Hi, Just a short comment: remember that the Voronoi function in MapInfo actual can use a closed object, set as target, as clipping/extension area.
So if you manually or thru code, start by making a layer editable, selects an closed object from this layer, and then selects the points to use for voronoi creating, MapInfo will make sure that the "inside" of the target area is filled with the voronoi objects. This is a neat and often overlooked feature, that also is well describes in the manual ;-) Peter Horsbøll Møller GIS Developer, MTM Geographical Information & IT COWI A/S Odensevej 95 DK-5260 Odense S. Denmark Tel +45 6311 4900 Direct +45 6311 4908 Mob +45 5156 1045 Fax +45 6311 4949 E-mail [EMAIL PROTECTED] http://www.cowi.dk/gis -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Nabors, Steve Sent: Wednesday, May 17, 2006 3:47 PM To: Uffe Kousgaard Cc: MapInfo-L@lists.directionsmag.com Subject: RE: [MI-L] Voronoi I agree with Uffe, Looking at the points, you have an idea, but you never really know how big and what rotation the voronoi MBR will be. So if the voronoi MBR is "clipping" areas that you want included then you simply need include more existing points beyond the area of interest. If you don't have any more points outside the are of interest, simply put some new points well outside your area of interest and include them in your selection. So the rule of thumb is, always include points well ouside of the area of interest or create dummy/dataless records to allow you to do the same. A classic example would be land based points near the ocean and part of the coast line gets "clipped" because there are no points out in the ocean to increase the vornoi MBR. Voronoi creates "grains of growth" or polygons that are the result of a bisection or half the distance from any one point, to another. In the ocean problem, simply put some dataless points out in the ocean, so that at least half the distance between any ocean points and land points is still out over the water. -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Uffe Kousgaard Sent: Wednesday, May 17, 2006 4:52 AM To: Mapinfo-L Subject: Re: [MI-L] Voronoi Just add some additional points far away from your own points and then clip the resulting polygons with whatever you had in mind for additional distance. Kind regards Uffe Kousgaard www.routeware.dk ----- Original Message ----- From: "Jaromir Svasta" <[EMAIL PROTECTED]> To: <mapinfo-l@lists.directionsmag.com> Sent: Wednesday, May 17, 2006 10:51 AM Subject: [MI-L] Voronoi > Hi listers, > > Does anyone of you have some nice code (MB or VB) for creating voronoi > polygons from points? <Create Object As Voronoi> stetement in MapBasic is > not sufficient for my purpose, because it limits the outer boundary of > polygons to the point's MBR, I need to extend it some distance. > > -- > Jaromir SVASTA > Hydrogeologist > Geological Survey of Slovak Republic > Mlynska dolina 1 > 817 04 Bratislava > Slovak Republic > > Tel: +421 2 59375326 > Mobile: +421 908783589 > Fax: +421 2 54771940 > _______________________________________________ > MapInfo-L mailing list > MapInfo-L@lists.directionsmag.com > http://www.directionsmag.com/mailman/listinfo/mapinfo-l _______________________________________________ MapInfo-L mailing list MapInfo-L@lists.directionsmag.com http://www.directionsmag.com/mailman/listinfo/mapinfo-l ______________________________________________________________________ This e-mail has been scanned by Verizon/MessageLabs Managed Email Service. ______________________________________________________________________ This e-mail has been scanned by Verizon/MessageLabs Managed Email Service. _______________________________________________ MapInfo-L mailing list MapInfo-L@lists.directionsmag.com http://www.directionsmag.com/mailman/listinfo/mapinfo-l _______________________________________________ MapInfo-L mailing list MapInfo-L@lists.directionsmag.com http://www.directionsmag.com/mailman/listinfo/mapinfo-l
