Frederic Bouvier wrote: > Quoting Stewart Andreason : >> leee wrote: >>> On Thursday 15 February 2007 21:45, Berndt, Jon S wrote: >>>> What's a realistic upper limit for polygon count now for an aircraft >>>> model? 5000? 10000? 25000? >>>> >>>> What's definitely "out"? >>>> >>>> Jon >>> AFAIK, current top-end vid cards can handle several million textured polys >>> (typically between 1 - 3 M) >>> >>> For a single model - don't worry too much, for n models as few as possible. >>> >>> LeeE >> Well, that's interesting. >> >> Lee, have you ever gotten a SegFault from a large .ac file? >> I don't think I ever got any reply to my gdb backtrace I posted Jan.26, so I >> still am interested in knowing about upper limits on polygon counts. > > There is a 32k vertices limit for individual objects in plib. But you can have > as many objects as you want. Just don't merge them. I don't remember if there > is > an optimization pass in the ac3d loader that would aggregate individual > triangle > of the same OpenGL state.
Ok, good. That explains a couple meshes I downloaded and tried to get working, 41000 and 50000 vertices is too many. Thus, I kept working on the model I already had for 2 years. 32,768 maximum vertices. Hmmm... I did get segFaults (for a long time) until version 19, when the exported .ac file (less one mesh object) finally loaded, and version 20, when I was able to switch over from .3ds exports to .ac. The count in this time frame was from 38,100 to 34,700 polygons, and around 22,300 vertices is when the .ac file started working. But it was not a definite number, some files with more did load, and some with less did not. I have that much documented in my archived notes. Either I'm missing something, or there is another key to the failure, yet to discover. I suspect: Too many vertices too close together, or holes in the mesh, with overlapping polygons and reversed normals conflicting for outward appearance. Having re-faced those areas too many times, I scream enthusiastically "All GONE!!" I was hoping the backtrace could provide insight. I could re-generate some .ac files for testing? But no longer a priority, as it is all in the past. Back to you, Stewart ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys-and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
