Serialize polygon as surface

src/objectliterals.jsdoc

@@ -309,6 +309,9 @@
  * @property {string} featureNS Feature namespace.
  * @property {string} featureType Feature type to parse.
  * @property {string} srsName srsName to use when writing geometries.
+ * @property {boolean|undefined} surface Write gml:Surface instead of
+ *     gml:Polygon elements. This also affects the elements in multi-part
+ *     geometries. Default is `false´.
  */
 
 /**

src/ol/format/gmlformat.js

@@ -52,6 +52,13 @@ ol.format.GML = function(opt_options) {
    */
   this.srsName_ = options.srsName;
 
+  /**
+   * @private
+   * @type {boolean}
+   */
+  this.surface_ = goog.isDef(options.surface) ?
+      options.surface : false;
+
   goog.base(this);
 };
 goog.inherits(ol.format.GML, ol.format.XMLFeature);
@@ -1165,6 +1172,26 @@ ol.format.GML.writePolygon_ = function(node, geometry, objectStack) {
 };
 
 
+/**
+ * @param {Node} node Node.
+ * @param {ol.geom.Polygon} geometry Polygon geometry.
+ * @param {Array.<*>} objectStack Node stack.
+ * @private
+ */
+ol.format.GML.writeSurface_ = function(node, geometry, objectStack) {
+  var context = objectStack[objectStack.length - 1];
+  goog.asserts.assert(goog.isObject(context));
+  var srsName = goog.object.get(context, 'srsName');
+  if (goog.isDefAndNotNull(srsName)) {
+    node.setAttribute('srsName', srsName);
+  }
+  ol.xml.pushSerializeAndPop({node: node, srsName: srsName},
+      ol.format.GML.PATCH_SERIALIZERS_,
+      ol.xml.makeSimpleNodeFactory('patches'), [geometry],
+      objectStack);
+};
+
+
 /**
  * @param {Node} node Node.
  * @param {ol.geom.MultiPolygon} geometry MultiPolygon geometry.
@@ -1224,6 +1251,23 @@ ol.format.GML.writeSurfaceMember_ = function(node, polygon, objectStack) {
 };
 
 
+/**
+ * @param {Node} node Node.
+ * @param {ol.geom.Polygon} polygon Polygon geometry.
+ * @param {Array.<*>} objectStack Node stack.
+ * @private
+ */
+ol.format.GML.writeSurfacePatches_ = function(node, polygon, objectStack) {
+  var context = objectStack[objectStack.length - 1];
+  goog.asserts.assert(goog.isObject(context));
+  var srsName = goog.object.get(context, 'srsName');
+  ol.xml.pushSerializeAndPop(/** @type {ol.xml.NodeStackItem} */
+      ({node: node, srsName: srsName, writeSrsName: false}),
+      ol.format.GML.SURFACE_SERIALIZERS_,
+      ol.xml.makeSimpleNodeFactory('PolygonPatch'), [polygon], []);
+};
+
+
 /**
  * @type {Object.<string, Object.<string, ol.xml.Serializer>>}
  * @private
@@ -1235,6 +1279,17 @@ ol.format.GML.SURFACEMEMBER_SERIALIZERS_ = {
 };
 
 
+/**
+ * @type {Object.<string, Object.<string, ol.xml.Serializer>>}
+ * @private
+ */
+ol.format.GML.PATCH_SERIALIZERS_ = {
+  'http://www.opengis.net/gml': {
+    'patches': ol.xml.makeChildAppender(ol.format.GML.writeSurfacePatches_)
+  }
+};
+
+
 /**
  * @type {Object.<string, Object.<string, ol.xml.Serializer>>}
  * @private
@@ -1247,6 +1302,17 @@ ol.format.GML.RING_SERIALIZERS_ = {
 };
 
