Add write support to KML format

2014-06-25 12:17:13 +02:00
parent 8dc9618adb
commit a4e95eb513
2 changed files with 1502 additions and 0 deletions
--- a/src/ol/format/kmlformat.js
+++ b/src/ol/format/kmlformat.js
@@ -1,6 +1,7 @@
 // FIXME http://earth.google.com/kml/1.0 namespace?
 // FIXME why does node.getAttribute return an unknown type?
 // FIXME text
+// FIXME serialize arbitrary feature properties

 goog.provide('ol.format.KML');

@@ -13,12 +14,15 @@ goog.require('goog.object');
 goog.require('goog.string');
 goog.require('ol.Feature');
 goog.require('ol.array');
+goog.require('ol.color');
 goog.require('ol.feature');
 goog.require('ol.format.XMLFeature');
 goog.require('ol.format.XSD');
+goog.require('ol.geom.Geometry');
 goog.require('ol.geom.GeometryCollection');
 goog.require('ol.geom.GeometryType');
 goog.require('ol.geom.LineString');
+goog.require('ol.geom.LinearRing');
 goog.require('ol.geom.MultiLineString');
 goog.require('ol.geom.MultiPoint');
 goog.require('ol.geom.MultiPolygon');
@@ -32,6 +36,7 @@ goog.require('ol.style.IconOrigin');
 goog.require('ol.style.Image');
 goog.require('ol.style.Stroke');
 goog.require('ol.style.Style');
+goog.require('ol.style.Text');
 goog.require('ol.xml');


@@ -1641,3 +1646,889 @@ ol.format.KML.prototype.readProjectionFromDocument = function(doc) {
 ol.format.KML.prototype.readProjectionFromNode = function(node) {
  return ol.proj.get('EPSG:4326');
 };
+
+
+/**
+ * @param {Node} node Node to append a TextNode with the boolean to.
+ * @param {boolean} bool Boolean.
+ * @private
+ */
+ol.format.KML.writeBooleanTextNode_ = function(node, bool) {
+  ol.format.XSD.writeStringTextNode(node, (bool) ? '1' : '0');
+};
+
+
+/**
+ * @param {Node} node Node to append a TextNode with the color to.
+ * @param {ol.Color|string} color Color.
+ * @private
+ */
+ol.format.KML.writeColorTextNode_ = function(node, color) {
+  var rgba = ol.color.asArray(color);
+  var opacity = (rgba.length == 4) ? rgba[3] : 1;
+  var abgr = [opacity * 255, rgba[2], rgba[1], rgba[0]];
+  var i;
+  for (i = 0; i < 4; ++i) {
+    var hex = parseInt(abgr[i], 10).toString(16);
+    abgr[i] = (hex.length == 1) ? '0' + hex : hex;
+  }
+  ol.format.XSD.writeStringTextNode(node, abgr.join(''));
+};
+
+
+/**
+ * @param {Node} node Node to append a TextNode with the coordinates to.
+ * @param {Array.<number>} coordinates Coordinates.
+ * @param {Array.<*>} objectStack Object stack.
+ * @private
+ */
+ol.format.KML.writeCoordinatesTextNode_ =
+    function(node, coordinates, objectStack) {
+  var context = objectStack[objectStack.length - 1];
+  goog.asserts.assert(goog.isObject(context));
+
+  var layout = goog.object.get(context, 'layout');
+  var stride = goog.object.get(context, 'stride');
+
+  var dimension;
+  if (layout == ol.geom.GeometryLayout.XY ||
+      layout == ol.geom.GeometryLayout.XYM) {
+    dimension = 2;
+  } else if (layout == ol.geom.GeometryLayout.XYZ ||
+      layout == ol.geom.GeometryLayout.XYZM) {
+    dimension = 3;
+  } else {
+    goog.asserts.fail();
+  }
+
+  var d, i;
+  var ii = coordinates.length;
+  var text = '';
+  if (ii > 0) {
+    text += coordinates[0];
+    for (d = 1; d < dimension; ++d) {
+      text += ',' + coordinates[d];
+    }
+    for (i = stride; i < ii; i += stride) {
+      text += ' ' + coordinates[i];
+      for (d = 1; d < dimension; ++d) {
+        text += ',' + coordinates[i + d];
+      }
+    }
+  }
+  ol.format.XSD.writeStringTextNode(node, text);
+};
+
+
+/**
+ * @param {Node} node Node.
+ * @param {Array.<ol.Feature>} features Features.
+ * @param {Array.<*>} objectStack Object stack.
+ * @private
+ */
+ol.format.KML.writeDocument_ = function(node, features, objectStack) {
+  var /** @type {ol.xml.NodeStackItem} */ context = {node: node};
+  ol.xml.pushSerializeAndPop(context, ol.format.KML.DOCUMENT_SERIALIZERS_,
+      ol.format.KML.DOCUMENT_NODE_FACTORY_, features, objectStack);
+};
+
+
+/**
+ * @param {Node} node Node.
