Looking for Delaunay triangulation module...

[Grant Edwards]

Can anybody point me to a Delaunay triangulation module (for
Win32)? I'm currently using http://flub.stuffwillmade.org/delny/ under Linux, but I have
been unable to find a build for Windows. I don't have the tools
(or skills) to build libqhull and Pythion extensions on Win32).

I've also found the delaunay module in scipy's "sandbox". I
could never get that module to work under Linux, and I can't
build it for Windows anyway.

So for lack of a delaunay module, I'm stuck trying to port my
application to Win32.

I've spent some time Googling and found various references to
pur Python delaunay modules that were abandoned because they
were slow (though I haven't been able to find any of the actual
modules). Slow is better than none.

 

[Grant Edwards]

So for lack of a delaunay module, I'm stuck trying to port my
application to Win32.

I've found that VTK contains a Delaunay triangulation module,
and Entought Python includes VTK, so that's next on my list of
things to try as soon as VTK finishes building on my Linux box
(where I do all of my actual development).

 

[Lawrence D'Oliveiro]

So for lack of a delaunay module, I'm stuck trying to port my
application to Win32.

Why not run it under Cygwin?

 

[Grant Edwards]

Why not run it under Cygwin?

I'm hoping there is an easier way than trying to build a
half-dozen large Python extensions (and their supporting
libraries) under Cygwin.

It looks like VTK might do the trick. I can do the
triangulation, I just can't figure out how to get the data out
of the object containing the results. VTK isn't very
Python-friendly at all.

 

[drobinow]

I'm hoping there is an easier way than trying to build a
half-dozen large Python extensions (and their supporting
libraries) under Cygwin.

Well, that's what Cygwin is for -- to make it easy to do that.
What's not working?

I'm also not clear what your problem is with Delny with qhull under
Windows.
What errors have you gotten?
All the tests pass for me.

 

[Grant Edwards]

Well, that's what Cygwin is for -- to make it easy to do that.

I know that's its intent. In my experience it doesn't succeed
very well. I've spent years supporting a set of development
tools under both Cygwin and Linux. The Cygwin versions are a
continuous pain for everybody involved.

What's not working?

I have never tried to run my application under Cygwin.

AFAICT, many of the Python packages I use aren't available as
packages for Cygwin, and I don't really want to spend the time
trying to build and maintain them.

My experiences building things from source in Cygwin haven't
been good in the past, and I have zero experience bundling up
Cygwin-hosted applications for delivery.

I have used an application suite under Windows that comprised
Cygwin apps and a bundled Cygwin installation, and it was a
total distaster. Perhaps that was just a singularly bad
example, but it sure made it seem like using Cygwin as a
platform for delivering Windows applications was a bad idea.

I'm also not clear what your problem is with Delny with qhull
under Windows.

I wasn't able to find a copy of Delny and qhull library for
Windows. I did find postings asking where one could be found.
Those postings went unanswered.

 

[Robert Kern]

Can anybody point me to a Delaunay triangulation module (for
Win32)? I'm currently using http://flub.stuffwillmade.org/delny/ under Linux, but I have
been unable to find a build for Windows. I don't have the tools
(or skills) to build libqhull and Pythion extensions on Win32).

I've also found the delaunay module in scipy's "sandbox". I
could never get that module to work under Linux, and I can't
build it for Windows anyway.

I'm working on it today. I'm going to break it out into a separate package. If
you can remember what problems you had, I'd like to fix them. I'm clearing up a
number of (really dumb) memory leaks.

--
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
that is made terrible by our own mad attempt to interpret it as though it had
an underlying truth."
-- Umberto Eco

 

[Grant Edwards]

I'm working on it today. I'm going to break it out into a
separate package. If you can remember what problems you had,
I'd like to fix them. I'm clearing up a number of (really
dumb) memory leaks.

I'm sorry I don't remember what the problems were. It was some
time ago (probably 14-16 months) when I was trying to use the
module. After spending a day or two on it, I switched to the
Delny module (which I had used in the past).

I do have Dlaunay triangulation working using VTK (which is
included in Enthought Python), but I haven't been able to
figure out how to extract the triangle list from the object
containing the resulting triangulation. The object method that
people on the VTK mailing list tell me to call isn't available
in the Python binding.

 

[Grant Edwards]

I do have Dlaunay triangulation working using VTK (which is
included in Enthought Python),

Well, of course that doesn't work under Windows either. Doing
an "import vtk" crashes the python interpreter.

How people get any work at all done using Winodows is beyond me...