PostGIS
Name
GetRingEdges — Returns the ordered set of signed edge identifiers met by walking on an a given edge side.
Synopsis
getfaceedges_returntype +`*`+GetRingEdges*(`varchar
`atopology, integer aring, integer max_edges=null`)`;
Description
Returns the ordered set of signed edge identifiers met by walking on an a given edge side. Each output consists of a sequence and a signed edge id. Sequence numbers start with value 1.
If you pass a positive edge id, the walk starts on the left side of the corresponding edge and follows the edge direction. If you pass a negative edge id, the walk starts on the right side of it and goes backward.
If max_edges is not null no more than those records are returned by
that function. This is meant to be a safety parameter when dealing with
possibly invalid topologies.
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Availability: 2.0.0