+ * @param {Object} icon Icon object.
+ * @param {Array.<*>} objectStack Object stack.
+ * @private
+ */
+ol.format.KML.writeIcon_ = function(node, icon, objectStack) {
+  var /** @type {ol.xml.NodeStackItem} */ context = {node: node};
+  var parentNode = objectStack[objectStack.length - 1].node;
+  var orderedKeys = ol.format.KML.ICON_SEQUENCE_[parentNode.namespaceURI];
+  var values = ol.xml.makeSequence(icon, orderedKeys);
+  ol.xml.pushSerializeAndPop(context,
+      ol.format.KML.ICON_SERIALIZERS_, ol.xml.OBJECT_PROPERTY_NODE_FACTORY,
+      values, objectStack, orderedKeys);
+  orderedKeys =
+      ol.format.KML.ICON_SEQUENCE_[ol.format.KML.GX_NAMESPACE_URIS_[0]];
+  values = ol.xml.makeSequence(icon, orderedKeys);
+  ol.xml.pushSerializeAndPop(context, ol.format.KML.ICON_SERIALIZERS_,
+      ol.format.KML.GX_NODE_FACTORY_, values, objectStack, orderedKeys);
+};
+
+
+/**
+ * @param {Node} node Node.
+ * @param {ol.style.Icon} style Icon style.
+ * @param {Array.<*>} objectStack Object stack.
+ * @private
+ */
+ol.format.KML.writeIconStyle_ = function(node, style, objectStack) {
+  var /** @type {ol.xml.NodeStackItem} */ context = {node: node};
+  var properties = {};
+  var src = style.getSrc();
+  var size = style.getSize();
+  var iconImageSize = style.getImageSize();
+  var iconProperties = {
+    'href': src
+  };
+
+  if (!goog.isNull(size)) {
+    goog.object.set(iconProperties, 'w', size[0]);
+    goog.object.set(iconProperties, 'h', size[1]);
+    var anchor = style.getAnchor(); // top-left
+    var origin = style.getOrigin(); // top-left
+
+    if (!goog.isNull(origin) && !goog.isNull(iconImageSize) &&
+        origin[0] !== 0 && origin[1] !== size[1]) {
+      goog.object.set(iconProperties, 'x', origin[0]);
+      goog.object.set(iconProperties, 'y',
+          iconImageSize[1] - (origin[1] + size[1]));
+    }
+
+    if (!goog.isNull(anchor) &&
+        anchor[0] !== 0 && anchor[1] !== size[1]) {
+      var /** @type {ol.format.KMLVec2_} */ hotSpot = {
+        x: anchor[0],
+        xunits: ol.style.IconAnchorUnits.PIXELS,
+        y: size[1] - anchor[1],
+        yunits: ol.style.IconAnchorUnits.PIXELS
+      };
+      goog.object.set(properties, 'hotSpot', hotSpot);
+    }
+  }
+
+  goog.object.set(properties, 'Icon', iconProperties);
+
+  var scale = style.getScale();
+  if (scale !== 1) {
+    goog.object.set(properties, 'scale', scale);
+  }
+
+  var rotation = style.getRotation();
+  if (rotation !== 0) {
+    goog.object.set(properties, 'heading', rotation); // 0-360
+  }
+
+  var parentNode = objectStack[objectStack.length - 1].node;
+  var orderedKeys = ol.format.KML.ICON_STYLE_SEQUENCE_[parentNode.namespaceURI];
+  var values = ol.xml.makeSequence(properties, orderedKeys);
+  ol.xml.pushSerializeAndPop(context, ol.format.KML.ICON_STYLE_SERIALIZERS_,
+      ol.xml.OBJECT_PROPERTY_NODE_FACTORY, values, objectStack, orderedKeys);
+};
+
+
+/**
+ * @param {Node} node Node.
+ * @param {ol.style.Text} style style.
+ * @param {Array.<*>} objectStack Object stack.
+ * @private
+ */
+ol.format.KML.writeLabelStyle_ = function(node, style, objectStack) {
+  var /** @type {ol.xml.NodeStackItem} */ context = {node: node};
+  var properties = {};
+  var fill = style.getFill();
+  if (!goog.isNull(fill)) {
+    goog.object.set(properties, 'color', fill.getColor());
+  }
+  var scale = style.getScale();
+  if (goog.isDef(scale) && scale !== 1) {
+    goog.object.set(properties, 'scale', scale);
+  }
+  var parentNode = objectStack[objectStack.length - 1].node;
+  var orderedKeys =
+      ol.format.KML.LABEL_STYLE_SEQUENCE_[parentNode.namespaceURI];
+  var values = ol.xml.makeSequence(properties, orderedKeys);
+  ol.xml.pushSerializeAndPop(context, ol.format.KML.LABEL_STYLE_SERIALIZERS_,
+      ol.xml.OBJECT_PROPERTY_NODE_FACTORY, values, objectStack, orderedKeys);
+};
+
+
+/**
+ * @param {Node} node Node.
