/src/org/goasap/GoEngine.as
ActionScript | 1 lines | 1 code | 0 blank | 0 comment | 0 complexity | 85f9e427718043d6da29421bfc8270e7 MD5 | raw file
Possible License(s): LGPL-3.0
- /**
* Copyright (c) 2007 Moses Gunesch
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package org.goasap {
import flash.display.Sprite;
import flash.events.Event;
import flash.events.TimerEvent;
import flash.utils.Dictionary;
import flash.utils.Timer;
import flash.utils.getQualifiedClassName;
import flash.utils.getTimer;
import org.goasap.errors.DuplicateManagerError;
import org.goasap.interfaces.IManageable;
import org.goasap.interfaces.IManager;
import org.goasap.interfaces.IUpdatable;
import org.goasap.interfaces.ILiveManager;
/**
* Provides <code>update</code> calls to <code>IUpdatable</code> instances on their specified <code>pulseInterval</code>.
*
* <blockquote><blockquote>
* <p><b>Using these Docs</b></p>
*
* <p><i>Protected methods and properties have been excluded in almost all
* cases, but are documented in the classes. Exceptions include key protected
* methods or properties that are integral for writing subclasses or understanding
* the basic mechanics of the system. Many Go classes can be used as is without
* subclassing, so the documentation offers an uncluttered view of their public
* usage.</i></p>
*
* <p><b>Introduction to Go</b> <font color="#CC0000">[This section updated recently!]</font></p>
*
* <p>The Go ActionScript Animation Platform ("GOASAP") is a lightweight, portable
* set of generic base classes for buliding AS3 animation tools. It provides structure
* and core functionality, but does not define the specifics of animation-handling
* classes like tweens.</p>
*
* <p>GoASAP could be broken up into the following general layers:
* <ul>
* <li><i>Compatibility:</i> In general, this layer can be used in about any animation
* system. GoEngine, GoEvent, PlayStates and IPlayable.</li>
* <li><i>Items:</i> Base classes for utilities and animation items: PlayableBase, GoItem,
* LinearGo and PhysicsGo.</li>
* <li><i>Utilities:</i> You can write utility classes to manage items. Go ships with a
* few common ones: a parallel item class called PlayableGroup, and several Sequence classes.</li>
* <li><i>Automation/Management:</i> GoEngine provides a simple, centralized and fully extensible
* way for you to automate any time-based process and manage multiple items at once.</li>
* </ul></p>
*
* <p>GoASAP provides an intentionally loose standard, in that it does not intend to limit
* the possibilities of what can be built with it. Its primary benefits are compatibility and
* synchronicity between animation systems, absolute extensibility into any time-based process,
* and a much faster and easier way to build your own animation tools from scratch.</p>
*
* <p><i>Important: Store your custom Go classes in a package bearing your own classpath, not
* in the core package! This will help avoid confusion with other authors' work.</i></p>
*
* <p><font size="-2">You may modify any class in the goasap package to suit your project's needs. Your input
* is valuable! Please join the mailing list and share your Go-based animation tools at the
* GoPlayground repository. The GoASAP initiative is led by Moses Gunesch at
* <a href="http://www.mosessupposes.com/" target="_top">MosesSupposes.com</a>. Please visit the
* <a href="http://www.goasap.org/" target="_top">Go website</a> for more information.</font></p>
* </blockquote></blockquote>
*
* <p><b>GoEngine</b> <font color="#CC0000">[This section updated recently!]</font></p>
*
* <p>GoEngine sits at the center of the Go system, and along with the IUpdatable
* interface is the only required element for using GoASAP. GoEngine manages tightly
* synchronized item lists, since updating items in groups enhances efficiency. An
* advantage of GoASAP is that wildly different animation systems can be used together
* in the same project. Their synchronous updates will remain as efficient as possible,
* instead of fighting one another for processor cycles.</p>
*
* <p>GoEngine's default pulse rate is ENTER_FRAME which yields the smoothest processing in the
* Flash Player. However, it does not run on any one specific pulse. Instead, any object that is
* IUpdatable may specify its own pulse rate, and items with matching pulses are automatically
* grouped into update lists for efficiency. On a fine-tuning level, GoEngine uses a few other
* tricks to try and provide the tightest possible visual synchronization for larger batches of
* animation items. It passes the clock time at the start of each update cycle to each item in
* that list, which can be used in place of realtime to counteract any offset due to processing
* lag during the cycle. Additionally, items that get added <i>during</i> an update cycle are
* queued until the next update.</p>
*
* <p>GoASAP's management layer is made up of three interfaces that are referenced by GoEngine:
