Hi Dirk, Wonderful! Thanks for the fix. It's working great. E.
-----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Dirk Reiners Sent: Wednesday, June 27, 2007 09:37 To: [email protected] Subject: Re: [Opensg-users] SplitGraphOp and Bounding Volumes Hi Eric, [EMAIL PROTECTED] wrote: > Hello all, > I've been working with the SplitGraphOp and have a few questions on > it's intended use and expected behavior. > > Questions: > 1) does RenderAction::setVolumeDrawing(true) ignore the bounding volume > of geometries, if so, how do I visualize the bounding volumes of an > object after it has run through SplitGraphOp. Hm, it should draw them. > 2) are there known limitations/problems/errors with using SplitGraphOp > on very large models? With OBJ files? VRML files? I get different > results depending on whether the model was loaded as VRML or OBJ (at > least in terms of what setVolumeDrawing() shows). It does eat up quite a bit of memory, but it should be repeatable. Concerning OBJ vs VRML: the scene graphs of OBJ and VRML files looks different (MaterialGroups etc), so I wouldn't be surprised to see some differences. > 3) when I turn on volume drawing I get a brown/yellow box moving around > my scene wildly and seems to be attached to the camera but not identical > to it. what does this color represent? It looks like some form of > frustum. (see attached) That's supposed to be the frustum, yes, but apparently it's not rendered in the right position. Not sure what's wrong there, but I don't want to spend time fixing it right now (too much going on). > Background: > > I have several large models from Pascall Mueller's site > (http://www.vision.ee.ethz.ch/~pmueller/wiki/CityEngine/DownloadModelsPompei i). > I would like to break up these models using SplitGraphOp to make use of > frustum and occlusion culling. when I run SplitGraphOp on them, the > number of occlusion tests never go above 1, and the number of nodes > drawn is a little higher (7nodes vs. 28nodes). Sadly, the # of nodes > doesn't represent my "max_polygon" value nor does the # of nodes drawn > change during runtime as I add/remove things from view. > > Using the OpenSG Traversal example, it states that the # of nodes > before/after is the same for this model. So, I tried a simpler model, a > tessellated sphere loaded from file, and received slightly different > results. It ocassionally broke up the object into many parts, but the > drawn volumes didn't update. I still had only one bounding box drawn. > > How have others approached such a scenario? Any insight would be greatly > appreciated. That's what the SplitGraphOp is meant for, but sadly it has not gotten a lot of exercise since it's initial writing many years ago, so I would not be too surprised if it didn't quite work the way it's expected. I tried it on the Pompeii models and I found the problem there: the SGO didn't do anything if the root node was a leaf. I fixed that (committed). Hope it helps Dirk ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/ _______________________________________________ Opensg-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/opensg-users ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/ _______________________________________________ Opensg-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/opensg-users
