ST_OptimalAlphaShape — Computes an Alpha-shape enclosing a geometry using an "optimal" alpha value.


geometry ST_OptimalAlphaShape(geometry geom, boolean allow_holes = false, integer nb_components = 1);



ST_OptimalAlphaShape is deprecated as of 3.5.0. Use CG_OptimalAlphaShape instead.

Computes the "optimal" alpha-shape of the points in a geometry. The alpha-shape is computed using a value of α chosen so that:

  1. the number of polygon elements is equal to or smaller than nb_components (which defaults to 1)

  2. all input points are contained in the shape

The result will not contain holes unless the optional allow_holes argument is specified as true.

Availability: 3.3.0 - requires SFCGAL >= 1.4.1.

Questo metodo richiede il backend SFCGAL.