Give each source file a unique name

src/ol/interaction/dragpaninteraction.js

@@ -0,0 +1,57 @@
+goog.provide('ol.interaction.DragPan');
+
+goog.require('ol.Coordinate');
+goog.require('ol.MapBrowserEvent');
+goog.require('ol.interaction.ConditionType');
+goog.require('ol.interaction.Drag');
+
+
+
+/**
+ * @constructor
+ * @extends {ol.interaction.Drag}
+ * @param {ol.interaction.ConditionType} condition Condition.
+ */
+ol.interaction.DragPan = function(condition) {
+
+  goog.base(this);
+
+  /**
+   * @private
+   * @type {ol.interaction.ConditionType}
+   */
+  this.condition_ = condition;
+
+};
+goog.inherits(ol.interaction.DragPan, ol.interaction.Drag);
+
+
+/**
+ * @inheritDoc
+ */
+ol.interaction.DragPan.prototype.handleDrag = function(mapBrowserEvent) {
+  var map = mapBrowserEvent.map;
+  var resolution = map.getResolution();
+  var rotation = map.getRotation();
+  var delta =
+      new ol.Coordinate(-resolution * this.deltaX, resolution * this.deltaY);
+  if (map.canRotate() && goog.isDef(rotation)) {
+    delta.rotate(rotation);
+  }
+  var newCenter = new ol.Coordinate(
+      this.startCenter.x + delta.x, this.startCenter.y + delta.y);
+  map.setCenter(newCenter);
+};
+
+
+/**
+ * @inheritDoc
+ */
+ol.interaction.DragPan.prototype.handleDragStart = function(mapBrowserEvent) {
+  var browserEvent = mapBrowserEvent.browserEvent;
+  if (this.condition_(browserEvent)) {
+    return true;
+  } else {
+    return false;
+  }
+};