* IManager, ILiveManager and IManageable. Managers are always optional in GoASAP, and are only
* activated by calling <code>GoEngine.addManager()</code>. Managers can automate processes
* as items are added and removed, such as the included OverlapMonitor class which prevents
* property conflicts between items, or they can automate "live" processes that occur on each
* pulse. No live managers are included but an example might be a class that re-renders a 3D
* viewport after all 3D tweens have been processed. This can of course be done without a custom
* manager, but by using GoASAP you gain a unique ability to very cleanly and simply tie any
* custom routines in your project right into your animation processing, in perfect sync and
* with maximum efficiency.</p>
*
* <p></i>{In the game of Go, the wooden playing board, or Goban, features a grid
* on which black & white go-ishi stones are laid at its intersections.}</i></p>
*
* @see org.goasap.items.LinearGo LinearGo
* @see org.goasap.interfaces.IManager IManager
* @author Moses Gunesch
*/
public class GoEngine
{
// -== Constants ==-
public static const INFO:String = "GoASAP 0.5.0 (c) Moses Gunesch, MIT Licensed.";
// -== Settable Class Defaults ==-
/**
* A pulseInterval that runs on the player's natural framerate,
* which is often most efficient.
*/
public static const ENTER_FRAME : int = -1;
// -== Protected Properties ==-
// Note: Various formats for item data have been experimented with including breaking the item lists out into
// a GoEngineList class, which was nicer-looking but did not perform well. Since GoEngine doesn't normally
// require active work, this less-pretty but efficient flat-data format was opted for. A minor weakness of this
// format is its use of a Dictionary, which means update calls are not ordered like they would be with an Array.
// The Dictionary stores items' pulseInterval values, which is safer than relying on items to not change them.
// Tests also show that Dictionary performs faster than Array for accessing and deleting items.
private static var managerTable : Object = new Object(); // registration list of IManager instances
private static var managers : Array = new Array(); // ordered registration list of IManager instances
private static var liveManagers : uint = 0;
private static var timers : Dictionary = new Dictionary(false); // key: pulseInterval, value: Timer for that pulse
private static var items : Dictionary = new Dictionary(false); // key: IUpdatable item, value: pulseInterval at add.
private static var itemCounts : Dictionary = new Dictionary(false); // key: pulseInterval, value: item count for that pulse
private static var pulseSprite : Sprite; // used for ENTER_FRAME pulse
private static var paused : Boolean = false;
// These additional lists enables caching of items that are added during the update cycle for the same pulse.
// This prevents groups & sequences from going out of sync by ensuring that each cycle completes before new items are added.
private static var lockedPulses : Dictionary = new Dictionary(false); // key: pulseInterval, value: true
private static var delayedPulses : Dictionary = new Dictionary(false); // key: pulseInterval, value: true
private static var addQueue : Dictionary = new Dictionary(false); // key: IUpdatable item, value: true
// -== Public Class Methods ==-
/**
* @param className A string naming the manager class, such as "OverlapMonitor".
* @return The manager instance, if registered.
* @see #addManager()
* @see #removeManager()
*/
public static function getManager(className:String) : IManager
{
return managerTable[ className ];
}
/**
* Enables the extending of this class' functionality with a tight
* coupling to an IManager.
*
* <p>Tight coupling is crucial in such a time-sensitive context;
* standard events are too asynchronous. All items that implement
* IManageable are reported to registered managers as they add and
* remove themselves from GoEngine.</p>
*
* <p>Managers normally act as singletons within the Go system (which
* you are welcome to modify). This method throws a DuplicateManagerError
* if an instance of the same manager class is already registered. Use a
* try/catch block when calling this method if your program might duplicate
* managers, or use getManager() to check for prior registration.</p>
*
* @param instance An instance of a manager you wish to add.
* @see #getManager()
* @see #removeManager()
*/
public static function addManager( instance:IManager ):void
{
var className:String = getQualifiedClassName(instance);
className = className.slice(className.lastIndexOf("::")+2);
if (managerTable[ className ]) {
throw new DuplicateManagerError( className );
return;
}
managerTable[ className ] = instance;
managers.push(instance);
if (instance is ILiveManager) liveManagers++;
}
/**
* Unregisters any manager set in <code>addManager</code>.
