Hi Andy, I'm tempted to just convert LineSegment to use Vec3d, this would ensure that all transformation done of LineSegments would retain good accuracy, often we do world to local intersection tests where the world is a whole earth model. Changing to doubles in the Vec3 elements should tackle the intersection issues as well.
Thoughts? Robert. On Feb 6, 2008 9:50 PM, Andy Skinner <[EMAIL PROTECTED]> wrote: > This is to address what I've been asking about on the users list. We've > got cases where the float math just isn't enough to do the intersections > properly. I had to convert everything to doubles for it to work. > > One optimization is that Vec3d versions of _s, _e, and _s-_e could be > stored in the LineSegment and calculated when needed in an intersection. > The intersect() method is const, so I didn't do it here. > > I am a little less sure of the intersect method that takes 3 Vec3s and a > float reference. I saw it did a-b one place and b-a another, and I used > a Vec3d for this and used its operator- for the second occurrence. I'm > not sure how much of this is worth it. > > If those who do a lot of these intersections could time this and tell me > how it does, I'd appreciate it. > > andy > > > _______________________________________________ > osg-submissions mailing list > [email protected] > http://lists.openscenegraph.org/listinfo.cgi/osg-submissions-openscenegraph.org > > _______________________________________________ osg-submissions mailing list [email protected] http://lists.openscenegraph.org/listinfo.cgi/osg-submissions-openscenegraph.org
