Peter Amstutz wrote: > Is there a way to use an axis-aligned bounding box (AABB) for the coarse > bounding volume rather bounding spheres, for line segment > intersections? In my application my primary geometry is made up of > terrain tiles which are naturally axis aligned and buildings which tend > to be rectangular prisms. In both cases, my intuition is that even the > worst-case AABB is still going to represent a much tighter bound than > the best-case bounding sphere, leading to unnecessary and expensive > tests against the actual geometry. It's not clear that simply > reorganizing and optimizing the scene graph would help much in this > case, since the buildings are clustered in a town such that bounding > spheres will naturally tend to overlap, as well as extend out into the > street. Any ideas on how to handle this situation more efficiently?
I think the reason for the bounding spheres is that it is a very efficient-to-compute formula -- many times more efficient than AABB. Are you worried about intersection efficiency during cull phase, or during intersection testing, or where? Have you actually experienced a measurable problem or are you speculating that there will perhaps be one? > Thanks, > - Peter -- Chris 'Xenon' Hanson, omo sanza lettere Xenon AlphaPixel.com PixelSense Landsat processing now available! http://www.alphapixel.com/demos/ "There is no Truth. There is only Perception. To Perceive is to Exist." - Xen _______________________________________________ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
