Alias

DelaunayTriangles

Description

Returns polygons that represent Delaunay Trianglulations from collections of points.

The union of all simplices in the triangulation is the convex hull of the points.

	This method supports GeometryCollections

Coordinate Dimensions

2D	3D	M

Spatial Standards Support

Examples

SELECT ST_AsText(
ST_DelaunayTriangles(ST_GeomFromText(
'GEOMETRYCOLLECTION (MULTIPOINT ((2 2), (3 4), (4 2), (2 1)),
                     LINESTRING (5 4, 6 2, 4 3, 3 2, 4 1),
                     POLYGON ((5 5, 5 6, 7 6, 7 5, 5 5)))')));

--Result
GEOMETRYCOLLECTION (POLYGON ((2 2, 2 1, 3 2, 2 2)),
POLYGON ((2 2, 3 2, 3 4, 2 2)),
POLYGON ((3 4, 3 2, 4 3, 3 4)),
POLYGON ((3 4, 4 3, 5 4, 3 4)),
POLYGON ((3 4, 5 4, 5 5, 3 4)),
POLYGON ((3 4, 5 5, 5 6, 3 4)),
POLYGON ((5 6, 5 5, 7 5, 5 6)),
POLYGON ((5 6, 7 5, 7 6, 5 6)),
POLYGON ((4 1, 6 2, 4 2, 4 1)),
POLYGON ((4 1, 4 2, 3 2, 4 1)),
POLYGON ((4 1, 3 2, 2 1, 4 1)),
POLYGON ((3 2, 4 2, 4 3, 3 2)),
POLYGON ((4 3, 4 2, 6 2, 4 3)),
POLYGON ((4 3, 6 2, 5 4, 4 3)),
POLYGON ((5 4, 6 2, 7 5, 5 4)),
POLYGON ((5 4, 7 5, 5 5, 5 4)))

GeomA

ST_DelaunayTriangles (geomA)

Related functions

ST_ConvexHull