Add a renderBuffer option to ol.layer.Vector

src/ol/layer/vectorlayer.js

@@ -37,6 +37,13 @@ ol.layer.Vector = function(opt_options) {
   delete baseOptions.style;
   goog.base(this, /** @type {olx.layer.LayerOptions} */ (baseOptions));
 
+  /**
+   * @type {number}
+   * @private
+   */
+  this.renderBuffer_ = goog.isDef(options.renderBuffer) ?
+      options.renderBuffer : 100;
+
   /**
    * User provided style.
    * @type {ol.style.Style|Array.<ol.style.Style>|ol.style.StyleFunction}
@@ -57,6 +64,14 @@ ol.layer.Vector = function(opt_options) {
 goog.inherits(ol.layer.Vector, ol.layer.Layer);
 
 
+/**
+ * @return {number|undefined} Render buffer.
+ */
+ol.layer.Vector.prototype.getRenderBuffer = function() {
+  return this.renderBuffer_;
+};
+
+
 /**
  * @return {function(ol.Feature, ol.Feature): number|null|undefined} Render
  *     order.