[gdal-dev] Geospatial PDF with OGR_DATASOURCE

[Rahkonen Jukka]

Even Rouault wrote:
> 
> Le samedi 02 juin 2012 12:36:39, Jukka Rahkonen a écrit :
> > Hi,
> > 
> > I was reading about a possibility of adding OGR vector 
> layers on top of
> > raster layer in geospatial pdf from http://gdal.org/frmt_pdf.html
> > 
> > Are there any example commands available? I guess that at 
> least discovering
> > the use of OGR_DISPLAY_FIELD and OGR_DISPLAY_LAYER_NAMES 
> may take a while
> > with plain trial and error.
> 
> I've tried to make the description of those option hopefully 
> a bit clearer. 
> Have a look at http://trac.osgeo.org/gdal/changeset/24529 . 
> If you can help in 
> making this more understandable, you're welcome. I know I'm 
> not so good at 
> writing docs.
> 
> Without screenshots of the UI of the "well-know PDF viewer" 
> (but GDAL/OGR doc 
> is generally rather ascetic ;-)), I'm afraid that it is still 
> a bit difficult to 
> understand. The best is to experiment.


I made some quick trials by combining some raster base maps and 
shapefiles and I am sure that this will be an amusing toy. But
with the default settings the vector features are almost invisible
on the map because of the drawing styles. I made a blind
trial with OGR Feature Styles and wrote these two lines into a
.ofs file for making linework a bit wider
	OFS-version 1.0
	DefaultStyle: PEN(c:#FF0000,w:5px)

However, it did not make any difference. Perhaps OFS is not
supported yet, or?  I did notice that I can change the colour
of the features through Acrobat reader's UI, but I cannot set
the line width. As a first aid I would suggest to use wider 
lines and bigger points as defaults. Areas, which are drawn 
as semi-transparent with a light grey fill are OK.

I am eager to have a possibility to capture a base map from
WMS and some vectors from WFS, put some styles into the 
vectors and combine everything together with gdal_translate 
into a geospatial PDF. It does not seem to be so far away.

-Jukka Rahkonen-