///<summary> /// Returns the boundary, or the empty geometry if this Geometry is empty. ///</summary> ///<remarks>For a discussion /// of this function, see the OpenGIS Simple Features Specification. As stated in SFS /// Section 2.1.13.1, "the boundary of a Geometry is a set of Geometries of the next lower dimension."</remarks> ///<returns>Returns the closure of the combinatorial boundary of this Geometry.</returns> public override Geometry GetBoundary() { if ( IsEmpty() ) { return _geometryFactory.CreateGeometryCollection( null ); } GeometryGraph g = new GeometryGraph(0, this); Coordinates pts = g.GetBoundaryPoints(); return _geometryFactory.CreateMultiPoint(pts); }