+ * @param {ol.style.Stroke} style style.
+ * @param {Array.<*>} objectStack Object stack.
+ * @private
+ */
+ol.format.KML.writeLineStyle_ = function(node, style, objectStack) {
+  var /** @type {ol.xml.NodeStackItem} */ context = {node: node};
+  var properties = {
+    'color': style.getColor(),
+    'width': style.getWidth()
+  };
+  var parentNode = objectStack[objectStack.length - 1].node;
+  var orderedKeys = ol.format.KML.LINE_STYLE_SEQUENCE_[parentNode.namespaceURI];
+  var values = ol.xml.makeSequence(properties, orderedKeys);
+  ol.xml.pushSerializeAndPop(context, ol.format.KML.LINE_STYLE_SERIALIZERS_,
+      ol.xml.OBJECT_PROPERTY_NODE_FACTORY, values, objectStack, orderedKeys);
+};
+
+
+/**
+ * @param {Node} node Node.
+ * @param {ol.geom.Geometry} geometry Geometry.
+ * @param {Array.<*>} objectStack Object stack.
+ * @private
+ */
+ol.format.KML.writeMultiGeometry_ =
+    function(node, geometry, objectStack) {
+  goog.asserts.assert(
+      (geometry instanceof ol.geom.MultiPoint) ||
+      (geometry instanceof ol.geom.MultiLineString) ||
+      (geometry instanceof ol.geom.MultiPolygon));
+  /** @type {ol.xml.NodeStackItem} */
+  var context = {node: node};
+  var type = geometry.getType();
+  /** @type {Array.<ol.geom.Geometry>} */
+  var geometries;
+  /** @type {function(*, Array.<*>, string=): (Node|undefined)} */
+  var factory;
+  if (type == ol.geom.GeometryType.MULTI_POINT) {
+    geometries =
+        (/** @type {ol.geom.MultiPoint} */ (geometry)).getPoints();
+    factory = ol.format.KML.POINT_NODE_FACTORY_;
+  } else if (type == ol.geom.GeometryType.MULTI_LINE_STRING) {
+    geometries =
+        (/** @type {ol.geom.MultiLineString} */ (geometry)).getLineStrings();
+    factory = ol.format.KML.LINE_STRING_NODE_FACTORY_;
+  } else if (type == ol.geom.GeometryType.MULTI_POLYGON) {
+    geometries =
+        (/** @type {ol.geom.MultiPolygon} */ (geometry)).getPolygons();
+    factory = ol.format.KML.POLYGON_NODE_FACTORY_;
+  } else {
+    goog.asserts.fail();
+  }
+  ol.xml.pushSerializeAndPop(context,
+      ol.format.KML.MULTI_GEOMETRY_SERIALIZERS_, factory,
+      geometries, objectStack);
+};
+
+
+/**
+ * @param {Node} node Node.
+ * @param {ol.geom.LinearRing} linearRing Linear ring.
+ * @param {Array.<*>} objectStack Object stack.
+ * @private
+ */
+ol.format.KML.writeBoundaryIs_ = function(node, linearRing, objectStack) {
+  var /** @type {ol.xml.NodeStackItem} */ context = {node: node};
+  ol.xml.pushSerializeAndPop(context,
+      ol.format.KML.BOUNDARY_IS_SERIALIZERS_,
+      ol.format.KML.LINEAR_RING_NODE_FACTORY_, [linearRing], objectStack);
+};
+
+
+/**
+ * FIXME currently we do serialize arbitrary/custom feature properties
+ * (ExtendedData).
+ * @param {Node} node Node.
+ * @param {ol.Feature} feature Feature.
+ * @param {Array.<*>} objectStack Object stack.
