On Jul 16, 2013, at 11:59 AM, Tom Browder wrote: > I just found this reference on O'Reilly's Safari: > > An Introduction to NURBS > By: David F. Rogers > Publisher: Morgan Kaufmann > Pub. Date: July 21, 2000
That's as good a place to start as any. Just be aware that there's been more than a decade of research since that book was published. In particular, there was some game-changer research published in RT'06 that is what vitalized my own interest in making BRL-CAD become hybridized. Before then, all the research indicated they NURBS were a crazy complicated and very slow representation format. After, just crazy complicated. Even our old 'bspline' primitive implemented support the old way and exemplified the problems. It's a book-keeping and processing nightmare. Memory incoherent. Very impractical for directly analysis work, especially via ray tracing. The old approach was relatively straight-forward but involved converting NURBS geometry into sets of BSpline surface patches, which are far more simple to evaluate. The new research showed one can evaluate (via various methods, active area of research) the NURBS surfaces directly and do so really fast. Fast NURBS ray tracing was a possibility. A couple years ago, I compared our new brep/nurbs implementation with our old bspline/nurbs one and it was already about two to three orders of magnitude faster. Evaluation times going from several minutes to sub-second! And we still haven't really worked on optimization yet. Cheers! Sean ------------------------------------------------------------------------------ See everything from the browser to the database with AppDynamics Get end-to-end visibility with application monitoring from AppDynamics Isolate bottlenecks and diagnose root cause in seconds. Start your free trial of AppDynamics Pro today! http://pubads.g.doubleclick.net/gampad/clk?id=48808831&iu=/4140/ostg.clktrk _______________________________________________ BRL-CAD Developer mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/brlcad-devel
