On Tuesday 03 January 2006 22:04, Ben Clark wrote: > Hey There > > Although i have a fairly moderate spec machine i've noticed that FG frame > rate can be extremely low, particually when near the carrier, or when > playing multiplayer. Many people have told me this is due to the sever > complexity of the models.
With regards to the models the real culprit is the textures more than the poly count. Yes, the poly count on the models does affect the performance but nowhere near as much as when the textures can't fit inside VRAM and have to be swapped across the PCI/AGP/PCI-E bus every frame. Textures that use transparency effect are also pretty costly. With regards to MP aircraft : We need the default aircraft to have a decent pyramid of LOD models as well texture pyramids. There's no point in loading high resolution textures for MP aircraft that are barely within visual range. Someone correct me if I'm wrong but from what I understand even with mipmapping the main texture still has to be loaded into VRAM. All that happens is that a lower res mipmap is used if the model is further away. So instead of loading large textures why not load a lower resolution one and build mip maps of that one instead. We can either make all the FG aircraft comply or we need to make some sort of separate MP aircraft package like MSFS guys do (example Project AI). > My question is, does anyone know the most severe bottlenecks in the FG code > and particually polygon heavy models. I'd like to have a go at some > optimisation (i have a fair knowledge of C++), but i need a place to start, > or better some people to help me. I'd say the terrain mesh is a major polygon heavy "model". :) We don't have any LOD system in place so as soon as you try to increase the visibility to about 50-80 km the sim slows to a crawl. I'm lucky if I get 1 frame every 5 seconds. Not everyone lives in smog filled cities. Paul ------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Do you grep through log files for problems? Stop! Download the new AJAX search engine that makes searching your log files as easy as surfing the web. DOWNLOAD SPLUNK! http://ads.osdn.com/?ad_id=7637&alloc_id=16865&op=click _______________________________________________ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
