| // Copyright 2006 The Closure Library Authors. All Rights Reserved. |
| // |
| // 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. |
| |
| /** |
| * @fileoverview Basic animation controls. |
| * |
| * @author arv@google.com (Erik Arvidsson) |
| */ |
| goog.provide('goog.fx.anim'); |
| goog.provide('goog.fx.anim.Animated'); |
| |
| goog.require('goog.async.AnimationDelay'); |
| goog.require('goog.async.Delay'); |
| goog.require('goog.object'); |
| |
| |
| |
| /** |
| * An interface for programatically animated objects. I.e. rendered in |
| * javascript frame by frame. |
| * |
| * @interface |
| */ |
| goog.fx.anim.Animated = function() {}; |
| |
| |
| /** |
| * Function called when a frame is requested for the animation. |
| * |
| * @param {number} now Current time in milliseconds. |
| */ |
| goog.fx.anim.Animated.prototype.onAnimationFrame; |
| |
| |
| /** |
| * Default wait timeout for animations (in milliseconds). Only used for timed |
| * animation, which uses a timer (setTimeout) to schedule animation. |
| * |
| * @type {number} |
| * @const |
| */ |
| goog.fx.anim.TIMEOUT = goog.async.AnimationDelay.TIMEOUT; |
| |
| |
| /** |
| * A map of animations which should be cycled on the global timer. |
| * |
| * @type {Object<number, goog.fx.anim.Animated>} |
| * @private |
| */ |
| goog.fx.anim.activeAnimations_ = {}; |
| |
| |
| /** |
| * An optional animation window. |
| * @type {Window} |
| * @private |
| */ |
| goog.fx.anim.animationWindow_ = null; |
| |
| |
| /** |
| * An interval ID for the global timer or event handler uid. |
| * @type {goog.async.Delay|goog.async.AnimationDelay} |
| * @private |
| */ |
| goog.fx.anim.animationDelay_ = null; |
| |
| |
| /** |
| * Registers an animation to be cycled on the global timer. |
| * @param {goog.fx.anim.Animated} animation The animation to register. |
| */ |
| goog.fx.anim.registerAnimation = function(animation) { |
| var uid = goog.getUid(animation); |
| if (!(uid in goog.fx.anim.activeAnimations_)) { |
| goog.fx.anim.activeAnimations_[uid] = animation; |
| } |
| |
| // If the timer is not already started, start it now. |
| goog.fx.anim.requestAnimationFrame_(); |
| }; |
| |
| |
| /** |
| * Removes an animation from the list of animations which are cycled on the |
| * global timer. |
| * @param {goog.fx.anim.Animated} animation The animation to unregister. |
| */ |
| goog.fx.anim.unregisterAnimation = function(animation) { |
| var uid = goog.getUid(animation); |
| delete goog.fx.anim.activeAnimations_[uid]; |
| |
| // If a timer is running and we no longer have any active timers we stop the |
| // timers. |
| if (goog.object.isEmpty(goog.fx.anim.activeAnimations_)) { |
| goog.fx.anim.cancelAnimationFrame_(); |
| } |
| }; |
| |
| |
| /** |
| * Tears down this module. Useful for testing. |
| */ |
| // TODO(nicksantos): Wow, this api is pretty broken. This should be fixed. |
| goog.fx.anim.tearDown = function() { |
| goog.fx.anim.animationWindow_ = null; |
| goog.dispose(goog.fx.anim.animationDelay_); |
| goog.fx.anim.animationDelay_ = null; |
| goog.fx.anim.activeAnimations_ = {}; |
| }; |
| |
| |
| /** |
| * Registers an animation window. This allows usage of the timing control API |
| * for animations. Note that this window must be visible, as non-visible |
| * windows can potentially stop animating. This window does not necessarily |
| * need to be the window inside which animation occurs, but must remain visible. |
| * See: https://developer.mozilla.org/en/DOM/window.mozRequestAnimationFrame. |
| * |
| * @param {Window} animationWindow The window in which to animate elements. |
| */ |
| goog.fx.anim.setAnimationWindow = function(animationWindow) { |
| // If a timer is currently running, reset it and restart with new functions |
| // after a timeout. This is to avoid mismatching timer UIDs if we change the |
| // animation window during a running animation. |
| // |
| // In practice this cannot happen before some animation window and timer |
| // control functions has already been set. |
| var hasTimer = |
| goog.fx.anim.animationDelay_ && goog.fx.anim.animationDelay_.isActive(); |
| |
| goog.dispose(goog.fx.anim.animationDelay_); |
| goog.fx.anim.animationDelay_ = null; |
| goog.fx.anim.animationWindow_ = animationWindow; |
| |
| // If the timer was running, start it again. |
| if (hasTimer) { |
| goog.fx.anim.requestAnimationFrame_(); |
| } |
| }; |
| |
| |
| /** |
| * Requests an animation frame based on the requestAnimationFrame and |
| * cancelRequestAnimationFrame function pair. |
| * @private |
| */ |
| goog.fx.anim.requestAnimationFrame_ = function() { |
| if (!goog.fx.anim.animationDelay_) { |
| // We cannot guarantee that the global window will be one that fires |
| // requestAnimationFrame events (consider off-screen chrome extension |
| // windows). Default to use goog.async.Delay, unless |
| // the client has explicitly set an animation window. |
| if (goog.fx.anim.animationWindow_) { |
| // requestAnimationFrame will call cycleAnimations_ with the current |
| // time in ms, as returned from goog.now(). |
| goog.fx.anim.animationDelay_ = new goog.async.AnimationDelay( |
| function(now) { |
| goog.fx.anim.cycleAnimations_(now); |
| }, goog.fx.anim.animationWindow_); |
| } else { |
| goog.fx.anim.animationDelay_ = new goog.async.Delay(function() { |
| goog.fx.anim.cycleAnimations_(goog.now()); |
| }, goog.fx.anim.TIMEOUT); |
| } |
| } |
| |
| var delay = goog.fx.anim.animationDelay_; |
| if (!delay.isActive()) { |
| delay.start(); |
| } |
| }; |
| |
| |
| /** |
| * Cancels an animation frame created by requestAnimationFrame_(). |
| * @private |
| */ |
| goog.fx.anim.cancelAnimationFrame_ = function() { |
| if (goog.fx.anim.animationDelay_) { |
| goog.fx.anim.animationDelay_.stop(); |
| } |
| }; |
| |
| |
| /** |
| * Cycles through all registered animations. |
| * @param {number} now Current time in milliseconds. |
| * @private |
| */ |
| goog.fx.anim.cycleAnimations_ = function(now) { |
| goog.object.forEach(goog.fx.anim.activeAnimations_, function(anim) { |
| anim.onAnimationFrame(now); |
| }); |
| |
| if (!goog.object.isEmpty(goog.fx.anim.activeAnimations_)) { |
| goog.fx.anim.requestAnimationFrame_(); |
| } |
| }; |