Render placemark names for points in KML format

src/ol/format/kmlformat.js

@@ -10,6 +10,8 @@ goog.require('goog.Uri');
 goog.require('goog.array');
 goog.require('goog.asserts');
 goog.require('goog.dom.NodeType');
+goog.require('goog.object');
+goog.require('goog.string');
 goog.require('ol');
 goog.require('ol.Feature');
 goog.require('ol.FeatureStyleFunction');
@@ -240,16 +242,27 @@ ol.format.KML.DEFAULT_STROKE_STYLE_ = new ol.style.Stroke({
 });
 
 
+/**
+ * @const
+ * @type {ol.style.Stroke}
+ * @private
+ */
+ol.format.KML.DEFAULT_TEXT_STROKE_STYLE_ = new ol.style.Stroke({
+  color: [51, 51, 51, 1],
+  width: 2
+});
+
+
 /**
  * @const
  * @type {ol.style.Text}
  * @private
  */
 ol.format.KML.DEFAULT_TEXT_STYLE_ = new ol.style.Text({
-  font: 'normal 16px Helvetica',
+  font: 'bold 16px Helvetica',
   fill: ol.format.KML.DEFAULT_FILL_STYLE_,
-  stroke: ol.format.KML.DEFAULT_STROKE_STYLE_,
-  scale: 1
+  stroke: ol.format.KML.DEFAULT_TEXT_STROKE_STYLE_,
+  scale: 0.8
 });
 
 
@@ -286,29 +299,109 @@ ol.format.KML.ICON_ANCHOR_UNITS_MAP_ = {
 };
 
 
+/**
+ * @param {ol.style.Style|undefined} foundStyle Style.
+ * @param {string} name Name.
+ * @return {ol.style.Style} style Style.
+ * @private
+ */
+ol.format.KML.createNameStyleFunction_ = function(foundStyle, name) {
+  /** @type {?ol.style.Text} */
+  var textStyle = null;
+  var textOffset = [0, 0];
+  var textAlign = 'start';
+  if (foundStyle.getImage()) {
+    var imageSize = foundStyle.getImage().getImageSize();
+    if (!goog.object.isEmpty(imageSize)) {
+      // Offset the label to be centered to the right of the icon, if there is
+      // one.
+      textOffset[0] = foundStyle.getImage().getScale() * imageSize[0] / 2;
+      textOffset[1] = -foundStyle.getImage().getScale() * imageSize[1] / 2;
+      textAlign = 'left';
+    }
+  }
+  if (!goog.object.isEmpty(foundStyle.getText())) {
+    textStyle = /** @type {ol.style.Text} */
+        (goog.object.clone(foundStyle.getText()));
+    textStyle.setText(name);
+    textStyle.setTextAlign(textAlign);
+    textStyle.setOffsetX(textOffset[0]);
+    textStyle.setOffsetY(textOffset[1]);
+  } else {
+    textStyle = new ol.style.Text({
+      text: name,
+      offsetX: textOffset[0],
+      offsetY: textOffset[1],
+      textAlign: textAlign
+    });
+  }
+  var nameStyle = new ol.style.Style({
+    fill: undefined,
+    image: undefined,
+    text: textStyle,
+    stroke: undefined,
+    zIndex: undefined
+  });
+  return nameStyle;
+};
+
+
 /**
  * @param {Array.<ol.style.Style>|undefined} style Style.
  * @param {string} styleUrl Style URL.
  * @param {Array.<ol.style.Style>} defaultStyle Default style.
- * @param {Object.<string, (Array.<ol.style.Style>|string)>} sharedStyles
- * Shared styles.
+ * @param {Object.<string, (Array.<ol.style.Style>|string)>} sharedStyles Shared
+ *          styles.
  * @return {ol.FeatureStyleFunction} Feature style function.
  * @private
  */
-ol.format.KML.createFeatureStyleFunction_ = function(
-    style, styleUrl, defaultStyle, sharedStyles) {
+ol.format.KML.createFeatureStyleFunction_ = function(style, styleUrl,
+    defaultStyle, sharedStyles) {
   return (
       /**
-       * @param {number} resolution Resolution.
+       * @param {number}
+       *          resolution Resolution.
        * @return {Array.<ol.style.Style>} Style.
        * @this {ol.Feature}
        */
       function(resolution) {
+        var drawName = false;
+        /** @type {ol.style.Style|undefined} */
+        var nameStyle;
+        /** @type {string} */
+        var name = '';
+        if (this.getGeometry()) {
+          drawName = (this.getGeometry().getType() ===
+                      ol.geom.GeometryType.POINT);
+        }
+
+        if (drawName) {
+          name = /** @type {string} */ (this.getProperties()['name']);
+          drawName = drawName && !goog.string.isEmptySafe(name);
+        }
+
         if (style) {
+          if (drawName) {
+            nameStyle = ol.format.KML.createNameStyleFunction_(style[0],
+                name);
+            return [style, nameStyle];
+          }
           return style;
         }
         if (styleUrl) {
-          return ol.format.KML.findStyle_(styleUrl, defaultStyle, sharedStyles);
+          var foundStyle = ol.format.KML.findStyle_(styleUrl, defaultStyle,
+              sharedStyles);
+          if (drawName) {
+            nameStyle = ol.format.KML.createNameStyleFunction_(foundStyle[0],
+                name);
+            return foundStyle.concat(nameStyle);
+          }
+          return foundStyle;
+        }
+        if (drawName) {
+          nameStyle = ol.format.KML.createNameStyleFunction_(defaultStyle[0],
+              name);
+          return defaultStyle.concat(nameStyle);
         }
         return defaultStyle;
       });