grids.xsd

See ISO/DIS 19136 20.2.
An implicit description of geometry is one in which the items of the geometry do not explicitly appear in the encoding.  Instead, a compact notation records a set of parameters, and a set of objects may be generated using a rule with these parameters.  This Clause provides grid geometries that are used in the description of gridded coverages and other applications.
In GML two grid structures are defined, namely gml:Grid and gml:RectifiedGrid.