[GRASS5] Grass Delaunay triangulation in 3d

[Robin Schroeder]

Dear Grass Developer's List,

On Behalf of Mike Zoldak:

I'm new to open source GIS and have been working with the GRASS 6.0 beta for a couple of weeks now.  I like what I've seen so far.  I want to take advantage of  it's OS nature and have a task where it seems I must.  

I have 3D vector points and need to create a triangulation that meets Delaunay criteria in 3 dimensions.  The next step in my process is to extract node and edge tripletes and write them to an ascii file, so I don't need to construct a truly functional surface for visualization purposes.

The v.delaunay with the -l option almost meets my purposes.  It meets the criteria in 2D, but not 3D.  The resultant topology drops the z-coord that was  in the original point file when creating the nodes in the output line file.  I would like to modify v.delaunay so that the z-coord is used in the calculation and (naturally) kept in topological structure.

To this end, I download the latest snapshot, grass-6.0.cvs_src_snapshot_2005_02_12, and started to examine the C code for v.voronoi (the broader function set).  But I am no programmer, let alone C programmer, and couldn't quite follow the code.  If one of the developers is not too busy, I'd like some advice on resources I could use, specific alterations (if not too extensive), and steps for compiling the altered code with a different name so that I can use it in GRASS.

Thanks;
Mike Zoldak
International Institute for Sustainibility
Arizona State University


Robin Tori Schroeder
Senior Software Developer
International Institute for Sustainability
Arizona State University 
480-727-7290
robin.schroeder at asu.edu