[Gdal-dev] OGR dataset default feature style

[Frank Warmerdam]

julien demaria wrote:
> Hi,
> 
> 
> OGR - Feature Style Specifications :
> 
> "There are actually 2 levels at which style information can be found: 
> 
> At the dataset level:
>   - A dataset can have a default style that applies to all features. 
>   - It can also have a table of pre-defined styles that can then be referred to 
>     by the layers or by the individual features. 
>     The mechanism for that is defined further down in this document.
> ..."
> 
> Is dataset default style implemented in OGR ?
> 
> I understand in specifications that this informations are stored in the 
 > "Styles Table Format" which is stored in an external .ofs file for formats
 > that don't support styles table. I want use "ESRI Shapefile" driver, are
 >.ofs file implemented for it ?
> 
> Does the dataset default style mechanism allow "styles union" ? For example 
 >if we define a global color at the dataset level : PEN(c:#ff0000), can we suppose
 > that a local feature with only width : PEN(w:5) inherit from global color ?
 >( ===> PEN(c:#ff0000,w:5) )

Julien,

To the best of my knowledge none of the "default at the layer" part of the
spec has been implemented - at least not in the format drivers.  There might
be style information in the OGRLayer object.

Likewise OpenEV does not currently look for OGRFS style information at the
layer level when reading.

However, that doesn't mean we couldn't work towards this design ... just that
not much of this aspect exists in code now.

Best regards,
-- 
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