Thanks to everybody for the feedback. For now I think I'm going to be making holes by hand. That is, I will create the surface using multiple quads patched together so that the area surrounding the hole is covered with a separate patch.
I tried my hand at POVRay many rears ago. Along with a few statements I had read elsewhere, I had been given to believe "everybody" did CSG. When I encountered scene graph packages a couple years ago, I was surprised to find that they don't do this "out of the box". Now that I have a better appreciation for the magnitude of the challenge as well as the limitations of CSG, I am less surprised. Just contemplating the notion of generic code for handling solids of arbitrary shape with holes is mind boggling. The tesselation code in the OSG example appears to provide a potential solution for some situations. When I ran the examples, the animated scene rotation was jumpy, suggesting it requires a lot of processing. Perhaps that can be done once and "cached"? Here's an example of the kind of problem I am currently dealing with. I want to model a building constructed of column and spandrel assemblies, as shown here: http://www.kolumbus.fi/totuus/img/wtc-wall.jpg There are literally thousands of these exterior panels. Depending on LOD, I want to be able to zoom in on any given detail and have it depicted with sufficient accuracy and precision to accurately represent the design and implementation of the structure. Though it is no an immediate goal, I would like the be able to modify the geometry of one of these assemblies (for example if it happens to be thrown 700 feet due to some catastrophic event, and becomes deformed by the forces involved. I therefore want my geometric model to be as faithful to the physical reality as is possible (whatever that means). On Tuesday 24 October 2006 18:02, Geoff Michel wrote: > or you could use the osgTesselator to make holes. See the tesselator > example. The samples have lots of holes in. > > Or you can use the .dw format and the Design workbench modeller which saves > things with holes in. The "flat plank of steel" need not be flat in DW. > I have examples with hundreds of of holes in. > > (www.artifice.com design workshop lite will do it) > > NB Someone has used my email- only used for OSG stuff- to send me details > on a 'performance' enhancing drug. Dont do that. > > G _______________________________________________ osg-users mailing list [email protected] http://openscenegraph.net/mailman/listinfo/osg-users http://www.openscenegraph.org/
