A Polygon is a special surface that is defined by a single surface patch (seeD.3.6). The boundary of this patch is coplanar and the polygon uses planar interpolation inits interior. The elements exterior and interior describe the surface boundary of thepolygon.
Database handle for the object. It is of XML type ID, so is constrained to beunique in the XML document within which it occurs. An external identifier for the object inthe form of a URI may be constructed using standard XML and XPointer methods. This is doneby concatenating the URI for the document, a fragment separator, and the value of the idattribute.
<element name="Polygon" type="gml:PolygonType" substitutionGroup="gml:AbstractSurface"><annotation><documentation>A Polygon is a special surface that is defined by a single surface patch (see D.3.6). The boundary of this patch is coplanar and the polygon uses planar interpolation in its interior. The elements exterior and interior describe the surface boundary of the polygon.</documentation></annotation></element>