+ * @private
+ */
+ol.format.KML.writePlacemark_ = function(node, feature, objectStack) {
+  var /** @type {ol.xml.NodeStackItem} */ context = {node: node};
+
+  // set id
+  if (goog.isDefAndNotNull(feature.getId())) {
+    node.setAttribute('id', feature.getId());
+  }
+
+  // serialize geometry
+  ol.xml.pushSerializeAndPop(context, ol.format.KML.PLACEMARK_SERIALIZERS_,
+      ol.format.KML.GEOMETRY_NODE_FACTORY_,
+      [feature.getGeometry()], objectStack);
+
+  // serialize properties (properties unknown to KML are not serialized)
+  var properties = feature.getProperties();
+  var styleFunction = feature.getStyleFunction();
+  if (goog.isDef(styleFunction)) {
+    // FIXME the styles returned by the style function are supposed to be
+    // resolution-independent here
+    var styles = styleFunction.call(feature, 0);
+    if (!goog.isNull(styles) && styles.length > 0) {
+      goog.object.set(properties, 'Style', styles[0]);
+      var textStyle = styles[0].getText();
+      if (!goog.isNull(textStyle)) {
+        goog.object.set(properties, 'name', textStyle.getText());
+      }
+    }
+  }
+  var parentNode = objectStack[objectStack.length - 1].node;
+  var orderedKeys = ol.format.KML.PLACEMARK_SEQUENCE_[parentNode.namespaceURI];
+  var values = ol.xml.makeSequence(properties, orderedKeys);
+  ol.xml.pushSerializeAndPop(context, ol.format.KML.PLACEMARK_SERIALIZERS_,
+      ol.xml.OBJECT_PROPERTY_NODE_FACTORY, values, objectStack, orderedKeys);
+};
+
+
+/**
+ * @param {Node} node Node.
+ * @param {ol.geom.SimpleGeometry} geometry Geometry.
+ * @param {Array.<*>} objectStack Object stack.
+ * @private
+ */
+ol.format.KML.writePrimitiveGeometry_ = function(node, geometry, objectStack) {
+  goog.asserts.assert(
+      (geometry instanceof ol.geom.Point) ||
+      (geometry instanceof ol.geom.LineString) ||
+      (geometry instanceof ol.geom.LinearRing));
+  var flatCoordinates = geometry.getFlatCoordinates();
+  var /** @type {ol.xml.NodeStackItem} */ context = {node: node};
+  goog.object.set(context, 'layout', geometry.getLayout());
+  goog.object.set(context, 'stride', geometry.getStride());
+  ol.xml.pushSerializeAndPop(context,
+      ol.format.KML.PRIMITIVE_GEOMETRY_SERIALIZERS_,
+      ol.format.KML.COORDINATES_NODE_FACTORY_,
+      [flatCoordinates], objectStack);
+};
+
+
+/**
+ * @param {Node} node Node.
+ * @param {ol.geom.Polygon} polygon Polygon.
+ * @param {Array.<*>} objectStack Object stack.
+ * @private
+ */
+ol.format.KML.writePolygon_ = function(node, polygon, objectStack) {
+  goog.asserts.assertInstanceof(polygon, ol.geom.Polygon);
+  var linearRings = polygon.getLinearRings();
+  goog.asserts.assert(linearRings.length > 0);
+  var outerRing = linearRings.shift();
+  var /** @type {ol.xml.NodeStackItem} */ context = {node: node};
+  // inner rings
+  ol.xml.pushSerializeAndPop(context,
+      ol.format.KML.POLYGON_SERIALIZERS_,
+      ol.format.KML.INNER_BOUNDARY_NODE_FACTORY_,
+      linearRings, objectStack);
+  // outer ring
+  ol.xml.pushSerializeAndPop(context,
+      ol.format.KML.POLYGON_SERIALIZERS_,
+      ol.format.KML.OUTER_BOUNDARY_NODE_FACTORY_,
+      [outerRing], objectStack);
+};
+
+
+/**
+ * @param {Node} node Node.
+ * @param {ol.style.Fill} style Style.
+ * @param {Array.<*>} objectStack Object stack.
+ * @private
+ */
+ol.format.KML.writePolyStyle_ = function(node, style, objectStack) {
+  var /** @type {ol.xml.NodeStackItem} */ context = {node: node};
+  ol.xml.pushSerializeAndPop(context, ol.format.KML.POLY_STYLE_SERIALIZERS_,
+      ol.format.KML.COLOR_NODE_FACTORY_, [style.getColor()], objectStack);
+};
+
+
+/**
+ * @param {Node} node Node to append a TextNode with the scale to.
+ * @param {number|undefined} scale Scale.
+ * @private
+ */
+ol.format.KML.writeScaleTextNode_ = function(node, scale) {
+  ol.format.XSD.writeDecimalTextNode(node, scale * scale);
+};
+
+
+/**
+ * @param {Node} node Node.
+ * @param {ol.style.Style} style Style.
+ * @param {Array.<*>} objectStack Object stack.
