gml:Edge represents the 1-dimensional primitive.The topological boundary of an Edge (gml:directedNode) consists of a negatively directed start Node and a positively directed end Node. The optional coboundary of an edge (gml:directedFace) is a circular sequence of directed faces which are incident on this edge in document order. In the 2D case, the orientation of the face on the left of the edge is "+"; the orientation of the face on the right on its right is "-". If provided, the aggregationType attribute shall have the value "sequence".An edge may optionally be realised by a 1-dimensional geometric primitive (gml:curveProperty).
The attribute gml:id supports provision of a handle for the XML element representing a GML Object. Its use is mandatory for all GML objects. It is of XML type ID, so is constrained to be unique in the XML document within which it occurs.
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<element name="Edge" type="gml:EdgeType" substitutionGroup="gml:AbstractTopoPrimitive"><annotation><documentation>gml:Edge represents the 1-dimensional primitive. The topological boundary of an Edge (gml:directedNode) consists of a negatively directed start Node and a positively directed end Node. The optional coboundary of an edge (gml:directedFace) is a circular sequence of directed faces which are incident on this edge in document order. In the 2D case, the orientation of the face on the left of the edge is "+"; the orientation of the face on the right on its right is "-". If provided, the aggregationType attribute shall have the value "sequence". An edge may optionally be realised by a 1-dimensional geometric primitive (gml:curveProperty).</documentation></annotation></element>