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(mysql.info.gz) GIS class polygon

Info Catalog (mysql.info.gz) GIS class surface (mysql.info.gz) OpenGIS geometry model (mysql.info.gz) GIS class geometrycollection
 
 18.2.7 Class `Polygon'
 ----------------------
 
 A `Polygon' is a planar `Surface' representing a multisided geometry.
 It is defined by a single exterior boundary and zero or more interior
 boundaries, where each interior boundary defines a hole in the
 `Polygon'.
 
 `Polygon' Examples
 ..................
 
    * On a region map, `Polygon' objects could represent forests,
      districts, an so on.
 
 
 `Polygon' Assertions
 ....................
 
    * The boundary of a `Polygon' consists of a set of `LinearRing'
      objects (that is, `LineString' objects that are both simple and
      closed) that make up its exterior and interior boundaries.
 
    * A `Polygon' has no rings that cross. The rings in the boundary of a
      `Polygon' may intersect at a `Point', but only as a tangent.
 
    * A `Polygon' has no lines, spikes, or punctures.
 
    * A `Polygon' has an interior that is a connected point set.
 
    * A `Polygon' may have holes.  The exterior of a `Polygon' with
      holes is not connected.  Each hole defines a connected component
      of the exterior.
 
 
 The preceding assertions make a `Polygon' a simple geometry.
 
Info Catalog (mysql.info.gz) GIS class surface (mysql.info.gz) OpenGIS geometry model (mysql.info.gz) GIS class geometrycollection
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