*
* @param className A string naming the manager class, such as "OverlapMonitor".
* @see #getManager()
* @see #addManager()
*/
public static function removeManager( className:String ):void
{
managers.splice(managers.indexOf(managerTable[ className ]), 1);
if (managerTable[ className ] is ILiveManager)
liveManagers--;
delete managerTable[ className ]; // leave last
}
/**
* Test whether an item is currently stored and being updated by the engine.
*
* @param item Any object implementing IUpdatable
* @return Whether the IUpdatable is in the engine
*/
public static function hasItem( item:IUpdatable ):Boolean
{
return (items[ item ]!=null);
}
/**
* Adds an IUpdatable instance to an update-queue corresponding to
* the item's pulseInterval property.
*
* @param item Any object implementing IUpdatable that wishes
* to receive update calls on a pulse.
*
* @return Returns false only if this item was already in the
* engine under the same pulse. (If an existing item is added
* but the pulseInterval has changed it will be removed,
* re-added, and true will be returned.)
*
* @see #removeItem()
*/
public static function addItem( item:IUpdatable ):Boolean
{
// Group items by pulse for efficient update cycles.
var interval:int = item.pulseInterval;
if (items[ item ]) {
if (items[ item ] == item.pulseInterval)
return false;
else
removeItem(item);
}
if (lockedPulses[ interval ]==true) { // this prevents items from being added during an update loop in progress.
delayedPulses[ interval ] = true; // flags update to clear the queue when the in-progress loop completes.
addQueue[ item ] = true; // for tightest syncing of item groups, read the documentation under GoItem.update().
}
items[ item ] = interval; // Tether item to original pulseint. Used in removeItem & setPaused(false).
if (!timers[ interval ]) {
addPulse( interval );
itemCounts[ interval ] = 1;
}
else {
itemCounts[ interval ] ++;
}
// Report IManageable instances to registered managers
if (item is IManageable) {
for each (var manager:IManager in managers)
manager.reserve( item as IManageable );
}
return true;
}
/**
* Removes an item from the queue and removes its pulse timer if
* the queue is depleted.
*
* @param item Any IUpdatable previously added that wishes
* to stop receiving update calls.
*
* @return Returns false if the item was not in the engine.
*
* @see #addItem()
*/
public static function removeItem( item:IUpdatable ):Boolean
{
if (items[ item ]==null)
return false;
var interval: int = items[ item ];
if ( -- itemCounts[ interval ] == 0 ) {
removePulse( interval );
delete itemCounts[ interval ];
}
delete items[ item ];
delete addQueue[ item ]; // * see note following update
// Report IManageable item removal to registered managers.
if (item is IManageable) {
for each (var manager:IManager in managers)
manager.release( item as IManageable );
}
return true;
}
/**
* Removes all items and resets the engine,
* or removes just items running on a specific pulse.
*
* @param pulseInterval Optionally filter by a specific pulse
* such as ENTER_FRAME or a number of milliseconds.
* @return The number of items successfully removed.
* @see #removeItem()
*/
public static function clear(pulseInterval:Number = NaN) : uint
{
var all:Boolean = (isNaN(pulseInterval));
var n:Number = 0;
for (var item:Object in items) {
if (all || items[ item ]==pulseInterval)
if (removeItem(item as IUpdatable)==true)
n++;
}
return n;
}
/**
* Retrieves number of active items in the engine
* or active items running on a specific pulse.
*
* @param pulseInterval Optionally filter by a specific pulseInterval
* such as ENTER_FRAME or a number of milliseconds.
*
* @return Number of active items in the Engine.
*/
public static function getCount(pulseInterval:Number = NaN) : uint
{
if (!isNaN(pulseInterval))
return (itemCounts[pulseInterval]);
var n:Number = 0;
for each (var count: int in itemCounts)
n += count;
return n;
}
/**
* @return The paused state of engine.
* @see #setPaused()
*/
public static function getPaused() : Boolean {
return paused;
}
/**
* Pauses or resumes all animation globally by suspending processing,
* and calls pause() or resume() on each item with those methods.
