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I want to reverse the line direction for all lines in a shapefile from the Linux commandline (that is to say, using a script). Currently I'm using the SwapVectorDirection QGIS plugin which works well but has to be run manually. Ideally I'd like a solution using ogr since I have it installed on my system.

This question is similar but I'm looking specifically for something I can include in a Linux script.

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Use the ogr2ogr utility with the ST_REVERSE function in a SQL statement and OGR SQLite dialect:

For example:

ogr2ogr -dialect SQLITE -sql "select st_reverse(GEOMETRY), * from input" output.shp input.shp

Note: You need to pass in the st_reverse(GEOMETRY) first as the GEOMETRY field is automatically selected if the * wildcard is used and ogr will write only the first geometry out to a single geometry type layer.

  • Snap, I just figured that out, see edit. – user2856 Jan 23 at 1:52
  • Thanks, that works a treat. The only tweak I had to make was to swap the columns in the query to be st_reverse(GEOMETRY), *; without this I wasn't seeing any reversal. BTW, with the aforementioned caveat the pre-edit version using * worked just fine with ogr2ogr from GDAL 2.2.3. Presumably by putting the function first it overrode the default GEOMETRY column. I'll accept this answer in 24 hours unless a much better answer shows up. – Alex Hajnal Jan 23 at 1:52
  • Do you know if there's a list of all the supported spacial functions? I took on the GDAL site and didn't see one. – Alex Hajnal Jan 23 at 2:08
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    Depends on the implementation and data source, but the OGC Simple Feature Access - Part 2: SQL Option standard is the place to start – user2856 Jan 23 at 2:28
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    SQL dialect SQLite is using the spatial functions from SpatiaLite gaia-gis.it/gaia-sins/spatialite-sql-latest.html. – user30184 Jan 23 at 8:42

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