[mapserver-users] RE: Rendering overlapping data

[Ludwig Kniprath]

I dont't think, Mapserver has the out-of-the-box possibility to render the overlapping parts of polygons in a special way. Perhaps you could try to create a separate layer (f. e. in Postgis with a special geo-query), that just shows these overlapping parts. But also then I think its difficult to query and to render the case, that three or more polygons do overlap.

Ludwig

>
>Message: 2
>Date: Mon, 21 Dec 2009 17:22:44 +0100
>From: Peter Hopfgartner <peter.hopfgartner at r3-gis.com>
>Subject: [mapserver-users] Rendering overlapping data
>To: mapserver-users at lists.osgeo.org
>Cc: d'Orio Pietro <pietro.dorio at r3-gis.com>
>Message-ID: <4B2FA0D4.7020700 at r3-gis.com>
>Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>
>Dear list members
>
>We would like to visualize a layer with data, where polygons with 
>different classes may overlap. Using transparency, "new" colors are 
>introduced, e.g. if I overlap a blue and a red polygon I get an violet one.
>
>Is there a way to show overlapping polygons in stripes with cycling 
>colors, or as a checker board? How do people handle this?
>
>Regards,
>
>Peter
>
>-- 
> 
>Dott. Peter Hopfgartner
> 
>R3 GIS Srl - GmbH
>Via Johann Kravogl-Str. 2
>I-39012 Meran/Merano (BZ)
>Email: peter.hopfgartner at r3-gis.com
>Tel. : +39 0473 494949
>Fax  : +39 0473 069902
>www  : http://www.r3-gis.com