ST_IsPolygonCW — Tests if Polygons have exterior rings oriented clockwise and interior rings oriented counter-clockwise.
 boolean ST_IsPolygonCW ( geometry geom );
Returns true if all polygonal components of the input geometry use a clockwise orientation for their exterior ring, and a counter-clockwise direction for all interior rings.
Returns true if the geometry has no polygonal components.
                 
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                 Closed linestrings are not considered polygonal components, so you would still get a true return by passing a single closed linestring no matter its orientation.  | 
            
                 
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                 If a polygonal geometry does not use reversed orientation for interior rings (i.e., if one or more interior rings are oriented in the same direction as an exterior ring) then both ST_IsPolygonCW and ST_IsPolygonCCW will return false.  | 
            
Disponibilità: 2.4.0
            
 Questa funzione supporta il 3d e non distrugge gli z-index. 
            
 Questa funzione supporta le coordinate M.