[Gdal-dev] MapInfo Text Features in OGR

[Frank Warmerdam]

On 10/31/05, Bob Cave <rlcave3rd at yahoo.com> wrote:
> Hello,
>
> I am writing a program to load and display vector
> files using OGR.  For my initial testing, I am using
> MapInfo TAB files as input.  TAB files can include a
> text feature element.  How are those represented in
> OGR?  I've noticed that the OGRFeature object
> associated with the text feature contains a point
> geometry, which makes sense as the location, but where
> is the text and other descriptive  information (font,
> alignment, etc.)?  The style string pointer is null.

Bob,

I believe that the text features and related rendering
information (font, color, etc) are returned as the
"style string" for the feature.

I don't seem to have a text file handy, but if I run
ogrinfo on a mapinfo file with point symbols I see:

OGRFeature(SampleSpeedHeading):1
  lon (Real) = -80.7188
  lat (Real) = 23.3125
  knots (Real) = 0.152118
  Heading (String) = 122
  ID (Integer) = 1
  Style = SYMBOL(a:0,c:#ff00ff,s:6pt,id:"mapinfo-sym-34.ogr-sym-4")
  POINT (-80.718800000000002 23.3125)

The "Style" line is a special sort of attribute fetched with the
OGRFeature::GetStyleString() method:
  http://www.gdal.org/ogr/classOGRFeature.html#e6ad46c5574cdc328ad029958dc976a5

The style strings should conform to the OGR Feature Style Specification.
Read over the section on the LABEL tool in the most detail.

  http://www.gdal.org/ogr/ogr_feature_style.html

Best regards,
--
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