Director
– 导演类
管理场景Scene
实例化各种全局XXXX
绑定GLView
路径 1 2 cocos/2 d/CCDirector.h cocos/2 d/CCDirector.cpp
源码分析 先上一盘头文件。
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 class CC_DLL Director : public Ref{ public : static const char *EVENT_PROJECTION_CHANGED; static const char * EVENT_AFTER_UPDATE; static const char * EVENT_AFTER_VISIT; static const char * EVENT_AFTER_DRAW; enum class Projection { _2D, _3D, CUSTOM, DEFAULT = _3D, }; static Director* getInstance () ; CC_DEPRECATED_ATTRIBUTE static Director* sharedDirector () { return Director::getInstance(); } Director(void ); virtual ~Director(); virtual bool init () ; inline Scene* getRunningScene () { return _runningScene; } inline double getAnimationInterval () { return _animationInterval; } virtual void setAnimationInterval (double interval) = 0 ; inline bool isDisplayStats () { return _displayStats; } inline void setDisplayStats (bool displayStats) { _displayStats = displayStats; } inline float getSecondsPerFrame () { return _secondsPerFrame; } inline GLView* getOpenGLView () { return _openGLView; } void setOpenGLView (GLView *openGLView) ; TextureCache* getTextureCache () const ; inline bool isNextDeltaTimeZero () { return _nextDeltaTimeZero; } void setNextDeltaTimeZero (bool nextDeltaTimeZero) ; inline bool isPaused () { return _paused; } inline unsigned int getTotalFrames () { return _totalFrames; } inline Projection getProjection () { return _projection; } void setProjection (Projection projection) ; void setViewport () ; inline bool isSendCleanupToScene () { return _sendCleanupToScene; } Node* getNotificationNode () const { return _notificationNode; } void setNotificationNode (Node *node) ; const Size& getWinSize () const ; Size getWinSizeInPixels () const ; Size getVisibleSize () const ; Point getVisibleOrigin () const ; Point convertToGL (const Point& point) ; Point convertToUI (const Point& point) ; float getZEye () const ; void runWithScene (Scene *scene) ; void pushScene (Scene *scene) ; void popScene () ; void popToRootScene () ; void popToSceneStackLevel (int level) ; void replaceScene (Scene *scene) ; void end () ; void pause () ; void resume () ; virtual void stopAnimation () = 0 ; virtual void startAnimation () = 0 ; void drawScene () ; void purgeCachedData () ; void setDefaultValues () ; void setGLDefaultValues () ; void setAlphaBlending (bool on) ; void setDepthTest (bool on) ; virtual void mainLoop () = 0 ; void setContentScaleFactor (float scaleFactor) ; float getContentScaleFactor () const { return _contentScaleFactor; } Scheduler* getScheduler () const { return _scheduler; } void setScheduler (Scheduler* scheduler) ; ActionManager* getActionManager () const { return _actionManager; } void setActionManager (ActionManager* actionManager) ; EventDispatcher* getEventDispatcher () const { return _eventDispatcher; } void setEventDispatcher (EventDispatcher* dispatcher) ; Renderer* getRenderer () const { return _renderer; } #if (CC_TARGET_PLATFORM != CC_PLATFORM_WINRT) && (CC_TARGET_PLATFORM != CC_PLATFORM_WP8) Console* getConsole () const { return _console; } #endif float getDeltaTime () const ; float getFrameRate () const { return _frameRate; } protected : void purgeDirector () ; bool _purgeDirectorInNextLoop; void setNextScene () ; void showStats () ; void createStatsLabel () ; void calculateMPF () ; void getFPSImageData (unsigned char ** datapointer, ssize_t* length) ; void calculateDeltaTime () ; void initTextureCache () ; void destroyTextureCache () ; Scheduler *_scheduler; ActionManager *_actionManager; EventDispatcher* _eventDispatcher; EventCustom *_eventProjectionChanged, *_eventAfterDraw, *_eventAfterVisit, *_eventAfterUpdate; float _deltaTime; GLView *_openGLView; TextureCache *_textureCache; double _animationInterval; double _oldAnimationInterval; bool _landscape; bool _displayStats; float _accumDt; float _frameRate; LabelAtlas *_FPSLabel; LabelAtlas *_drawnBatchesLabel; LabelAtlas *_drawnVerticesLabel; bool _paused; unsigned int _totalFrames; unsigned int _frames; float _secondsPerFrame; Scene *_runningScene; Scene *_nextScene; bool _sendCleanupToScene; Vector<Scene*> _scenesStack; struct timeval *_lastUpdate; bool _nextDeltaTimeZero; Projection _projection; Size _winSizeInPoints; float _contentScaleFactor; Node *_notificationNode; Renderer *_renderer; #if (CC_TARGET_PLATFORM != CC_PLATFORM_WINRT) && (CC_TARGET_PLATFORM != CC_PLATFORM_WP8) Console *_console; #endif friend class GLViewProtocol; }; class DisplayLinkDirector : public Director{ public : DisplayLinkDirector() : _invalid(false ) {} virtual void mainLoop () override ; virtual void setAnimationInterval (double value) override ; virtual void startAnimation () override ; virtual void stopAnimation () override ; protected : bool _invalid; };
看了头文件之后,大概就有了一个了解 头文件的注释中表明基于Director
的子类或许会有4个,之后由于只需要DisplayLinkDirector
,便只实现了这个。
看过头文件之后便把把内容划分成以下几个模块:
Director实例化 先看看Director
的实例化方法:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 Director* Director::getInstance() { if (!s_SharedDirector) { s_SharedDirector = new DisplayLinkDirector(); s_SharedDirector->init(); } return s_SharedDirector; } bool Director::init(void ){ setDefaultValues(); _runningScene = nullptr ; _nextScene = nullptr ; _notificationNode = nullptr ; _scenesStack.reserve(15 ); _accumDt = 0.0f ; _frameRate = 0.0f ; _FPSLabel = _drawnBatchesLabel = _drawnVerticesLabel = nullptr ; _totalFrames = _frames = 0 ; _lastUpdate = new struct timeval; _paused = false ; _purgeDirectorInNextLoop = false ; _winSizeInPoints = Size::ZERO; _openGLView = nullptr ; _contentScaleFactor = 1.0f ; _scheduler = new Scheduler(); _actionManager = new ActionManager(); _scheduler->scheduleUpdate(_actionManager, Scheduler::PRIORITY_SYSTEM, false ); _eventDispatcher = new EventDispatcher(); _eventAfterDraw = new EventCustom(EVENT_AFTER_DRAW); _eventAfterDraw->setUserData(this ); _eventAfterVisit = new EventCustom(EVENT_AFTER_VISIT); _eventAfterVisit->setUserData(this ); _eventAfterUpdate = new EventCustom(EVENT_AFTER_UPDATE); _eventAfterUpdate->setUserData(this ); _eventProjectionChanged = new EventCustom(EVENT_PROJECTION_CHANGED); _eventProjectionChanged->setUserData(this ); initTextureCache(); _renderer = new Renderer; #if (CC_TARGET_PLATFORM != CC_PLATFORM_WINRT) && (CC_TARGET_PLATFORM != CC_PLATFORM_WP8) _console = new Console; #endif return true ; }
看到这个实例方法,以及初始化函数init
,就渐渐对Cocos2dx是怎么开始的,有了一定的了解。
Configuration配置一些相关设置,会在setOpenGLView的时候再次更新。
使用cocos2d::Vector来管理场景栈
初始化全局定时器,全局动坐管理类,全局事件管理类等等。
初始化纹理缓存
初始化渲染队列,Cocos2dx3.0开始,渲染都是放入放入一个渲染队列之中。
其他的就是Director的一些信息的设置啦
