[postgis-devel] update topology locally

[Sandro Santilli]

On Wed, Feb 11, 2015 at 11:15:26AM +0100, Rémi Cura wrote:
> Hey everybody (and most probably Sandro),
> 
> Work on trigger is going on.
> 
> I end up with a corrupted topology (by design):
> I have list of nodes that have changed ,
> association with edges has been updated and is correct (start_node,
> end_node).
> 
> Now I would like a function to correct next_lft, next_right, and face only
> for the edge associated with my list of nodes.
> 
> Do you know if I can scavenge it somewhere?

I've been actually thinking for some time that we'd need such a function.
Right now the code computing that (which I call "edge linking") is buried
into the ST_AddEdgeModFace and ST_AddEdgeNewFaces functions.

The primitive block of such function could be GetNodeEdges:
http://postgis.net/docs/manual-dev/GetNodeEdges.html
That function does not make use of "edge linking" fields.

--strk;

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