Steiner Point insertion

[ihmc3jn09hk]

Hi, I am looking for alternative and more modern delaunay triangulation library instead of Triangle. It is awesome and extremely fast. I have been using it for a while but it's kind of old now and the memory management is still 32bit.
I found this CDT project and everything looks promising. Yet I could not find any parameter/function that allows insertion of Steiner Points/Quality control during triangulation. Could you guide me out?

[artem-ogre]

Hi,

Thanks for the question.

Triangulation refinement is not implemented in CDT. I have it on my TODO with the highest priority (after performance improvements). It is nice to know that this feature is demanded :)

Any help is welcome and appreciated: pull requests, algorithm implementation suggestions or any other additional information.

There are couple of 64bit patches for Triangle floating around on github. I can check where I’ve seen one if you are interested. One major Triangle shortcoming for me is that it does not use a proper permissive software license. And Mr. Shewchuk is impossible to reach (I tried really hard for months).

Did you have a chance to do any perf comparisons with Triangle? It would be really interesting to know how it compares.

[artem-ogre]

I'm closing this issue for now. Please let me know if you have any further questions.

[starseeker]

Does poly2tri's implementation have anything useful in this regard? They do support Steiner points, although as far as I know they don't use robust predicates... https://github.com/jhasse/poly2tri

[starseeker]

In a similar mode, does CDT support specifying hole polygons? I end up needing both holes and Steiner points in the application in which I use poly2tri (triangulation of trimmed NURBS surfaces).

[artem-ogre]

Thanks for the interest @starseeker!

Inserting Steiner points is a rather straight forward algorithm. We don't need it for our needs right now and unfortunately there is not enough free time to just implement it. Hence a 'help wanted' label on this issue :)

Removing holes is supported and done automatically with one condition: hole polygons and boundary polygon edges need to be constraint edges. See eraseOuterTrianglesAndHoles. It is much easier to use and works for all the use cases we had so far.

[Islam0mar]

WIP #133.