1 files changed, 102 insertions, 0 deletions
diff --git a/misc/openlayers/lib/OpenLayers/Animation.js b/misc/openlayers/lib/OpenLayers/Animation.js
new file mode 100644
index 0000000..7b47a08
--- /dev/null
+++ b/misc/openlayers/lib/OpenLayers/Animation.js
@@ -0,0 +1,102 @@
+/* Copyright (c) 2006-2013 by OpenLayers Contributors (see authors.txt for
+ * full list of contributors). Published under the 2-clause BSD license.
+ * See license.txt in the OpenLayers distribution or repository for the
+ * full text of the license. */
+
+/**
+ * @requires OpenLayers/SingleFile.js
+ * @requires OpenLayers/Util/vendorPrefix.js
+ */
+
+/**
+ * Namespace: OpenLayers.Animation
+ * A collection of utility functions for executing methods that repaint a 
+ *     portion of the browser window.  These methods take advantage of the
+ *     browser's scheduled repaints where requestAnimationFrame is available.
+ */
+OpenLayers.Animation = (function(window) {
+    
+    /**
+     * Property: isNative
+     * {Boolean} true if a native requestAnimationFrame function is available
+     */
+    var requestAnimationFrame = OpenLayers.Util.vendorPrefix.js(window, "requestAnimationFrame");
+    var isNative = !!(requestAnimationFrame);
+    
+    /**
+     * Function: requestFrame
+     * Schedule a function to be called at the next available animation frame.
+     *     Uses the native method where available.  Where requestAnimationFrame is
+     *     not available, setTimeout will be called with a 16ms delay.
+     *
+     * Parameters:
+     * callback - {Function} The function to be called at the next animation frame.
+     * element - {DOMElement} Optional element that visually bounds the animation.
+     */
+    var requestFrame = (function() {
+        var request = window[requestAnimationFrame] ||
+            function(callback, element) {
+                window.setTimeout(callback, 16);
+            };
+        // bind to window to avoid illegal invocation of native function
+        return function(callback, element) {
+            request.apply(window, [callback, element]);
+        };
+    })();
+    
+    // private variables for animation loops
+    var counter = 0;
+    var loops = {};
+    
+    /**
+     * Function: start
+     * Executes a method with <requestFrame> in series for some 
+     *     duration.
+     *
+     * Parameters:
+     * callback - {Function} The function to be called at the next animation frame.
+     * duration - {Number} Optional duration for the loop.  If not provided, the
+     *     animation loop will execute indefinitely.
+     * element - {DOMElement} Optional element that visually bounds the animation.
+     *
+     * Returns:
+     * {Number} Identifier for the animation loop.  Used to stop animations with
+     *     <stop>.
+     */
+    function start(callback, duration, element) {
+        duration = duration > 0 ? duration : Number.POSITIVE_INFINITY;
+        var id = ++counter;
+        var start = +new Date;
+        loops[id] = function() {
+            if (loops[id] && +new Date - start <= duration) {
+                callback();
+                if (loops[id]) {
+                    requestFrame(loops[id], element);
+                }
+            } else {
+                delete loops[id];
+            }
+        };
+        requestFrame(loops[id], element);
+        return id;
+    }
+    
+    /**
+     * Function: stop
+     * Terminates an animation loop started with <start>.
+     *
+     * Parameters:
+     * id - {Number} Identifier returned from <start>.
+     */
+    function stop(id) {
+        delete loops[id];
+    }
+    
+    return {
+        isNative: isNative,
+        requestFrame: requestFrame,
+        start: start,
+        stop: stop
+    };
+    
+})(window);