+ * @private
+ */
+ol.format.KML.writeStyle_ = function(node, style, objectStack) {
+  var /** @type {ol.xml.NodeStackItem} */ context = {node: node};
+  var properties = {};
+  var fillStyle = style.getFill();
+  var strokeStyle = style.getStroke();
+  var imageStyle = style.getImage();
+  var textStyle = style.getText();
+  if (!goog.isNull(imageStyle)) {
+    goog.object.set(properties, 'IconStyle', imageStyle);
+  }
+  if (!goog.isNull(textStyle)) {
+    goog.object.set(properties, 'LabelStyle', textStyle);
+  }
+  if (!goog.isNull(strokeStyle)) {
+    goog.object.set(properties, 'LineStyle', strokeStyle);
+  }
+  if (!goog.isNull(fillStyle)) {
+    goog.object.set(properties, 'PolyStyle', fillStyle);
+  }
+  var parentNode = objectStack[objectStack.length - 1].node;
+  var orderedKeys = ol.format.KML.STYLE_SEQUENCE_[parentNode.namespaceURI];
+  var values = ol.xml.makeSequence(properties, orderedKeys);
+  ol.xml.pushSerializeAndPop(context, ol.format.KML.STYLE_SERIALIZERS_,
+      ol.xml.OBJECT_PROPERTY_NODE_FACTORY, values, objectStack, orderedKeys);
+};
+
+
+/**
+ * @param {Node} node Node to append a TextNode with the Vec2 to.
+ * @param {ol.format.KMLVec2_} vec2 Vec2.
+ * @private
+ */
+ol.format.KML.writeVec2_ = function(node, vec2) {
+  node.setAttribute('x', vec2.x);
+  node.setAttribute('y', vec2.y);
+  node.setAttribute('xunits', vec2.xunits);
+  node.setAttribute('yunits', vec2.yunits);
+};
+
+
+/**
+ * @const
+ * @type {Object.<string, Array.<string>>}
+ * @private
+ */
+ol.format.KML.KML_SEQUENCE_ = ol.xml.makeStructureNS(
+    ol.format.KML.NAMESPACE_URIS_, [
+      'Document', 'Placemark'
+    ]);
+
+
+/**
+ * @const
+ * @type {Object.<string, Object.<string, ol.xml.Serializer>>}
+ * @private
+ */
+ol.format.KML.KML_SERIALIZERS_ = ol.xml.makeStructureNS(
+    ol.format.KML.NAMESPACE_URIS_, {
+      'Document': ol.xml.makeChildAppender(ol.format.KML.writeDocument_),
+      'Placemark': ol.xml.makeChildAppender(ol.format.KML.writePlacemark_)
+    });
+
+
+/**
+ * @const
+ * @type {Object.<string, Array.<string>>}
+ * @private
+ */
+ol.format.KML.DOCUMENT_SEQUENCE_ = ol.xml.makeStructureNS(
+    ol.format.KML.NAMESPACE_URIS_, [
+      'Placemark'
+    ]);
+
+
+/**
+ * @const
+ * @type {Object.<string, Object.<string, ol.xml.Serializer>>}
+ * @private
+ */
+ol.format.KML.DOCUMENT_SERIALIZERS_ = ol.xml.makeStructureNS(
+    ol.format.KML.NAMESPACE_URIS_, {
+      'Placemark': ol.xml.makeChildAppender(ol.format.KML.writePlacemark_)
+    });
+
+
+/**
+ * @const
+ * @type {Object.<string, string>}
+ * @private
+ */
+ol.format.KML.GEOMETRY_TYPE_TO_NODENAME_ = {
+  'Point': 'Point',
+  'LineString': 'LineString',
+  'LinearRing': 'LinearRing',
+  'Polygon': 'Polygon',
+  'MultiPoint': 'MultiGeometry',
+  'MultiLineString': 'MultiGeometry',
+  'MultiPolygon': 'MultiGeometry'
+};
+
+
+/**
+ * @const
+ * @type {Object.<string, Array.<string>>}
+ * @private
+ */
+ol.format.KML.ICON_SEQUENCE_ = ol.xml.makeStructureNS(
+    ol.format.KML.NAMESPACE_URIS_, [
+      'href'
+    ],
+    ol.xml.makeStructureNS(
+        ol.format.KML.GX_NAMESPACE_URIS_, [
+          'x', 'y', 'w', 'h'
+    ]));
+
+
+/**
+ * @const
+ * @type {Object.<string, Object.<string, ol.xml.Serializer>>}
+ * @private
+ */
+ol.format.KML.ICON_SERIALIZERS_ = ol.xml.makeStructureNS(
+    ol.format.KML.NAMESPACE_URIS_, {
+      'href': ol.xml.makeChildAppender(ol.format.XSD.writeStringTextNode)
+    }, ol.xml.makeStructureNS(
+        ol.format.KML.GX_NAMESPACE_URIS_, {
+          'x': ol.xml.makeChildAppender(ol.format.XSD.writeDecimalTextNode),
+          'y': ol.xml.makeChildAppender(ol.format.XSD.writeDecimalTextNode),
