From c7131678f85b5e77201d5c540c6c0de004c40502 Mon Sep 17 00:00:00 2001
From: jdescottes <julian.descottes@gmail.com>
Date: Sat, 24 Jan 2015 00:00:08 +0100
Subject: [PATCH] Fix mousewheel event for IE11

---
 src/js/controller/DrawingController.js | 31 ++++++++++++++++----------
 1 file changed, 19 insertions(+), 12 deletions(-)

diff --git a/src/js/controller/DrawingController.js b/src/js/controller/DrawingController.js
index cf185110..a167e3e9 100644
--- a/src/js/controller/DrawingController.js
+++ b/src/js/controller/DrawingController.js
@@ -79,7 +79,7 @@
     var body = $('body');
     this.container.mousedown($.proxy(this.onMousedown_, this));
 
-    if (pskl.utils.UserAgent.isChrome) {
+    if (pskl.utils.UserAgent.isChrome || pskl.utils.UserAgent.isIE11) {
       this.container.on('mousewheel', $.proxy(this.onMousewheel_, this));
     } else {
       this.container.on('wheel', $.proxy(this.onMousewheel_, this));
@@ -222,7 +222,14 @@
   ns.DrawingController.prototype.onMousewheel_ = function (jQueryEvent) {
     var event = jQueryEvent.originalEvent;
     // Ratio between wheelDeltaY (mousewheel event) and deltaY (wheel event) is -40
-    var delta = event.wheelDeltaY || (-40 * event.deltaY);
+    var delta;
+    if (pskl.utils.UserAgent.isChrome) {
+      delta = event.wheelDeltaY;
+    } else if (pskl.utils.UserAgent.isIE11) {
+      delta = event.wheelDelta;
+    } else if (pskl.utils.UserAgent.isFirefox) {
+      delta = -40 * event.deltaY;
+    }
     var modifier = Math.abs(delta/120);
     if (delta > 0) {
       this.increaseZoom_(modifier);
@@ -231,6 +238,16 @@
     }
   };
 
+  ns.DrawingController.prototype.increaseZoom_ = function (zoomMultiplier) {
+    var step = (zoomMultiplier || 1) * this.getZoomStep_();
+    this.setZoom_(this.renderer.getZoom() + step);
+  };
+
+  ns.DrawingController.prototype.decreaseZoom_ = function (zoomMultiplier) {
+    var step = (zoomMultiplier || 1) * this.getZoomStep_();
+    this.setZoom_(this.renderer.getZoom() - step);
+  };
+
   /**
    * @private
    */
@@ -397,16 +414,6 @@
     this.setZoom_(this.calculateZoom_());
   };
 
-  ns.DrawingController.prototype.increaseZoom_ = function (zoomMultiplier) {
-    var step = (zoomMultiplier || 1) * this.getZoomStep_();
-    this.setZoom_(this.renderer.getZoom() + step);
-  };
-
-  ns.DrawingController.prototype.decreaseZoom_ = function (zoomMultiplier) {
-    var step = (zoomMultiplier || 1) * this.getZoomStep_();
-    this.setZoom_(this.renderer.getZoom() - step);
-  };
-
   ns.DrawingController.prototype.getZoomStep_ = function () {
     return this.calculateZoom_() / 10;
   };