[R-sig-Geo] Any plans to provide access to CGAL in R?

[Michael Sumner]

On Mon, 10 Jul 2017 at 22:03 Robin Lovelace <rob00x at gmail.com> wrote:

> Hi all,
>
> I've just been made aware of the CGAL <http://www.cgal.org/> C++ library
> for computational geometry.
>
>
Hi Robin, we've discussed this here:

https://github.com/r-spatial/discuss/issues/6

FWIW a few years ago I did some simple Rcpp tests:

https://github.com/r-gris/cgalgris

Then I discovered RTriangle (it and TDA use the same underlying library)
and that provides the main thing I was after, now in package sfdct and
applied for more general use here:

https://github.com/r-gris/rangl

There is a lot you can do with a constrained triangulation, it's a "hammer"
and sometimes overkill but it's extremely flexible and powerful. I'm happy
to flesh out examples for problems you think might be solvable with it to
help promote why CGAL would be useful in R.

I'm very interested in general forms for these data, and the idea is to put
all the 3D rangl stuff on this footing eventually:

https://github.com/mdsumner/sc

tidygraph is a very good example of how we can modernize these indexed data
structures, and other newish packages icosa, webglobe, dggridR, also touch
on this "mesh" way of working. For that matter spdep and GEOS work that way
internally, but we only have fragments of the concept available at an R
level.

Simon Urbanek has s-u/rcgal on github but it doesn't expose very much.

Cheers, Mike.






> It seems to be able to do some things that may be useful to some readers of
> of this list, as outlined in this overview of a syllabus based on CGAL:
> http://delivery.acm.org/10.1145/2930000/2927362/a8-alliez.pdf
>
> I've found some non-CRAN packages that link to it but nothing that seems to
> provide access to all CGAL functions (listed below). Any ideas if there are
> plans afoot for this or even if it's worth doing?
>
>
>    - http://kien-kieu.github.io/lite/rlite.html
>    - https://github.com/rcqls/EBSpatCGAL
>
> There is also TDA on CRAN:
> https://cran.r-project.org/web/packages/TDA/index.html
>
> And a C++ library that claims to support it for simple features (found by
> looking for support in QGIS): https://github.com/Oslandia/SFCGAL
>
> Plus a question on StackExchange:
>
> https://stackoverflow.com/questions/14463590/cgal-tools-is-there-an-interface-to-cgal-or-equivalent-toolset-in-r
>
> Thanks in advance,
>
> Robin
>
>         [[alternative HTML version deleted]]
>
> _______________________________________________
> R-sig-Geo mailing list
> R-sig-Geo at r-project.org
> https://stat.ethz.ch/mailman/listinfo/r-sig-geo
>
-- 
Dr. Michael Sumner
Software and Database Engineer
Australian Antarctic Division
203 Channel Highway
Kingston Tasmania 7050 Australia

	[[alternative HTML version deleted]]