[gdal-dev] change icon of placemark of a kml file

[Even Rouault]

Le mercredi 09 septembre 2015 04:48:13, Cheng Tang a écrit :
> Hi Gdal Developers:
> 
> I have a question: Can I change icon of placemark of a kml file through
> code using ogr python? I did not find this function in ogr document.

Tang,

you need to use the LIBML driver of GDAL (not necessarily available in all 
builds) : http://gdal.org/drv_libkml.html

You need to attach a style to the OGR feature. The OGR Feature Style 
specification is describe here : http://gdal.org/ogr_feature_style.html .

For example :
feat.SetStyleString('SYMBOL(id:"http://gdal.org/gdalicon.png")')


Little demo without code :

Given test.csv with the following content :

id,WKT,OGR_STYLE
1,"POINT(2 49)","SYMBOL(id:""http://gdal.org/gdalicon.png"")"

"ogr2ogr -f libkml out.kml test.csv -select id" generates :

<?xml version="1.0" encoding="UTF-8"?>
<kml xmlns="http://www.opengis.net/kml/2.2">
  <Document id="root_doc">
    <Schema id="test.schema">
      <SimpleField name="id" type="string"/>
    </Schema>
    <Document id="test">
      <name>test</name>
      <Placemark id="test.1">
        <Style>
          <IconStyle>
            <Icon>
              <href>http://gdal.org/gdalicon.png</href>
            </Icon>
          </IconStyle>
        </Style>
        <ExtendedData>
          <SchemaData schemaUrl="#test.schema">
            <SimpleData name="id">1</SimpleData>
          </SchemaData>
        </ExtendedData>
        <Point>
          <coordinates>
            2,49,0
          </coordinates>
        </Point>
      </Placemark>
    </Document>
  </Document>
</kml>

If you want to see a OGR Python script that explores most possibilities of 
KML, you can have a look at 
https://svn.osgeo.org/gdal/trunk/autotest/kml_generate_test_files.py . But the 
above should be sufficient for your immediate needs.

Even

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