Granted, about the NlogN and cache misses penalties.. but whateve solution you choose will be at a cost. Double rendering cloud layers? There goes your fill rate out the window! If anyone is interested in experimenting, I'll be happy to provide the code that you can toggle alpha sorting. Ive never done a performace comparison, but seeing as you guys have something implemented that can excersise it, it might be worth your while to assess its merits quantitavely.
By the way, do you mind elaborating on what you mean by "use of destination alpha". regards, Themie -----Original Message----- From: Andy Ross [mailto:[EMAIL PROTECTED]] Sent: Thursday, 18 July 2002 2:22 AM To: [EMAIL PROTECTED] Subject: Re: [Flightgear-devel] ANN: a new dimension to FlightGear Gouthas, Themie wrote: > I dont think the alpha sorting code was ever comitted, so currently > I dont beleive PLIB will alpha sort. I'm not sure this is a great idea in any case. There are a *lot* of these objects, and doing an NlogN sort of them (with attendant geometry processing to get the distances, not to mention the cache effects of doing an extra sweep over all of them) every frame is likely to be awfully slow. Hacking around the issue by diddling the rendering order (and maybe double-rendering problem objects like nearby clouds) sounds like the best idea to me. We could also investigate the use of destination alpha, which is available and fast on high end hardware these days. Andy -- Andrew J. Ross NextBus Information Systems Senior Software Engineer Emeryville, CA [EMAIL PROTECTED] http://www.nextbus.com "Men go crazy in conflagrations. They only get better one by one." - Sting (misquoted) _______________________________________________ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel _______________________________________________ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
