[gdal-dev] GDAL 1.7 and GML3

[Andrea Peri 2007]

Hi,

I'm use quite often the GML capability of gdal.

this is the tags I normally use and GDAL actually recognize
(these are not the only tags recognized from Gdal) :

       <gml:LineString srsName="urn:ogc:def:crs:EPSG:3003">
         <gml:posList srsDimension="2">...</gml:posList>
       </gml:LineString>

       <gml:Point srsName="urn:ogc:def:crs:EPSG:3003">
         <gml:pos srsDimension="2">1713658.01 4864821.19</gml:pos>
       </gml:Point>

       <gml:MultiPoint srsName="urn:ogc:def:crs:EPSG:3003">
         <gml:pointMember>
           <gml:Point>
             <gml:pos srsDimension="2">...</gml:pos>
           </gml:Point>
         </gml:pointMember>
       </gml:MultiPoint>

       <gml:MultiSurface srsName="urn:ogc:def:crs:EPSG:3003">
         <gml:surfaceMember>
           <gml:Polygon>
             <gml:exterior>
               <gml:LinearRing>
                 <gml:posList srsDimension="2">...</gml:posList>
               </gml:LinearRing>
             </gml:exterior>
             <gml:interior>
               <gml:LinearRing>
                 <gml:posList srsDimension="2">..</gml:posList>
               </gml:LinearRing>
             </gml:interior>
        ...
             <gml:interior>
               <gml:LinearRing>
                 <gml:posList srsDimension="2">...</gml:posList>
               </gml:LinearRing>
             </gml:interior>
           </gml:Polygon>
         </gml:surfaceMember>
       </gml:MultiSurface>

       <gml:Polygon srsName="urn:ogc:def:crs:EPSG:3003">
         <gml:exterior>
           <gml:LinearRing>
             <gml:posList srsDimension="3">...</gml:posList>
           </gml:LinearRing>
         </gml:exterior>
       </gml:Polygon>

And just today I finish to write a little patch to add the capability to 
read this
new tags (that is generated from postgis ST_AsGml() ).

       <gml:MultiCurve srsName="urn:ogc:def:crs:EPSG:3003">
         <gml:curveMember>
           <gml:Curve>
             <gml:segments>
               <gml:LineStringSegment>
                 <gml:posList srsDimension="2">...</gml:posList>
               </gml:LineStringSegment>
               <gml:LineStringSegment>
                 <gml:posList srsDimension="2">...</gml:posList>
               </gml:LineStringSegment>
             </gml:segments>
           </gml:Curve>
         </gml:curveMember>
         <gml:curveMember>
           <gml:Curve>
             <gml:segments>
               <gml:LineStringSegment>
              <gml:posList srsDimension="2">...</gml:posList>
               </gml:LineStringSegment>
             </gml:segments>
           </gml:Curve>
         </gml:curveMember>
       </gml:MultiCurve>

I will send surely this patch to Frank and Chaitanya to add to GML 
reader if it is quite good for gdal.

Regards,

Andrea Peri.

> Hi,
>
> GDAL/OGR release news says that ogr has now "Limited support for GML3".
>
> Unfortunately the documentation is limited as well, at least at
> http://gdal.org/ogr/drv_gml.html. What can ogr do now with gml3?  What 
> interests
> me most is that how well it can interpret gml3 that comes out from WFS 
> 1.1.0
> servers.
>
> -Jukka Rahkonen-