> Date: Fri, 14 Feb 2003 14:28:21 -0700 > From: White Morph <[EMAIL PROTECTED]> > > If Java3D does use FIST code for triangulation, then I guess it doesn't do > the sorted or random optimization that is mentioned in the paper, because > each time I run a program, it always get the same triangulation, on the other > hand, if I change the starting vertex, it normally gets a different > triangulation.
GeometryInfo uses a Triangulator constructor that sets the sorted and random ear modes to false. I don't know the reason behind this choice; there may have been some problem with those modes that it made it not worth using for Java 3D. Paul might have some insight into this. If you think this might be a bug, the best thing to do is submit a bug report so we'll have some justification for looking into this complex bit of code. Is there a problem in your application that would definitely be solved by using sorted or random ear optimization? Triangulator is probably not using the latest version of FIST. It appears to be using code derived from FIST 1.6. The last update to the Java 3D derived code was a bug fix on February 25 2002. > By the way, I wonder why Java3D doesn't use the Constrained Delaunay > Triangulation, which even the author of FIST admits has better triangulation > quality. Good question. We've been using the FIST code since early 1998. It was probably a matter of what code was already available from the relationships that we had at the time vs. the resources that we had to develop a robust triangulator ourselves. Triangulators are notoriously difficult to get right for "industrial-strength" applications. Again, Paul might have some insight into this. The Triangulator class is a utility, not part of the Java 3D core, so if you need to use an alternative triangulation algorithm there's no technical reason why you can't substitute whatever you need. -- Mark Hood =========================================================================== To unsubscribe, send email to [EMAIL PROTECTED] and include in the body of the message "signoff JAVA3D-INTEREST". For general help, send email to [EMAIL PROTECTED] and include in the body of the message "help".
