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4 Geometry standards
A TIN (class GM_Tin) is a triangulated surface that uses the Delaunay algorithm
or a similar algorithm complemented with consideration for breaklines, stoplines,
and maximum length of triangle sides. The Delaunay criterion means that the circumsphere of any of the triangles must not include other points of the point set. The
Delaunay triangulation method is commonly used to produce TIN tesselations with
triangles that are optimally equiangular in shape. The length of their edges is a
minimum. Thiessen polygons are most commonly used in order to optimize the
search for the Delaunay criterion.
4.3.3.4 Operations
mbRegion
The operation "mbRegion" returns a region in the Coordinate Reference System
that contains this GM_Object. The most common use of mbRegion will be to support indexing methods that use extents other than minimum bounding rectangles
(MBR or envelopes).
Fig. 4.23. Operation mbRegion; left: minimum bounding rectangle, right: region
representativePoint
The operation "representativePoint" returns a point value (DirectPosition) that is
guaranteed to be on this GM _ Object.