*
* <p>The return value only reflects how many items had pause() or resume()
* called on them, but the GoEngine.getPaused() state will change if any
* pulses are suspended or resumed.</p>
*
* @param pause Pass false to resume if currently paused.
* @param pulseInterval Optionally filter by a specific pulse
* such as ENTER_FRAME or a number of milliseconds.
* @return The number of items on which a pause() or resume()
* method was called (0 doesn't necessarily reflect
* whether the GoEngine.getPaused() state changed, it
* may simply indicate that no items had that method).
* @see #resume()
*/
public static function setPaused(pause:Boolean=true, pulseInterval:Number = NaN) : uint
{
if (paused==pause) return 0;
var n:Number = 0;
var pulseChanged:Boolean = false;
var all:Boolean = (isNaN(pulseInterval));
var method:String = (pause ? "pause" : "resume");
for (var item:Object in items) {
var pulse:int = (items[item] as int);
if (all || pulse==pulseInterval) {
pulseChanged = (pulseChanged || (pause ? removePulse(pulse) : addPulse(pulse)));
// call pause or resume on the item if it has such a method.
if (item.hasOwnProperty(method)) {
if (item[method] is Function) {
item[method].apply(item);
n++;
}
}
}
}
if (pulseChanged)
paused = pause;
return n;
}
// -== Private Class Methods ==-
/**
* Executes the update queue corresponding to the dispatcher's interval.
*
* @param event TimerEvent or Sprite ENTER_FRAME Event
*/
private static function update(event:Event) : void
{
var currentTime:Number = getTimer();
var pulse:int = (event is TimerEvent ? ( event.target as Timer ).delay : ENTER_FRAME);
lockedPulses[ pulse ] = true;
var doLiveUpdate:Boolean = (liveManagers > 0);
var updated:Array;
if (doLiveUpdate) updated = []; // syncs the live manager list to items actually updated
for (var item:* in items) {
if (items[ item ]==pulse && !addQueue[ item ]) {
(item as IUpdatable).update(currentTime);
if (doLiveUpdate) updated.push(item);
}
}
lockedPulses[ pulse ] = false;
if (delayedPulses[ pulse ]) {
for (item in addQueue)
delete addQueue[ item ];
delete delayedPulses[ pulse ];
}
// updateAfterEvent() should not be needed as long as items follow tight-syncing instructions in GoItem.update() documentation.
// if (pulse!=ENTER_FRAME) (event as TimerEvent).updateAfterEvent();
if (doLiveUpdate)
for each (var manager:Object in managers)
if (manager is ILiveManager)
(manager as ILiveManager).onUpdate(pulse, updated, currentTime); // * see note
}
// * note: In one rare case that has not been reported yet but is theoretically possible, the 'updated' list
// passed could contain already-released items. This could only happen if the item is removed & released
// just after the main update cycle but before the the doLiveUpdate() routine runs. If you encounter this issue
// please report it to the GoASAP mailing list, it's too involved to bother with before it's a problem.
/**
* Creates new timers when a previously unused interval is specified,
* and tracks the number of items associated with that interval.
*
* @param pulse The pulseInterval requested
* @return Whether a pulse was added
*/
private static function addPulse(pulse : int) : Boolean
{
if (pulse==ENTER_FRAME) {
if (!pulseSprite) {
timers[ENTER_FRAME] = pulseSprite = new Sprite();
pulseSprite.addEventListener(Event.ENTER_FRAME, update);
}
return true;
}
var t:Timer = timers[ pulse ] as Timer;
if (!t) {
t = timers[ pulse ] = new Timer(pulse);
(timers[ pulse ] as Timer).addEventListener(TimerEvent.TIMER, update);
t.start();
return true;
}
return false;
}
/**
* Tracks whether a removed item was the last one using a timer
* and if so, removes that timer.
*
* @param pulse The pulseInterval corresponding to an item being removed.
* @return Whether a pulse was removed
*/
private static function removePulse(pulse : int) : Boolean
{
if (pulse==ENTER_FRAME) {
if (pulseSprite) {
pulseSprite.removeEventListener(Event.ENTER_FRAME, update);
delete timers[ ENTER_FRAME ];
pulseSprite = null;
return true;
}
}
var t:Timer = timers[ pulse ] as Timer;
if (t) {
t.stop();
t.removeEventListener(TimerEvent.TIMER, update);
delete timers[ pulse ];
return true;
}
return false;
}
}
}