On Sat, 5 Feb 2005 20:25:42 -0600, Kent Rosenkoetter <[EMAIL PROTECTED]> wrote: > On Sat, 5 Feb 2005 02:53:58 -0500, Daniel Phillips <[EMAIL PROTECTED]> wrote: > > On Friday 04 February 2005 17:46, John Tsiombikas (Nuclear / the Lab) > > wrote: > > > > Decent engines do very little overdraw. Hidden geometry is removed > > > > before it ever gets to the card. In ID games, only movable objects > > > > are dumped into the Z buffer on top of the scenery, which is only > > > > one pixel deep. ID puts a huge load on the graphics card, but it's > > > > not overdraw, it's things multitexturing and more recently, > > > > shaders. I don't know too many details about the Unreal engine, > > > > but I'm fairly confident they don't just dump all their geometry > > > > onto the card either. > > > > > > Not everything is quake though (and it's derivatives). Techniques to > > > avoid overdraw in 1st person shooters and similar *static* *close > > > space* environments have been developed to a great extend, but there > > > are a lot of applications out there that do totally different things, > > > and most of the time avoiding overdraw is not feasible. Especially in > > > programs with highly dynamic 3D environments. > > > > If you're talking about engineering and real time modelling, those are > > not twitch games and don't have to keep up a steady 30-60 frames per > > second. > > > > I don't belittle the importance of non-game 3D graphics applications, > > however I use games to measure performance because everybody else does. > > If it handles games well, it's going to handle a lot of things well. > > This card will not have the raw power to do gaming of the type you > mention. And it will not be doing the really massive CAD renderings > either. But if you want to talk about demanding 30-60 frames per > second with no lag and frustrating amounts of overdraw, all you have > to do is look at the /primary purpose/ of the card: compositing > numerous overlapping windows. That is pretty much entirely overdraw, > and it unquestionably demands unflinching framerate. Any dip will be > perceived by the user as slow and incompetent graphics. This is going > to be our test, the one we cannot fail.
Excellent point. So, if you need to composite 100 windows, each of which is 50% the size of the screen, what is your required pixel rate? _______________________________________________ Open-graphics mailing list [email protected] http://lists.duskglow.com/mailman/listinfo/open-graphics List service provided by Duskglow Consulting, LLC (www.duskglow.com)
