Version 4 (modified by mark1, 15 years ago) (diff)

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Importing Ordnance Survey Vectors

The OS Mastermap vectors are in a GML format. To read them into most GIS systems they need to be converted first. There is a script which will convert the vectors into ESRI Shapefiles - GML2Shape.sh. This uses the ogr2ogr utility which comes with GDAL.


Procedure

To convert the OS vectors, copy them off the DVD into a directory. Then run:

GML2Shape.sh <shapefilesdir> <gmlfilesdir>

where <shapefilesdir> is a directory path where you want the shape files to go to (they will overwrite any files with the same name - suggest you use an empty directory called shapefiles in the gmlfiles directory) and <gmlfilesdir> is the directory path where the GML vectors have been copied to.

Although six vector files are created (Boundaryline, Cartographicsymbol, Cartographictext, Topographicarea, Topographicline, Topographicpoint) only the Boundaryline and Topographicline seem to contain useful information.

Once converted, copy the original DVD contents and shapefiles over to the arsf/vectors/from_os/ directory, and create a symlink (named by project code) to the shapefile directory. Also make sure the vector request table on the wiki is updated and the licence expiry date noted.