Hi John, Thanks for the additional info.
Intersecting objects at infinity is a curious thing, I hadn't thought about needing a ratio with a w component. The barycentric coordinates used for the vertices surrounding the intersected triangle can safely stay as a float or double, although I'd need to look up the maths involved to know about the interpolation of homogeneous coords. In terms of objects at infinity being effectively 2D, for ray intersections you can think about all objects being 2D if you change the coordinate frame so the ray is along the a local Z axis, then we you transform all the geometry into this coordinate frame you'd just test against XY and depth no longer becomes an issue. It might be reflecting on the maths involved might help refine what the API and class structure should be. Leave this with me, I have your implementation to work with, and can ponder on the public interface to it and how we construct the back end. I can't promise anything immediate though. If you mathematical friend has any further suggestions that let me know. Robert. _______________________________________________ osg-submissions mailing list [email protected] http://lists.openscenegraph.org/listinfo.cgi/osg-submissions-openscenegraph.org
