Several changes to get the performance on dragging back in check.

lib/timeline/Core.js

@@ -29,6 +29,7 @@ Emitter(Core.prototype);
  */
 Core.prototype._create = function (container) {
   this.dom = {};
+  this.options = {};
 
   this.dom.container = container;
 
@@ -91,7 +92,7 @@ Core.prototype._create = function (container) {
   this.dom.rightContainer.appendChild(this.dom.shadowBottomRight);
 
   this.on('rangechange', function () {
-    if (this.initialDrawDone) {
+    if (this.initialDrawDone === true) {
       this._redraw(); // this allows overriding the _redraw method
     }
   }.bind(this));
@@ -226,6 +227,7 @@ Core.prototype.setOptions = function (options) {
     ];
     util.selectiveExtend(fields, this.options, options);
 
+    this.options.orientation = {item:undefined,axis:undefined};
     if ('orientation' in options) {
       if (typeof options.orientation === 'string') {
         this.options.orientation = {
@@ -986,7 +988,6 @@ Core.prototype._onDrag = function (event) {
 
 
   if (newScrollTop != oldScrollTop) {
-    this._redraw(); // TODO: this causes two redraws when dragging, the other is triggered by rangechange already
     this.emit("verticalDrag");
   }
 };

lib/timeline/Range.js

@@ -429,10 +429,14 @@ Range.prototype._onDrag = function (event) {
   this.previousDelta = delta;
   this._applyRange(newStart, newEnd);
 
+
+  var startDate = new Date(this.start);
+  var endDate = new Date(this.end);
+
   // fire a rangechange event
   this.body.emitter.emit('rangechange', {
-    start: new Date(this.start),
-    end:   new Date(this.end),
+    start: startDate,
+    end:   endDate,
     byUser: true
   });
 };

lib/timeline/component/LineGraph.js

@@ -509,11 +509,6 @@ LineGraph.prototype.redraw = function () {
     - this.body.domProps.border.top
     - this.body.domProps.border.bottom;
 
-  // update the graph if there is no lastWidth or width, used for the initial draw
-  if (this.lastWidth === undefined && this.props.width) {
-    this.forceGraphUpdate = true;
-  }
-
   // check if this component is resized
   resized = this._isResized() || resized;