No, 1 to 1 mapping of primitives isn't possible because OpenGL doesn't render concave polygons correctly (in practice GL_POLYGON is the same as GL_TRIANGLE_FAN). Tesselation is possible via GLU but very slow so we need to be careful about how we use that. Most models I've come across have many triangles and quads but few polygons >=5 vertices. If we apply triangulation to those few polygons then most models will be unaffected. For quads I imagine it would be possible to write some fast specialised code to see if they should be split across vertices (0,2) or (1,3) so that loading times remain bearable. However, if your content provider could just produce models that are already suitable for real-time rendering that would be best ;)
On 5 July 2010 09:09, Sukender <suky0...@free.fr> wrote: > Hi all, > > The FBX reader seems to interpret FBX polygons as triangles. Well I guess > this should not be, as 1-to-1 mapping of primitives is possible (as far as I > know), but this is not really an issue. What is an issue is that concave > polygons are not intepreted the right way. I think about two solutions: > 1. Use tessellation code to get correct "splitting" > 2. Do the 1-to-1 mapping of primitives > > Am I right ? > Other ideas? > Anyone having time for this? > > Thanks folks! > > Cheers, > > Sukender > PVLE - Lightweight cross-platform game engine - > http://pvle.sourceforge.net/ > _______________________________________________ > osg-users mailing list > osg-users@lists.openscenegraph.org > http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org >
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