 
+/**
+ * @type {Object.<string, Object.<string, ol.xml.Serializer>>}
+ * @private
+ */
+ol.format.GML.SURFACE_SERIALIZERS_ = {
+  'http://www.opengis.net/gml': {
+    'PolygonPatch': ol.xml.makeChildAppender(ol.format.GML.writePolygon_)
+  }
+};
+
+
 /**
  * @type {Object.<string, Object.<string, ol.xml.Serializer>>}
  * @private
@@ -1257,6 +1323,7 @@ ol.format.GML.GEOMETRY_SERIALIZERS_ = {
     'LineString': ol.xml.makeChildAppender(ol.format.GML.writeLineString_),
     'LinearRing': ol.xml.makeChildAppender(ol.format.GML.writeLinearRing_),
     'Polygon': ol.xml.makeChildAppender(ol.format.GML.writePolygon_),
+    'Surface': ol.xml.makeChildAppender(ol.format.GML.writeSurface_),
     'MultiSurface': ol.xml.makeChildAppender(ol.format.GML.writeMultiSurface_)
   }
 };
@@ -1272,6 +1339,9 @@ ol.format.GML.GEOMETRY_SERIALIZERS_ = {
  */
 ol.format.GML.GEOMETRY_NODE_FACTORY_ = function(value, objectStack,
     opt_nodeName) {
+  var context = objectStack[objectStack.length - 1];
+  goog.asserts.assert(goog.isObject(context));
+  var surface = goog.object.get(context, 'surface');
   goog.asserts.assertInstanceof(value, ol.geom.Geometry);
   var parentNode = objectStack[objectStack.length - 1].node;
   goog.asserts.assert(ol.xml.isNode(parentNode));
@@ -1279,6 +1349,9 @@ ol.format.GML.GEOMETRY_NODE_FACTORY_ = function(value, objectStack,
   if (nodeName === 'MultiPolygon') {
     nodeName = 'MultiSurface';
   }
+  if (nodeName === 'Polygon' && surface === true) {
+    nodeName = 'Surface';
+  }
   return ol.xml.createElementNS(parentNode.namespaceURI,
       nodeName);
 };
@@ -1289,7 +1362,7 @@ ol.format.GML.GEOMETRY_NODE_FACTORY_ = function(value, objectStack,
  */
 ol.format.GML.prototype.writeGeometryNode = function(geometry) {
   var geom = ol.xml.createElementNS('http://www.opengis.net/gml', 'geom');
-  var context = {node: geom, srsName: this.srsName_};
+  var context = {node: geom, srsName: this.srsName_, surface: this.surface_};
   ol.xml.pushSerializeAndPop(/** @type {ol.xml.NodeStackItem} */
       (context), ol.format.GML.GEOMETRY_SERIALIZERS_,
       ol.format.GML.GEOMETRY_NODE_FACTORY_, [geometry], []);

test/spec/ol/format/gmlformat.test.js

@@ -179,12 +179,12 @@ describe('ol.format.GML', function() {
 
     describe('surface', function() {
 
-      it('can read a surface geometry', function() {
+      it('can read and write a surface geometry', function() {
         var text =
             '<gml:Surface xmlns:gml="http://www.opengis.net/gml" ' +
             '    srsName="CRS:84">' +
             '  <gml:patches>' +
-            '    <gml:PolygonPatch interpolation="planar">' +
+            '    <gml:PolygonPatch>' +
             '      <gml:exterior>' +
             '        <gml:LinearRing>' +
             '          <gml:posList>1 2 3 2 3 4 1 2</gml:posList>' +
@@ -208,6 +208,9 @@ describe('ol.format.GML', function() {
         expect(g.getCoordinates()).to.eql([[[1, 2, 0], [3, 2, 0], [3, 4, 0],
                 [1, 2, 0]], [[2, 3, 0], [2, 5, 0], [4, 5, 0], [2, 3, 0]],
               [[3, 4, 0], [3, 6, 0], [5, 6, 0], [3, 4, 0]]]);
+        format = new ol.format.GML({srsName: 'CRS:84', surface: true});
+        var serialized = format.writeGeometry(g);
+        expect(serialized.firstElementChild).to.xmleql(ol.xml.load(text));
       });
 
     });
@@ -573,7 +576,7 @@ describe('ol.format.GML', function() {
             '  <gml:surfaceMember>' +
             '    <gml:Surface>' +
             '      <gml:patches>' +
-            '        <gml:PolygonPatch interpolation="planar">' +
+            '        <gml:PolygonPatch>' +
             '          <gml:exterior>' +
             '            <gml:LinearRing>' +
             '              <gml:posList>1 2 3 2 3 4 1 2</gml:posList>' +
@@ -596,7 +599,7 @@ describe('ol.format.GML', function() {
             '  <gml:surfaceMember>' +
             '    <gml:Surface>' +
             '      <gml:patches>' +
-            '        <gml:PolygonPatch interpolation="planar">' +
+            '        <gml:PolygonPatch>' +
             '          <gml:exterior>' +
             '            <gml:LinearRing>' +
             '              <gml:posList>1 2 3 2 3 4 1 2</gml:posList>' +