Improve analog mouse wheel detection and normalize event.wheelDelta for Safari

lib/OpenLayers/Handler/MouseWheel.js

@@ -55,6 +55,13 @@ OpenLayers.Handler.MouseWheel = OpenLayers.Class(OpenLayers.Handler, {
      */
     cumulative: true,
     
+    /**
+     * APIProperty: isAnalogScrollWheel
+     * {Boolean} Will switch to true when an event with analog scroll value
+     * is detected.
+     */
+    isAnalogScrollWheel: false,
+    
     /**
      * Property: analogWheelPrecision
      * {Integer} Adjust to get analog scroll wheel to feel right
@@ -175,16 +182,24 @@ OpenLayers.Handler.MouseWheel = OpenLayers.Class(OpenLayers.Handler, {
                 if (!e) {
                     e = window.event;
                 }
+                
                 if (e.wheelDelta) {
                     delta = e.wheelDelta;
-                    if (delta % 120 === 0) {
+                    
-                        delta = delta / 120;
+                    if (OpenLayers.BROWSER_NAME === "safari" && !this.isAnalogScrollWheel) {
-                    } else {
+                        delta = delta * 10;
-                        delta = delta / this.analogWheelPrecision;
+                    } else if (window.opera && window.opera.version() < 9.2) {
-                    }
-                    if (window.opera && window.opera.version() < 9.2) {
                         delta = -delta;
                     }
+                    
+                    this.isAnalogScrollWheel = (this.isAnalogScrollWheel ||
+                        delta % 40 !== 0 || Math.abs(delta) < 120);
+                    
+                    if (this.isAnalogScrollWheel) {
+                        delta = delta / this.analogWheelPrecision;
+                    } else {
+                        delta = Math.round(delta / 120);
+                    }
                 } else if (e.detail) {
                     delta = -e.detail / 3;
                 }

tests/Handler/MouseWheel.html

@@ -108,7 +108,8 @@
         var activated = handler.activate();
         
         var delta = 120;
-        if (window.opera && window.opera.version() < 9.2)  delta = -delta;
+        if (window.opera && window.opera.version() < 9.2) { delta = -delta; }
+        if (OpenLayers.BROWSER_NAME === "safari") delta = delta / 10;
         handler.onWheelEvent({'target':map.layers[0].div, wheelDelta: delta});
         handler.onWheelEvent({'target':map.layers[0].div, wheelDelta: delta});
         t.delay_call(1, function() {