richard wrote:
>=20
> >Hi!
> >
> >Wow! Now that sounds like a really cool project!
> >
> >I don't think Ruby will necessarily help you here... Ruby is=20
> needed when you want to enable parallel, independant use of=20
> screens, specifically for multiple independent consoles.
> >
> >What you want is more of a giant "Xinerama" setup. However,=20
> IMHO Xinerama may also not be the way to go - it might be=20
> quite some work to recode that layer.
> >
> >Also, 20-30 Video-cards is a lot (last time I checked, I=20
> could put at most 6 in my Workstation ;) )... May I ask if=20
> you have already solved the problem of the hardware you will use?
> > =20
> >
> Well, there is usually no more than 6 or so slots.  Some=20
> multi-PCI server boards may have more, and the multiple buses=20
> will help with the bandwith problem too.
>=20
> Dual screen cards are common.  3- or 4-screen cards are=20
> hideously expensive, but I believe matrox actually have some.=20
>  So it is definitely possible to get to 20 screens in a=20
> single computer, with the right hardware.=20
>=20
> Then there are usb to vga converters.  You can hook up as=20
> many as you like, but such a setup won't be good for quick=20
> animation.  A multiprocessor machine is probably a good idea=20
> when doing animations on 20 screens . . .
>=20
> Helge Hafting
>=20