From: erwan b. <erw...@gm...> - 2009-04-30 19:15:07
|
Dear friends, To complete Thomas a new triangulation package has been developed by Jean-Yves Martin (Professor at Ecole Centrale de Nantes). It will be fully available in 2 weeks. The beta code is here : http://geosysin.iict.ch/irstv-trac/browser/platform-contrib/jdelaunay. It includes : - DT - CDT ( static or dynamic) The user can set constraints on angle and triangle size or uses an algorithm to delete flat triangle. The output edge, node and triangle are stored in a topological planar data model. For example you can know which triangles are adjacent to an edge. The output format is an xml file but the lib has been also linked to GDMS to produce shapefile and other supported formats. The license is GPL3. The JDelaunay lib is used in a french research project in spatial hydrology to evaluate the impact of runoff pathway in urban areas. Have a look here : http://brehat.ec-nantes.fr/avupur/doku.php?id=exploitation_du_graphe_-_indicateurs A paper has been submited to the super OGRS symposim ;-) Feel free if you have any questions. R1. -- Responsable de l'atelier SIG Docteur en géographie, spécialité géomatique École Centrale de Nantes Institut de recherche en sciences et techniques de la ville http://www.irstv.cnrs.fr/ http://www.orbisgis.org http://r1.bocher.free.fr http://www.ogrs2009.org 2009/4/30 Thomas Leduc <tho...@fr...> > 2009/4/29 Michaël Michaud <mic...@fr...> > >> Hi Martin, >> >> You may already know the benchmark done by Erwan's team with some java >> implementations ( >> http://conference.osgeo.org/index.php/foss4g/2008/paper/view/282/177) >> It eventually shows the triangulator I have written a few years ago >> (available on http://geo.michaelm.free.fr/OpenJUMP/resources/) is very >> fast (I have to add it is not 100% robust as it sometimes fails for large >> datasets - more than 100k points) >> They also wrote a more recent paper about their new implementation for >> orbisgis : >> http://hal.archives-ouvertes.fr/docs/00/32/95/03/PDF/CDT-paper.pdf >> >> > good morning, > Indeed, in 2008, several (C)DT implementations (including famous "Triangle" > one) have been coupled with OrbisGIS so as to compare performances. It seems > the one of Michaël (thanks to him for his useful help) was the fastest one. > I've also tried to "enhance" his own implementation adding a sweepline and a > (not fully debug yet - job was postponed) soft breakline insertion method. > All those dev will be published asap. > > -- > > -- > Thomas LEDUC > > > ------------------------------------------------------------------------------ > Register Now & Save for Velocity, the Web Performance & Operations > Conference from O'Reilly Media. Velocity features a full day of > expert-led, hands-on workshops and two days of sessions from industry > leaders in dedicated Performance & Operations tracks. Use code vel09scf > and Save an extra 15% before 5/3. http://p.sf.net/sfu/velocityconf > _______________________________________________ > Jump-pilot-devel mailing list > Jum...@li... > https://lists.sourceforge.net/lists/listinfo/jump-pilot-devel > > |