Add ol.layer.Heatmap#blur getter and setter

src/ol/layer/heatmaplayer.js

@@ -16,6 +16,7 @@ goog.require('ol.style.Style');
  * @enum {string}
  */
 ol.layer.HeatmapLayerProperty = {
+  BLUR: 'blur',
   GRADIENT: 'gradient',
   RADIUS: 'radius'
 };
@@ -53,12 +54,6 @@ ol.layer.Heatmap = function(opt_options) {
    */
   this.gradient_ = null;
 
-  /**
-   * @private
-   * @type {number}
-   */
-  this.blur_ = goog.isDef(options.blur) ? options.blur : 15;
-
   /**
    * @private
    * @type {number}
@@ -81,9 +76,12 @@ ol.layer.Heatmap = function(opt_options) {
       ol.Object.getChangeEventType(ol.layer.HeatmapLayerProperty.GRADIENT),
       this.handleGradientChanged_, false, this);
 
-  goog.events.listen(this,
-      ol.Object.getChangeEventType(ol.layer.HeatmapLayerProperty.RADIUS),
-      this.handleStyleChanged_, false, this);
+  goog.events.listen(this, [
+    ol.Object.getChangeEventType(ol.layer.HeatmapLayerProperty.BLUR),
+    ol.Object.getChangeEventType(ol.layer.HeatmapLayerProperty.RADIUS)
+  ], this.handleStyleChanged_, false, this);
+
+  this.setBlur(goog.isDef(options.blur) ? options.blur : 15);
 
   this.setGradient(goog.isDef(options.gradient) ?
       options.gradient : ol.layer.Heatmap.DEFAULT_GRADIENT);
@@ -168,11 +166,12 @@ ol.layer.Heatmap.createGradient_ = function(colors) {
  */
 ol.layer.Heatmap.prototype.createCircle_ = function() {
   var radius = this.getRadius();
-  var halfSize = radius + this.blur_ + 1;
+  var blur = this.getBlur();
+  var halfSize = radius + blur + 1;
   var size = 2 * halfSize;
   var context = ol.dom.createCanvasContext2D(size, size);
   context.shadowOffsetX = context.shadowOffsetY = this.shadow_;
-  context.shadowBlur = this.blur_;
+  context.shadowBlur = blur;
   context.shadowColor = '#000';
   context.beginPath();
   var center = halfSize - this.shadow_;
@@ -182,6 +181,20 @@ ol.layer.Heatmap.prototype.createCircle_ = function() {
 };
 
 
+/**
+ * @return {number} Blur size in pixels.
+ * @api
+ * @observable
+ */
+ol.layer.Heatmap.prototype.getBlur = function() {
+  return /** @type {number} */ (this.get(ol.layer.HeatmapLayerProperty.BLUR));
+};
+goog.exportProperty(
+    ol.layer.Heatmap.prototype,
+    'getBlur',
+    ol.layer.Heatmap.prototype.getBlur);
+
+
 /**
  * @return {Array.<string>} Colors.
  * @api
@@ -252,6 +265,20 @@ ol.layer.Heatmap.prototype.handleRender_ = function(event) {
 };
 
 
+/**
+ * @param {number} blur Blur size in pixels.
+ * @api
+ * @observable
+ */
+ol.layer.Heatmap.prototype.setBlur = function(blur) {
+  this.set(ol.layer.HeatmapLayerProperty.BLUR, blur);
+};
+goog.exportProperty(
+    ol.layer.Heatmap.prototype,
+    'setBlur',
+    ol.layer.Heatmap.prototype.setBlur);
+
+
 /**
  * @param {Array.<string>} colors Gradient.
  * @api