From 5b85f8ecc993367e1a1fb476b6278fed3fda255a Mon Sep 17 00:00:00 2001
From: Tim Schaub <tim.schaub@gmail.com>
Date: Sun, 13 Nov 2016 10:25:20 -0700
Subject: [PATCH 1/2] Render on view changes

---
 src/ol/map.js            | 14 +++++++++++++-
 test/spec/ol/map.test.js | 17 +++++++++++++++++
 2 files changed, 30 insertions(+), 1 deletion(-)

diff --git a/src/ol/map.js b/src/ol/map.js
index 91ef5674ee..fe14b3aed9 100644
--- a/src/ol/map.js
+++ b/src/ol/map.js
@@ -216,6 +216,12 @@ ol.Map = function(options) {
    */
   this.viewPropertyListenerKey_ = null;
 
+  /**
+   * @private
+   * @type {?ol.EventsKey}
+   */
+  this.viewChangeListenerKey_ = null;
+
   /**
    * @private
    * @type {Array.<ol.EventsKey>}
@@ -1102,11 +1108,18 @@ ol.Map.prototype.handleViewChanged_ = function() {
     ol.events.unlistenByKey(this.viewPropertyListenerKey_);
     this.viewPropertyListenerKey_ = null;
   }
+  if (this.viewChangeListenerKey_) {
+    ol.events.unlistenByKey(this.viewChangeListenerKey_);
+    this.viewChangeListenerKey_ = null;
+  }
   var view = this.getView();
   if (view) {
     this.viewPropertyListenerKey_ = ol.events.listen(
         view, ol.ObjectEventType.PROPERTYCHANGE,
         this.handleViewPropertyChanged_, this);
+    this.viewChangeListenerKey_ = ol.events.listen(
+        view, ol.events.EventType.CHANGE,
+        this.handleViewPropertyChanged_, this);
   }
   this.render();
 };
@@ -1221,7 +1234,6 @@ ol.Map.prototype.removeOverlay = function(overlay) {
  * @private
  */
 ol.Map.prototype.renderFrame_ = function(time) {
-
   var i, ii, viewState;
 
   var size = this.getSize();
diff --git a/test/spec/ol/map.test.js b/test/spec/ol/map.test.js
index f92a44b6e2..f2cc852f38 100644
--- a/test/spec/ol/map.test.js
+++ b/test/spec/ol/map.test.js
@@ -160,6 +160,23 @@ describe('ol.Map', function() {
       document.body.removeChild(target);
     });
 
+    it('is called when the view.changed() is called', function() {
+      var view = map.getView();
+
+      var spy = sinon.spy(map, 'render');
+      view.changed();
+      expect(spy.callCount).to.be(1);
+    });
+
+    it('is not called on view changes after the view has been removed', function() {
+      var view = map.getView();
+      map.setView(null);
+
+      var spy = sinon.spy(map, 'render');
+      view.changed();
+      expect(spy.callCount).to.be(0);
+    });
+
     it('calls renderFrame_ and results in an postrender event', function(done) {
 
       var spy = sinon.spy(map, 'renderFrame_');

From 0ac620c817f5628bc30da58c8f95f93ba01cef78 Mon Sep 17 00:00:00 2001
From: Tim Schaub <tim.schaub@gmail.com>
Date: Sun, 13 Nov 2016 10:25:45 -0700
Subject: [PATCH 2/2] Set interacting hint during trackpad scroll

---
 src/ol/interaction/mousewheelzoom.js | 32 +++++++++++++++++++++++++++-
 1 file changed, 31 insertions(+), 1 deletion(-)

diff --git a/src/ol/interaction/mousewheelzoom.js b/src/ol/interaction/mousewheelzoom.js
index 04acd0388d..6de7da4c1e 100644
--- a/src/ol/interaction/mousewheelzoom.js
+++ b/src/ol/interaction/mousewheelzoom.js
@@ -1,6 +1,7 @@
 goog.provide('ol.interaction.MouseWheelZoom');
 
 goog.require('ol');
+goog.require('ol.View');
 goog.require('ol.easing');
 goog.require('ol.events.EventType');
 goog.require('ol.has');
@@ -73,6 +74,18 @@ ol.interaction.MouseWheelZoom = function(opt_options) {
    */
   this.mode_ = undefined;
 
+  /**
+   * Trackpad events separated by this delay will be considered separate
+   * interactions.
+   * @type {number}
+   */
+  this.trackpadEventGap_ = 400;
+
+  /**
+   * @type {number|undefined}
+   */
+  this.trackpadTimeoutId_ = undefined;
+
   /**
    * The number of delta values per zoom level
    * @private
@@ -143,7 +156,7 @@ ol.interaction.MouseWheelZoom.handleEvent = function(mapBrowserEvent) {
     this.startTime_ = now;
   }
 
-  if (!this.mode_ || now - this.startTime_ > 400) {
+  if (!this.mode_ || now - this.startTime_ > this.trackpadEventGap_) {
     this.mode_ = Math.abs(delta) < 4 ?
         ol.interaction.MouseWheelZoom.Mode.TRACKPAD :
         ol.interaction.MouseWheelZoom.Mode.WHEEL;
@@ -151,6 +164,12 @@ ol.interaction.MouseWheelZoom.handleEvent = function(mapBrowserEvent) {
 
   if (this.mode_ === ol.interaction.MouseWheelZoom.Mode.TRACKPAD) {
     var view = map.getView();
+    if (this.trackpadTimeoutId_) {
+      clearTimeout(this.trackpadTimeoutId_);
+    } else {
+      view.setHint(ol.View.Hint.INTERACTING, 1);
+    }
+    this.trackpadTimeoutId_ = setTimeout(this.decrementInteractingHint_.bind(this), this.trackpadEventGap_);
     var resolution = view.getResolution() * Math.pow(2, delta / this.trackpadDeltaPerZoom_);
     var minResolution = view.getMinResolution();
     var maxResolution = view.getMaxResolution();
@@ -197,6 +216,17 @@ ol.interaction.MouseWheelZoom.handleEvent = function(mapBrowserEvent) {
 };
 
 
+/**
+ * @private
+ */
+ol.interaction.MouseWheelZoom.prototype.decrementInteractingHint_ = function() {
+  this.trackpadTimeoutId_ = undefined;
+  var view = this.getMap().getView();
+  view.setHint(ol.View.Hint.INTERACTING, -1);
+  view.changed(); // notify listeners of the hint change
+};
+
+
 /**
  * @private
  * @param {ol.Map} map Map.