+          'w': ol.xml.makeChildAppender(ol.format.XSD.writeDecimalTextNode),
+          'h': ol.xml.makeChildAppender(ol.format.XSD.writeDecimalTextNode)
+        }));
+
+
+/**
+ * @const
+ * @type {Object.<string, Array.<string>>}
+ * @private
+ */
+ol.format.KML.ICON_STYLE_SEQUENCE_ = ol.xml.makeStructureNS(
+    ol.format.KML.NAMESPACE_URIS_, [
+      'Icon', 'heading', 'hotSpot', 'scale'
+    ]);
+
+
+/**
+ * @const
+ * @type {Object.<string, Object.<string, ol.xml.Serializer>>}
+ * @private
+ */
+ol.format.KML.ICON_STYLE_SERIALIZERS_ = ol.xml.makeStructureNS(
+    ol.format.KML.NAMESPACE_URIS_, {
+      'Icon': ol.xml.makeChildAppender(ol.format.KML.writeIcon_),
+      'heading': ol.xml.makeChildAppender(ol.format.XSD.writeDecimalTextNode),
+      'hotSpot': ol.xml.makeChildAppender(ol.format.KML.writeVec2_),
+      'scale': ol.xml.makeChildAppender(ol.format.KML.writeScaleTextNode_)
+    });
+
+
+/**
+ * @const
+ * @type {Object.<string, Array.<string>>}
+ * @private
+ */
+ol.format.KML.LABEL_STYLE_SEQUENCE_ = ol.xml.makeStructureNS(
+    ol.format.KML.NAMESPACE_URIS_, [
+      'color', 'scale'
+    ]);
+
+
+/**
+ * @const
+ * @type {Object.<string, Object.<string, ol.xml.Serializer>>}
+ * @private
+ */
+ol.format.KML.LABEL_STYLE_SERIALIZERS_ = ol.xml.makeStructureNS(
+    ol.format.KML.NAMESPACE_URIS_, {
+      'color': ol.xml.makeChildAppender(ol.format.KML.writeColorTextNode_),
+      'scale': ol.xml.makeChildAppender(ol.format.KML.writeScaleTextNode_)
+    });
+
+
+/**
+ * @const
+ * @type {Object.<string, Array.<string>>}
+ * @private
+ */
+ol.format.KML.LINE_STYLE_SEQUENCE_ = ol.xml.makeStructureNS(
+    ol.format.KML.NAMESPACE_URIS_, [
+      'color', 'width'
+    ]);
+
+
+/**
+ * @const
+ * @type {Object.<string, Object.<string, ol.xml.Serializer>>}
+ * @private
+ */
+ol.format.KML.LINE_STYLE_SERIALIZERS_ = ol.xml.makeStructureNS(
+    ol.format.KML.NAMESPACE_URIS_, {
+      'color': ol.xml.makeChildAppender(ol.format.KML.writeColorTextNode_),
+      'width': ol.xml.makeChildAppender(ol.format.XSD.writeDecimalTextNode)
+    });
+
+
+/**
+ * @const
+ * @type {Object.<string, Object.<string, ol.xml.Serializer>>}
+ * @private
+ */
+ol.format.KML.BOUNDARY_IS_SERIALIZERS_ = ol.xml.makeStructureNS(
+    ol.format.KML.NAMESPACE_URIS_, {
+      'LinearRing': ol.xml.makeChildAppender(
+          ol.format.KML.writePrimitiveGeometry_)
+    });
+
+
+/**
+ * @const
+ * @type {Object.<string, Object.<string, ol.xml.Serializer>>}
+ * @private
+ */
+ol.format.KML.MULTI_GEOMETRY_SERIALIZERS_ = ol.xml.makeStructureNS(
+    ol.format.KML.NAMESPACE_URIS_, {
+      'LineString': ol.xml.makeChildAppender(
+          ol.format.KML.writePrimitiveGeometry_),
+      'Point': ol.xml.makeChildAppender(
+          ol.format.KML.writePrimitiveGeometry_),
+      'Polygon': ol.xml.makeChildAppender(ol.format.KML.writePolygon_)
+    });
+
+
+/**
+ * @const
+ * @type {Object.<string, Array.<string>>}
+ * @private
+ */
+ol.format.KML.PLACEMARK_SEQUENCE_ = ol.xml.makeStructureNS(
+    ol.format.KML.NAMESPACE_URIS_, [
+      'Style', 'address', 'description', 'name', 'open',
+      'phoneNumber', 'styleUrl', 'visibility'
+    ]);
+
+
+/**
+ * @const
+ * @type {Object.<string, Object.<string, ol.xml.Serializer>>}
+ * @private
+ */
+ol.format.KML.PLACEMARK_SERIALIZERS_ = ol.xml.makeStructureNS(
+    ol.format.KML.NAMESPACE_URIS_, {
+      'MultiGeometry': ol.xml.makeChildAppender(
+          ol.format.KML.writeMultiGeometry_),
+      'LineString': ol.xml.makeChildAppender(
+          ol.format.KML.writePrimitiveGeometry_),
+      'LinearRing': ol.xml.makeChildAppender(
