Hi John, On Tue, Aug 17, 2010 at 9:37 AM, John Water <[email protected]> wrote: > from now, speed is still not good, and cull time also high. anything can I do > now ?( cut down transform node ??)
It very much sounds like your scene graph is too fine grained for performance. Batching geometry and state together will most likely give you a significant boost. You don't mention the number of vertices in your model, and the way you discussed the triangle/triangle strip is rather too open ended to make conclusions from, but at a guess it doesn't sound like vertex count is rather high. Modern graphics cards can comfortable handle a million vertices per frame at 60Hz, so at guess the numbers you have a way below this and shouldn't represent a bottleneck. Given that geometry complexity may well not be a performance issue then I'd guess that use of LOD's probably won't help much unless the LOD's are able to provided a simplified the subgraph and state associated for the lowest level of detail. Use of transforms should just limited to dynamically moving objects, for all static objects flatten the transforms, the Optimizer can do this for you but you must set the DataVariance on the Transform to STATIC to give it the hint that it can optimize it away. Use of the Optimizer should be seen as a last resort though - if you build a well balanced scene graph to start with then the optimizer won't have anything to do. The topic of optimization is huge topic, something that has been touched on many times over the years here so have a search through the archives for pointers. There really shouldn't be any reason why you shouldn't be able to hit a solid 60Hz with your app - you just need to build an efficient scene graph. Robert. _______________________________________________ osg-users mailing list [email protected] http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
