[mapserver-users] Using OGR with a TILEINDEX layer

[Frank Warmerdam]

Brent Fraser wrote:
> I used ogrtindex to create a tileindex shapefile with absolute paths but 
> get an error in mapserver v5.6.1 when attempting to use it:
> 
> msDrawMap(): Image handling error. Failed to draw layer named 
> 'LINE'.
> msOGRFileOpen(): OGR error. Open failed for OGR connection in layer 
> `LINE'.  File not found or unsupported format
> 
>   LAYER
>     NAME "index_west"
>     TYPE TILEINDEX
>     DATA "G:\GeoData\1_250k\Alberta\AltaLIS\250k_west.shp"
>   END
> 
> 
>   LAYER # LINE
>     NAME 'LINE'
>     STATUS on
>     TYPE LINE
>     TILEINDEX "index_west"
>     CONNECTIONTYPE OGR
> #    CONNECTION 'G:\GeoData\1_250k\Alberta\AltaLIS\82opos.dgn' # entities'
> 
>     INCLUDE "AltaLIS_250k_render_inc.map"
>   END
> 
> Does OGR work when referencing a TILEINDEX?

Brent,

I don't have an authoritative answer, but a brief skim of mapogr.cpp seems
to suggest that it only supports tileindexes in OGR supported formats and
not in a separate layer.  So, the answer seems to be no, though you should
be able to just specify the 250k_west.shp file directly as your tileindex
in the main OGR layer.

It would be desirable to rework mapogr.cpp to support the current more
general concept of tileindexes but it might be a non-trivial amount of work
and significant care would be required to avoid backward compatibility
problems.

Best regards,
-- 
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I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
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