+          ol.format.KML.writePrimitiveGeometry_),
+      'Point': ol.xml.makeChildAppender(
+          ol.format.KML.writePrimitiveGeometry_),
+      'Polygon': ol.xml.makeChildAppender(ol.format.KML.writePolygon_),
+      'Style': ol.xml.makeChildAppender(ol.format.KML.writeStyle_),
+      'address': ol.xml.makeChildAppender(ol.format.XSD.writeStringTextNode),
+      'description': ol.xml.makeChildAppender(
+          ol.format.XSD.writeStringTextNode),
+      'name': ol.xml.makeChildAppender(ol.format.XSD.writeStringTextNode),
+      'open': ol.xml.makeChildAppender(ol.format.KML.writeBooleanTextNode_),
+      'phoneNumber': ol.xml.makeChildAppender(
+          ol.format.XSD.writeStringTextNode),
+      'styleUrl': ol.xml.makeChildAppender(ol.format.XSD.writeStringTextNode),
+      'visibility': ol.xml.makeChildAppender(
+          ol.format.KML.writeBooleanTextNode_)
+    });
+
+
+/**
+ * @const
+ * @type {Object.<string, Object.<string, ol.xml.Serializer>>}
+ * @private
+ */
+ol.format.KML.PRIMITIVE_GEOMETRY_SERIALIZERS_ = ol.xml.makeStructureNS(
+    ol.format.KML.NAMESPACE_URIS_, {
+      'coordinates': ol.xml.makeChildAppender(
+          ol.format.KML.writeCoordinatesTextNode_)
+    });
+
+
+/**
+ * @const
+ * @type {Object.<string, Object.<string, ol.xml.Serializer>>}
+ * @private
+ */
+ol.format.KML.POLYGON_SERIALIZERS_ = ol.xml.makeStructureNS(
+    ol.format.KML.NAMESPACE_URIS_, {
+      'outerBoundaryIs': ol.xml.makeChildAppender(
+          ol.format.KML.writeBoundaryIs_),
+      'innerBoundaryIs': ol.xml.makeChildAppender(
+          ol.format.KML.writeBoundaryIs_)
+    });
+
+
+/**
+ * @const
+ * @type {Object.<string, Object.<string, ol.xml.Serializer>>}
+ * @private
+ */
+ol.format.KML.POLY_STYLE_SERIALIZERS_ = ol.xml.makeStructureNS(
+    ol.format.KML.NAMESPACE_URIS_, {
+      'color': ol.xml.makeChildAppender(ol.format.KML.writeColorTextNode_)
+    });
+
+
+/**
+ * @const
+ * @type {Object.<string, Array.<string>>}
+ * @private
+ */
+ol.format.KML.STYLE_SEQUENCE_ = ol.xml.makeStructureNS(
+    ol.format.KML.NAMESPACE_URIS_, [
+      'IconStyle', 'LabelStyle', 'LineStyle', 'PolyStyle'
+    ]);
+
+
+/**
+ * @const
+ * @type {Object.<string, Object.<string, ol.xml.Serializer>>}
+ * @private
+ */
+ol.format.KML.STYLE_SERIALIZERS_ = ol.xml.makeStructureNS(
+    ol.format.KML.NAMESPACE_URIS_, {
+      'IconStyle': ol.xml.makeChildAppender(ol.format.KML.writeIconStyle_),
+      'LabelStyle': ol.xml.makeChildAppender(ol.format.KML.writeLabelStyle_),
+      'LineStyle': ol.xml.makeChildAppender(ol.format.KML.writeLineStyle_),
+      'PolyStyle': ol.xml.makeChildAppender(ol.format.KML.writePolyStyle_)
+    });
+
+
+/**
+ * @const
+ * @param {*} value Value.
+ * @param {Array.<*>} objectStack Object stack.
+ * @param {string=} opt_nodeName Node name.
+ * @return {Node|undefined} Node.
+ * @private
+ */
+ol.format.KML.GX_NODE_FACTORY_ = function(value, objectStack, opt_nodeName) {
+  return ol.xml.createElementNS(ol.format.KML.GX_NAMESPACE_URIS_[0],
+      'gx:' + opt_nodeName);
+};
+
+
+/**
+ * @const
+ * @param {*} value Value.
+ * @param {Array.<*>} objectStack Object stack.
+ * @param {string=} opt_nodeName Node name.
+ * @return {Node|undefined} Node.
+ * @private
+ */
+ol.format.KML.DOCUMENT_NODE_FACTORY_ = function(value, objectStack,
+    opt_nodeName) {
+  goog.asserts.assertInstanceof(value, ol.Feature);
+  var parentNode = objectStack[objectStack.length - 1].node;
+  goog.asserts.assert(ol.xml.isNode(parentNode));
+  return ol.xml.createElementNS(parentNode.namespaceURI, 'Placemark');
+};
+
+
+/**
+ * @const
+ * @param {*} value Value.
