Add getObjectsAtLocation method in Arcade physics.

Author: pjbaron

src/physics/arcade/World.js

@@ -1407,32 +1407,51 @@ Phaser.Physics.Arcade.prototype = {
             return;
         }
 
+        return this.getObjectsAtLocation(pointer.x, pointer.y, group, callback, callbackContext, pointer);
+
+    },
+
+    /**
+    * Given a Group and a location this will check to see which Group children overlap with the coordinates.
+    * Each child will be sent to the given callback for further processing.
+    * Note that the children are not checked for depth order, but simply if they overlap the coordinate or not.
+    *
+    * @method Phaser.Physics.Arcade#getObjectsAtLocation
+    * @param {Phaser.Pointer} pointer - The Pointer to check.
+    * @param {Phaser.Group} group - The Group to check.
+    * @param {function} [callback] - A callback function that is called if the object overlaps the coordinates. The callback will be sent two parameters: the callbackArg and the Object that overlapped the location.
+    * @param {object} [callbackContext] - The context in which to run the callback.
+    * @param {object} [callbackArg] - An argument to pass to the callback.
+    * @return {array} An array of the Sprites from the Group that overlapped the coordinates.
+    */
+    getObjectsAtLocation: function (x, y, group, callback, callbackContext, callbackArg) {
+
         this.quadTree.clear();
 
         this.quadTree.reset(this.game.world.bounds.x, this.game.world.bounds.y, this.game.world.bounds.width, this.game.world.bounds.height, this.maxObjects, this.maxLevels);
 
         this.quadTree.populate(group);
 
-        var rect = new Phaser.Rectangle(pointer.x, pointer.y, 1, 1);
+        var rect = new Phaser.Rectangle(x, y, 1, 1);
         var output = [];
 
         this._potentials = this.quadTree.retrieve(rect);
 
         for (var i = 0, len = this._potentials.length; i < len; i++)
         {
-            if (this._potentials[i].hitTest(pointer.x, pointer.y))
+            if (this._potentials[i].hitTest(x, y))
             {
                 if (callback)
                 {
-                    callback.call(callbackContext, pointer, this._potentials[i].sprite);
+                    callback.call(callbackContext, callbackArg, this._potentials[i].sprite);
                 }
 
                 output.push(this._potentials[i].sprite);
             }
         }
 
         return output;
-
+        
     },
 
     /**