Re: [OSM-talk-fr] [Technique] Fwd: [OSM-dev] Help with implementation of multiplicatively weighted Voronoi diagram for nominatim

[Benoît ROUSSEAU]

Bonjour,     LA référence c'est http://www.cs.cmu.edu/~quake/triangle.html. Peut être voir avec son auteur.     Voir aussi pour info le site dans son ensemble (une des pages) : http://www.voronoi.com/wiki/index.php?title=Voronoi_Applications. Benoît R. Sont adresse openstreet...@brian.quinion.co.uk n'est pas la bonne je vous laisse lui transférer. Emilie Laffray a écrit : Bonjour, je sais qu'il y a des gens tres pointus ici, donc je me permets de reposter. Le createur de Nominatim a besoin d'aide pour implementer un weighted Voronoi diagram utilisant CGAL. Donc s'il y a des gens qui peuvent aider, lui envoyer un message. Emilie Laffray ---------- Forwarded message ---------- From: Brian Quinion <openstreet...@brian.quinion.co.uk> Date: 21 July 2010 13:20 Subject: [OSM-dev] Help with implementation of multiplicatively weighted Voronoi diagram for nominatim To: d...@openstreetmap.org Hi, I've been trying to get a working implementation of a multiplicatively weighted Voronoi diagram written now for nearly a week and I'm really struggling. The intention is to use it to improve the the indexing quality and speed of nominatim with regards to mixing city, town and village points in some layers - I'm sure many of you have noticed the current problem were towns and villages end up inside city boundaries (producing weird addresses). I have a working implementation for a non-weighted algorithm using Fortune's algorithm [1] - if anyone has the time and maths skills to adapt that it would be wonderful (can Fortune's algorithm even do multiplicatively weighted Voronoi diagrams?) beyond that I've been looking at adapting the demo from cgal [2] but I'm struggling due to my poor C++ skills (and the fact that the c++ code makes use of insane numbers of templates).  For someone who is really good with c++ or already familiar with cgal it would probably be fairly easy. Alternatively if anyone is aware of any other implementation or is able to implement anything based on a different library that would also be good.  I think it really has to be c or c++ - anything else would be tricky to integrate.  Potentially an implementation in R [3] using the postgresql module is another possibility. If anyone can help let me know - otherwise I will struggle onwards and hope to get somewhere! --  Brian [1] http://en.wikipedia.org/wiki/Fortune's_algorithm [2] http://www.cgal.org/Manual/latest/doc_html/cgal_manual/Apollonius_graph_2/Chapter_main.html [3] http://www.r-project.org/ _______________________________________________ dev mailing list d...@openstreetmap.org http://lists.openstreetmap.org/listinfo/dev _______________________________________________ Talk-fr mailing list Talk-fr@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk-fr Ce message entrant est certifié sans virus connu. Analyse effectuée par AVG - www.avg.fr Version: 9.0.851 / Base de données virale: 271.1.1/3019 - Date: 07/21/10 08:36:00

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