+ * @param {Array.<*>} objectStack Object stack.
+ * @param {string=} opt_nodeName Node name.
+ * @return {Node|undefined} Node.
+ * @private
+ */
+ol.format.KML.GEOMETRY_NODE_FACTORY_ = function(value, objectStack,
+    opt_nodeName) {
+  if (goog.isDefAndNotNull(value)) {
+    goog.asserts.assertInstanceof(value, ol.geom.Geometry);
+    var parentNode = objectStack[objectStack.length - 1].node;
+    goog.asserts.assert(ol.xml.isNode(parentNode));
+    return ol.xml.createElementNS(parentNode.namespaceURI,
+        ol.format.KML.GEOMETRY_TYPE_TO_NODENAME_[value.getType()]);
+  }
+};
+
+
+/**
+ * A factory for creating coordinates nodes.
+ * @const
+ * @type {function(*, Array.<*>, string=): (Node|undefined)}
+ * @private
+ */
+ol.format.KML.COLOR_NODE_FACTORY_ = ol.xml.makeSimpleNodeFactory('color');
+
+
+/**
+ * A factory for creating coordinates nodes.
+ * @const
+ * @type {function(*, Array.<*>, string=): (Node|undefined)}
+ * @private
+ */
+ol.format.KML.COORDINATES_NODE_FACTORY_ =
+    ol.xml.makeSimpleNodeFactory('coordinates');
+
+
+/**
+ * A factory for creating innerBoundaryIs nodes.
+ * @const
+ * @type {function(*, Array.<*>, string=): (Node|undefined)}
+ * @private
+ */
+ol.format.KML.INNER_BOUNDARY_NODE_FACTORY_ =
+    ol.xml.makeSimpleNodeFactory('innerBoundaryIs');
+
+
+/**
+ * A factory for creating Point nodes.
+ * @const
+ * @type {function(*, Array.<*>, string=): (Node|undefined)}
+ * @private
+ */
+ol.format.KML.POINT_NODE_FACTORY_ =
+    ol.xml.makeSimpleNodeFactory('Point');
+
+
+/**
+ * A factory for creating LineString nodes.
+ * @const
+ * @type {function(*, Array.<*>, string=): (Node|undefined)}
+ * @private
+ */
+ol.format.KML.LINE_STRING_NODE_FACTORY_ =
+    ol.xml.makeSimpleNodeFactory('LineString');
+
+
+/**
+ * A factory for creating LinearRing nodes.
+ * @const
+ * @type {function(*, Array.<*>, string=): (Node|undefined)}
+ * @private
+ */
+ol.format.KML.LINEAR_RING_NODE_FACTORY_ =
+    ol.xml.makeSimpleNodeFactory('LinearRing');
+
+
+/**
+ * A factory for creating Polygon nodes.
+ * @const
+ * @type {function(*, Array.<*>, string=): (Node|undefined)}
+ * @private
+ */
+ol.format.KML.POLYGON_NODE_FACTORY_ =
+    ol.xml.makeSimpleNodeFactory('Polygon');
+
+
+/**
+ * A factory for creating outerBoundaryIs nodes.
+ * @const
+ * @type {function(*, Array.<*>, string=): (Node|undefined)}
+ * @private
+ */
+ol.format.KML.OUTER_BOUNDARY_NODE_FACTORY_ =
+    ol.xml.makeSimpleNodeFactory('outerBoundaryIs');
+
+
+/**
+ * Encode an array of features in the KML format.
+ *
+ * @function
+ * @param {Array.<ol.Feature>} features Features.
+ * @return {ArrayBuffer|Node|Object|string} Result.
+ * @todo api
+ */
+ol.format.KML.prototype.writeFeatures;
+
+
+/**
+ * @inheritDoc
+ */
+ol.format.KML.prototype.writeFeaturesNode = function(features) {
+  var kml = ol.xml.createElementNS('http://earth.google.com/kml/2.2', 'kml');
+  kml.setAttributeNS('http://www.w3.org/2000/xmlns/', 'xmlns:gx',
+      ol.format.KML.GX_NAMESPACE_URIS_[0]);
+  var /** @type {ol.xml.NodeStackItem} */ context = {node: kml};
+  var properties = {};
+  if (features.length > 1) {
+    goog.object.set(properties, 'Document', features);
+  } else if (features.length == 1) {
+    goog.object.set(properties, 'Placemark', features[0]);
+  }
+  var orderedKeys = ol.format.KML.KML_SEQUENCE_[kml.namespaceURI];
+  var values = ol.xml.makeSequence(properties, orderedKeys);
+  ol.xml.pushSerializeAndPop(context, ol.format.KML.KML_SERIALIZERS_,
+      ol.xml.OBJECT_PROPERTY_NODE_FACTORY, values, [], orderedKeys);
+  return kml;
+};