[Mobile, Gestures] Pinch

Pinch gesture being implemented.
Currently tracks two touchChanges
that track location and find distance
between them. Logs the distances currently.

platform/commonUI/browse/bundle.json

@@ -55,7 +55,8 @@
             {
                 "key": "browse-object",
                 "templateUrl": "templates/browse-object.html",
-                "uses": [ "view" ]
+                "uses": [ "view" ],
+                "gestures": [ "pinch" ]
             },
             {
                 "key": "create-button",

platform/representation/bundle.json

@@ -27,6 +27,11 @@
                 "key": "menu",
                 "implementation": "gestures/ContextMenuGesture.js",
                 "depends": ["$timeout", "agentService"]
+            },
+            {
+                "key": "pinch",
+                "implementation": "gestures/PinchGesture.js",
+                "depends": ["$log", "agentService"]
             }
         ],
         "components": [

platform/representation/src/gestures/PinchGesture.js

@@ -0,0 +1,125 @@
+/*****************************************************************************
+ * Open MCT Web, Copyright (c) 2014-2015, United States Government
+ * as represented by the Administrator of the National Aeronautics and Space
+ * Administration. All rights reserved.
+ *
+ * Open MCT Web is licensed under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * http://www.apache.org/licenses/LICENSE-2.0.
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ * Open MCT Web includes source code licensed under additional open source
+ * licenses. See the Open Source Licenses file (LICENSES.md) included with
+ * this source code distribution or the Licensing information page available
+ * at runtime from the About dialog for additional information.
+ *****************************************************************************/
+/*global define,Promise*/
+
+/**
+ * Module defining DragGesture. Created by vwoeltje on 11/17/14.
+ */
+define(
+    ['./GestureConstants'],
+    function (GestureConstants) {
+        "use strict";
+
+        /**
+         * Add event handlers to a representation such that it may be
+         * dragged as the source for drag-drop composition.
+         *
+         * @constructor
+         * @param $log Angular's logging service
+         * @param element the jqLite-wrapped element which should become
+         *        draggable
+         * @param {DomainObject} domainObject the domain object which
+         *        is represented; this will be passed on drop.
+         */
+        function PinchGesture($log, agentService, element, domainObject) {
+            var touchOneX,
+                touchOneY,
+                touchTwoX,
+                touchTwoY,
+                distance;
+            
+            function trackTouchOne(event) {
+                if (event) {
+                    touchOneX = event.clientX;
+                    touchOneY = event.clientY;
+                }
+            }
+            
+            function trackTouchTwo(event) {
+                if (event) {
+                    touchTwoX = event.clientX;
+                    touchTwoY = event.clientY;
+                }
+            }
+            
+            function findDistance() {
+                var squareX = Math.pow(touchOneX - touchTwoX, 2),
+                    squareY = Math.pow(touchOneY - touchTwoY, 2);
+//                $log.warn(" MATHSQRT(" + squareX + " + " + squareY + ")");
+                return Math.sqrt(squareX + squareY);
+            }
+            
+            function pinchStartAction(event) {
+                if (event.changedTouches.length === 2) {
+                    trackTouchOne(event.changedTouches[0]);
+                    trackTouchTwo(event.changedTouches[1]);
+                    
+                    var distance = findDistance();
+                    
+                    $log.warn("START DIST: " + distance);
+                    
+                    event.preventDefault();
+                }
+            }
+            
+            function pinchMoveAction(event) {
+                if (event.changedTouches.length === 2) {
+                    trackTouchOne(event.changedTouches[0]);
+                    trackTouchTwo(event.changedTouches[1]);
+                    
+                    var distance = findDistance();
+                    $log.warn("MOVE DIST: " + distance);
+                    
+                    event.preventDefault();
+                }
+            }
+            function pinchEndAction(event) {
+                if (event.changedTouches.length === 2) {
+                    trackTouchOne(event.changedTouches[0]);
+                    trackTouchTwo(event.changedTouches[1]);
+                    
+                    var distance = findDistance();
+                    $log.warn("END DIST: " + distance);
+                    
+                    event.preventDefault();
+                }
+            }
+            // Need to start the touch, transition to a touch move,
+            // Then capture the coordinates during every single touch 
+            // move, updating as movement is done. Keep in mind it is
+            // two different touches, and therefore 2 sets of coordinates
+            // Having these two sets allows manipulation and we can also take
+            // the distance between them and find the difference to then scale and
+            // accomplish pinch to zoom properly.
+            if (agentService.isMobile(navigator.userAgent)) {
+                element.on('touchstart', pinchStartAction);
+                element.on('touchmove', pinchMoveAction);
+                element.on('touchend', pinchEndAction);
+            }
+            return {
+
+            };
+        }
+
+        return PinchGesture;
+    }
+);