Re: [Geotools-devel] Parsing and encoding GML geometry metadata properties

[Andrea A. <and...@ge...>]

On Sat, Oct 2, 2010 at 6:12 PM, Justin Deoliveira <jde...@op...> wrote:
> Yeah, unfortunately this is a nasty issue. Rob has had this issue before as
> well.
> On the encoding front the plan was to instead of create a geometry not as a
> jts geometry but as a generic complex attribute. And then have the encoding
> subsystem ignore the regular geometry binding (since it is not a geometry
> object) and encode it (along with the metadta) as a generic complex
> attribute.

Wow wow, slow down a little. This seems like a nice idea but I've lost you
at the beginning of the sentence :-)

So say in the database I store something like:

<GeometryWithMetadata>
   <myMetadata>...
   <myGeometry>...
</GeometryWithMetadata>

How do I go then to turn it into a GML geometry with with metadata like:

<gml:Polygon>
   <gml:metaDataProperty>
    <gml:GenericMetaData>
     <extention>
      <area uom="m2">8476875.000000</area>
      <length uom="m">108.706000</length>
      <width uom="m">13.863100</width>
     </extention>
    </gml:GenericMetaData>
   </gml:metaDataProperty>
   <gml:exterior>
    <gml:LinearRing>
     <gml:posList>
      31.214218 43.833347  31.215328 43.833862  31.216240 43.833717 ...
     </gml:posList>
    </gml:LinearRing>
   </gml:exterior>
  </gml:Polygon>

Do you have some code skeleton I can follow?

> The parsing front is much harder as Andrea noted. What has been done in the
> past for cases like this and what I think the app-schema folks do is use the
> geometry user data as Andrea noted. But storing a map there that can store
> anything from the crs to this generic metadata. A hack to me sure but not
> sure we have much else. Unless we introduced some sort of geometry wrapper
> that stored all the metadata explicitly.
> All in all rolling your own parser is probably better for your sanity since
> the parsing story for complex features is not quite there yet when compared
> to the encoding story.

Cool

Cheers
Andrea


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Ing. Andrea Aime
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