<?xml version="1.0" encoding="UTF-8"?>
<schema targetNamespace="http://www.opengis.net/gml" xmlns:gml="http://www.opengis.net/gml" xmlns="http://www.w3.org/2001/XMLSchema" xmlns:xlink="http://www.w3.org/1999/xlink" elementFormDefault="qualified" version="3.0.1">
  <annotation>
    <appinfo source="urn:opengis:specification:gml:schema-xsd:grids:v3.0.1">grids.xsd</appinfo>
    <documentation xml:lang="en">Grid geometries
    A subset of implicit geometries
    Designed for use with GML Coverage schema, but maybe useful elsewhere as well.  
    
    Copyright (c) 2002 OGC, All Rights Reserved.
    </documentation>
  </annotation>
  <!-- ==============================================================
       includes and imports
	============================================================== -->
  <include schemaLocation="geometryBasic0d1d.xsd"/>
  <!-- ==============================================================
       global elements
	============================================================== -->
  <element name="_ImplicitGeometry" type="gml:AbstractGeometryType" abstract="true" substitutionGroup="gml:_Geometry"/>
  <!-- =========================================================== -->
  <element name="Grid" type="gml:GridType" substitutionGroup="gml:_ImplicitGeometry"/>
  <!-- =========================================================== -->
  <complexType name="GridType">
    <annotation>
      <documentation>Implicitly defines an unrectified grid, which is a network composed of two or more sets of equally spaced parallel lines in which the members of each set intersect the members of the other sets at right angles.</documentation>
    </annotation>
    <complexContent>
      <extension base="gml:AbstractGeometryType">
        <sequence>
          <element name="limits" type="gml:GridLimitsType"/>
          <element name="axisName" type="string" maxOccurs="unbounded"/>
        </sequence>
        <attribute name="dimension" type="positiveInteger" use="required"/>
      </extension>
    </complexContent>
  </complexType>
  <!-- =========================================================== -->
  <complexType name="GridLimitsType">
    <sequence>
      <element name="GridEnvelope" type="gml:GridEnvelopeType"/>
    </sequence>
  </complexType>
  <!-- =========================================================== -->
  <complexType name="GridEnvelopeType">
    <annotation>
      <documentation>Provides grid coordinate values for the diametrically opposed corners of an envelope that bounds a section of grid. The value of a single coordinate is the number of offsets from the origin of the grid in the direction of a specific axis.</documentation>
    </annotation>
    <sequence>
      <element name="low" type="gml:integerList"/>
      <element name="high" type="gml:integerList"/>
    </sequence>
  </complexType>
  <!-- =========================================================== -->
  <element name="RectifiedGrid" type="gml:RectifiedGridType" substitutionGroup="gml:Grid"/>
  <!-- =========================================================== -->
  <complexType name="RectifiedGridType">
    <annotation>
      <documentation>A rectified grid has an origin and vectors that define its post locations.</documentation>
    </annotation>
    <complexContent>
      <extension base="gml:GridType">
        <sequence>
          <element name="origin" type="gml:PointPropertyType"/>
          <element name="offsetVector" type="gml:VectorType" maxOccurs="unbounded"/>
        </sequence>
      </extension>
    </complexContent>
  </complexType>
  <!-- =========================================================== -->
</schema>