[geos-devel] Perhaps a stupid question about polygons...
sdlime at comcast.net
Mon Jun 28 18:52:46 EDT 2004
I've already done it to export as GML 2.0. Your idea would work except
MapServer polygons can have multiple outer rings too in the case of a
lake with multiple basins and islands in each basin (which could also
contain holes). If I recall I ended up looking at a single vertex in
each part and counting the number of other parts it falls into.
On Jun 28, 2004, at 5:26 PM, Martin Davis wrote:
> Yup, absolutely.
> This shouldn't be too much of a showstopper tho. It's easy to write
> code to detect which is the outer shell. I think the easiest algorithm
> would just be to take the ring with the largest x or y extent.
> Martin Davis, Senior Technical Architect
> Vivid Solutions Inc. www.vividsolutions.com
> Suite #1A-2328 Government Street Victoria, B.C. V8T 5G5
> Phone: (250) 385 6040 - Local 308 Fax: (250) 385 6046
>> -----Original Message-----
>> From: Stephen Lime [mailto:sdlime at comcast.net]
>> Sent: June 28, 2004 3:20 PM
>> To: geos-devel at geos.refractions.net
>> Subject: [geos-devel] Perhaps a stupid question about polygons...
>> Hi all: The recent thread about polygons and holes got me thinking.
>> Does building polygons in geos require the client to know if
>> a ring in
>> a particular polygon is inner vs. outer? MapServer makes no provision
>> for this since it's not necessary for rendering features nor simple
>> intersection tests.
>> geos-devel mailing list
>> geos-devel at geos.refractions.net
> geos-devel mailing list
> geos-devel at geos.refractions.net
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