spatialite-network

[Stephen Knox]

Hi All,

I have been trying to use spatialite to do some routing at work. We
use ArcGIS, but without Network Analyst. I am using an Ordnance Survey
dataset which ought to be good quality, however there are still a
number of topological errors that need to be corrected.

My workflow so far has been:

- import the shapefile into spatialite
- create a new LINESTRING geometry column and somehow convert the
MULTILINESTRING output into LINESTRING
- run spatialite-network on the shapefile
- get a topology error
- find and correct it in ArcGIS
- regenerate the corrected shapefile
- reimport into spatialite
- repeat ad nauseam

This is clearly time consuming for a number of errors. I tried to
correct things within spatialite-gui, but I think I fell foul of the
precision issue mentioned on this list before:http://groups.google.com/
group/spatialite-users/browse_thread/thread/e1d5c48de1fae72f?hl=en

Are there any other workflows people use? I was considering importing
the nodes as a separate points layer and just generating lines between
each node, whilst retaining each link attribute.

The other thing I was thinking was how easy it would be to change
spatialite-network so it reported all errors in a shapefile, rather
than one at a time, then all the errors could be corrected, which
would save regenerating the shapefile each time.

Stephen Knox