Director主循环 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 void DisplayLinkDirector::startAnimation(){ if (gettimeofday(_lastUpdate, nullptr ) != 0 ) { CCLOG("cocos2d: DisplayLinkDirector: Error on gettimeofday" ); } _invalid = false ; Application::getInstance()->setAnimationInterval(_animationInterval); setNextDeltaTimeZero(true ); } void DisplayLinkDirector::mainLoop(){ if (_purgeDirectorInNextLoop) { _purgeDirectorInNextLoop = false ; purgeDirector(); } else if (! _invalid) { drawScene(); PoolManager::getInstance()->getCurrentPool()->clear(); } } void DisplayLinkDirector::stopAnimation(){ _invalid = true ; } void DisplayLinkDirector::setAnimationInterval(double interval){ _animationInterval = interval; if (! _invalid) { stopAnimation(); startAnimation(); } }
主循环每一帧主要是调用drawScene
,主要是计算全局时间间隔,更新全局定时器,全局动作管理,获取输入事件,还有最重要的绘制。
当调用了stopAnimation
的时候,即_invalid
为false的时候,主循环就什么事情都不干了。
PS:对于PoolManager的相关东西见cocos2dx 3.0 —- AutoreleasePool, PoolManager
Director场景管理 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 void Director::runWithScene(Scene *scene){ CCASSERT(scene != nullptr , "This command can only be used to start the Director. There is already a scene present." ); CCASSERT(_runningScene == nullptr , "_runningScene should be null" ); pushScene(scene); startAnimation(); } void Director::replaceScene(Scene *scene){ CCASSERT(_runningScene, "Use runWithScene: instead to start the director" ); CCASSERT(scene != nullptr , "the scene should not be null" ); if (_nextScene) { if (_nextScene->isRunning()) { _nextScene->onExitTransitionDidStart(); _nextScene->onExit(); } _nextScene->cleanup(); _nextScene = nullptr ; } ssize_t index = _scenesStack.size(); _sendCleanupToScene = true ; _scenesStack.replace(index - 1 , scene); _nextScene = scene; } void Director::pushScene(Scene *scene)void Director::popScene(void )void Director::popToRootScene(void )void Director::popToSceneStackLevel(int level)void Director::end(){ _purgeDirectorInNextLoop = true ; } void Director::setNextScene(){ bool runningIsTransition = dynamic_cast <TransitionScene*>(_runningScene) != nullptr ; bool newIsTransition = dynamic_cast <TransitionScene*>(_nextScene) != nullptr ; if (! newIsTransition) { if (_runningScene) { _runningScene->onExitTransitionDidStart(); _runningScene->onExit(); } if (_sendCleanupToScene && _runningScene) { _runningScene->cleanup(); } } if (_runningScene) { _runningScene->release(); } _runningScene = _nextScene; _nextScene->retain(); _nextScene = nullptr ; if ((! runningIsTransition) && _runningScene) { _runningScene->onEnter(); _runningScene->onEnterTransitionDidFinish(); } } void Director::pause(){ if (_paused) { return ; } _oldAnimationInterval = _animationInterval; setAnimationInterval(1 / 4.0 ); _paused = true ; } void Director::resume(){ if (! _paused) { return ; } setAnimationInterval(_oldAnimationInterval); _paused = false ; _deltaTime = 0 ; setNextDeltaTimeZero(true ); }
关于runWithScene
,由于是开始第一个场景,所以,在入了场景栈之后就开始了Director的主循环。
然后pause
,将场景的帧数设置的很低,没有完全停止绘制
然后end
只是将一个_purgeDirectorInNextLoop
置为true,在下一帧的时候,就执行mainLoop中的清理函数,值得注意的是,清理函数purgeDirector的不会马上释放_scenesStack的内存,主要是因为有可能有人在end之后又调用runWithScene
关于_nextScene
和_runningScene
的关系,在下一帧的时候,_nextScene会被赋值给_runningScene,然后被置空,具体见drawScene和setNextScene
总结 有关于GLView的部分需要另外写一篇文章来讲,这里就不说了,然后Director的代码我也略去了与openGL相关的一些东西,这些东西留作以后补充。
其实看完Director的代码之后,很容易就可以知道从哪里去阅读Cocos2dx源码。
配置文件部分
渲染机制 – Render, RenderCommand…
时间分发机制 – EventDispatcher
动作管理 – ActionManager
GLView – openGL相关