diff --git a/src/ol/interaction/interaction.js b/src/ol/interaction/interaction.js
index 2e45101983..a4e15be650 100644
--- a/src/ol/interaction/interaction.js
+++ b/src/ol/interaction/interaction.js
@@ -107,8 +107,8 @@ ol.interaction.Interaction.prototype.setMap = function(map) {
  */
 ol.interaction.Interaction.pan = function(map, view, delta, opt_duration) {
   var currentCenter = view.getCenter();
-  if (goog.isDef(currentCenter)) {
-    if (goog.isDef(opt_duration) && opt_duration > 0) {
+  if (currentCenter) {
+    if (opt_duration && opt_duration > 0) {
       map.beforeRender(ol.animation.pan({
         source: currentCenter,
         duration: opt_duration,
@@ -149,14 +149,14 @@ ol.interaction.Interaction.rotateWithoutConstraints =
   if (goog.isDefAndNotNull(rotation)) {
     var currentRotation = view.getRotation();
     var currentCenter = view.getCenter();
-    if (goog.isDef(currentRotation) && goog.isDef(currentCenter) &&
-        goog.isDef(opt_duration) && opt_duration > 0) {
+    if (currentRotation !== undefined && currentCenter &&
+        opt_duration && opt_duration > 0) {
       map.beforeRender(ol.animation.rotate({
         rotation: currentRotation,
         duration: opt_duration,
         easing: ol.easing.easeOut
       }));
-      if (goog.isDef(opt_anchor)) {
+      if (opt_anchor) {
         map.beforeRender(ol.animation.pan({
           source: currentCenter,
           duration: opt_duration,
@@ -220,14 +220,14 @@ ol.interaction.Interaction.zoomWithoutConstraints =
   if (goog.isDefAndNotNull(resolution)) {
     var currentResolution = view.getResolution();
     var currentCenter = view.getCenter();
-    if (goog.isDef(currentResolution) && goog.isDef(currentCenter) &&
-        goog.isDef(opt_duration) && opt_duration > 0) {
+    if (currentResolution !== undefined && currentCenter &&
+        opt_duration && opt_duration > 0) {
       map.beforeRender(ol.animation.zoom({
         resolution: currentResolution,
         duration: opt_duration,
         easing: ol.easing.easeOut
       }));
-      if (goog.isDef(opt_anchor)) {
+      if (opt_anchor) {
         map.beforeRender(ol.animation.pan({
           source: currentCenter,
           duration: opt_duration,