[GRASS-user] ps.map character encoding problems

[Frank Broniewski]

On Monday 12 November 2007 17:29:07 Glynn Clements wrote:
> Frank Broniewski wrote:
> > I have trouble with the ps.map module and character encoding in the
> > legend. I have french characters (é,è and others) as a layer label. The
> > layer itself was imported from a postgis database, which has a unicode
> > encoding. As far as I understand the manual for ps.map, you need your
> > mapping instructions file encoded to ISO-8859-1. At the end of the manual
> > is the appropriate command listed. so far so good.
> > But I use a condition for my vector layer, which has the layer name as
> > where clause term. Converting my mapping instructions file to ISO-8859-1
> > gives me another error, with the result that the layer cannot be drawn
> > and ps.map exits. Here's the error:
> >
> > ps.map -e input=print.txt output=print.ps
> > PS-PAINT: scale set to 1 : 360512.
> > PS-PAINT: reading raster file <dgm in PERMANENT> ...
> > PS-PAINT: reading vector points file <sites in PERMANENT>
> > ...DBMI-Postgres driver error:
> > Cannot select:
> > SELECT id FROM sites WHERE epoch = 'M�solithique'
> > ERROR:  invalid byte sequence for encoding "UTF8": 0xe9736f
> > HINT:  This error can also happen if the byte sequence does not match the
> > encoding expected by the server, which is controlled by
> > "client_encoding".
> >
> > Any help is greatly appreciated
>
> ps.map itself doesn't care about encodings; it's all just bytes.
>
> Any text which is meant to appear in the output is embedded verbatim
> in the PostScript file. The prolog automatically re-encodes any fonts
> to ISOLatin1Encoding (PostScript's default encoding isn't much use, as
> nothing other than PostScript uses it), so any text needs to use that
> encoding.
>
> Similarly, any strings which are passed to library functions etc are
> passed without any conversions.
>
> In this particular case, it should suffice to use ISO-8859-1 for
> displayed text and UTF-8 for the WHERE clause. The reference to
> client_encoding suggests that it may be possible for the DBMS to
> perform encoding conversions, but I don't know how, or if it's even
> possible from GRASS.
>
> It would theoretically be possible to modify ps.map to convert
> displayed text from a user-defined encoding to ISO-8859-1. However,
> this could require a significant amount of work. As ps.map will be
> superseded in 7.x, I'm not sure that it's worth the effort.

Hi Glynn,

I must admit, I didn't understand fully what your post was up to. But! it 
helped me to sort my problem somehow. You mentioned, that text is "embedded 
verbatim in the PostScript file.". Well, so I opened my postscript file in my 
editor, changed the encoding to ISO-8859-1 and replaced the character garbage 
with my desired ones. Et Voila, here it works now.
Many thanks to you.

You mentioned, ps.map will be superseded in the future, but what will the 
replacement be? I just ask, because today I had lots of trouble getting my  
GIS data printed in a good quality with all the elements a map needs; 
legends, north arrows and scalebars and such. I tried QGIS, but there is an 
export error in relation to QT making labels and lines oversized. And there 
are more problems concerning classification of data. I tried uDig, but I 
really don't understand the workflow there and customizing is so xml'ish. So 
I remembered my days at university where we were working with the Arcinfo 
equivalent of ps.map, whatever it name was, don't remember anymore. ps.map 
just made my day today.

Well, thanks again for your tipps.

Frank