[Gdal-dev] Re: [Openev-discuss] OGR feature styles question

[Frank Warmerdam]

Gillian Walter wrote:
> Hi,
> 
> The following (quite old) part of the gdal website mentions ogr feature 
> style files (.OFS) under section 2.7:
> 
> http://gdal.velocet.ca/~warmerda/projects/opengis/ogr_feature_style_008.html 
> 
> 
> Has support for these files actually been implemented anywhere?  If so, 
> did it follow this spec, or was something different done?  I am looking 
> at saving layer display properties, and I'm not sure whether to make 
> this support completely internal to our applications, or to try to do 
> something that could also be used in OpenEV.

Gillian,

The advanced OpenEV rendering capabilities are implemented according to the
OGR Feature Style document though it is by no means a complete implementation
of the specification.   However, within OpenEV the feature style strings
are stored in a _gv_ogrfs attribute on the features.  The OGR reader takes
care of reading the feature style from an OGRFeature and turning it into an
_gv_ogrfs attribute.

There isn't really much capability in OGR or OpenEV for saving the _gv_ogrfs
stuff in arbitrary output files.  Ideally the shapefile saver would add a
column for it if it is present in the dataset but that has no been done.  The
project saved logic *does* preserve the _gv_ogrfs.

My suggestion is to save the feature style as a regular attribute called
_gv_ogrfs for your application purposes.

Best regards,
-- 
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I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
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