diff --git a/core/Action/Action.cpp b/core/Action/Action.cpp
index 8ddd2cdb..24238d82 100644
--- a/core/Action/Action.cpp
+++ b/core/Action/Action.cpp
@@ -6,7 +6,6 @@ e2d::Action::Action()
 	, _done(false)
 	, _initialized(false)
 	, _target(nullptr)
-	, _last(0)
 {
 	ActionManager::getInstance()->__add(this);
 }
@@ -24,7 +23,6 @@ bool e2d::Action::isRunning()
 void e2d::Action::resume()
 {
 	_running = true;
-	_last = Game::getInstance()->getTotalDuration().seconds();
 }
 
 void e2d::Action::pause()
@@ -56,7 +54,7 @@ void e2d::Action::reset()
 {
 	_initialized = false;
 	_done = false;
-	_last = Game::getInstance()->getTotalDuration().seconds();
+	_started = Time::now();
 }
 
 bool e2d::Action::_isDone()
@@ -74,7 +72,7 @@ void e2d::Action::_startWithTarget(Node* target)
 void e2d::Action::_init()
 {
 	_initialized = true;
-	_last = Game::getInstance()->getTotalDuration().seconds();
+	_started = Time::now();
 }
 
 void e2d::Action::_update()
diff --git a/core/Action/Animate.cpp b/core/Action/Animate.cpp
index 61075af6..385b9b46 100644
--- a/core/Action/Animate.cpp
+++ b/core/Action/Animate.cpp
@@ -56,8 +56,7 @@ void e2d::Animate::_update()
 		return;
 	}
 
-	auto game = Game::getInstance();
-	while ((game->getTotalDuration().seconds() - _last) >= _animation->getInterval())
+	while ((Time::now() - _started).seconds() >= _animation->getInterval())
 	{
 		auto& frames = _animation->getFrames();
 		auto target = dynamic_cast<Sprite*>(_target);
@@ -67,7 +66,7 @@ void e2d::Animate::_update()
 			target->open(frames[_frameIndex]);
 		}
 
-		_last += _animation->getInterval();
+		_started += Duration(_animation->getInterval());
 		++_frameIndex;
 
 		if (_frameIndex == frames.size())
@@ -81,7 +80,6 @@ void e2d::Animate::_update()
 void e2d::Animate::_resetTime()
 {
 	Action::_resetTime();
-	_last = Game::getInstance()->getTotalDuration().seconds();
 }
 
 void e2d::Animate::reset()
diff --git a/core/Action/Delay.cpp b/core/Action/Delay.cpp
index 0198b65b..1f29436b 100644
--- a/core/Action/Delay.cpp
+++ b/core/Action/Delay.cpp
@@ -31,7 +31,7 @@ void e2d::Delay::_update()
 {
 	Action::_update();
 
-	_delta = Game::getInstance()->getTotalDuration().seconds() - _last;
+	_delta = (Time::now() - _started).seconds();
 
 	if (_delta >= _delay)
 	{
@@ -42,5 +42,5 @@ void e2d::Delay::_update()
 void e2d::Delay::_resetTime()
 {
 	Action::_resetTime();
-	_last = Game::getInstance()->getTotalDuration().seconds() - _delta;
+	_started = Time::now() - Duration(_delta);
 }
diff --git a/core/Action/FiniteTimeAction.cpp b/core/Action/FiniteTimeAction.cpp
index dd1fb98a..becd7b7c 100644
--- a/core/Action/FiniteTimeAction.cpp
+++ b/core/Action/FiniteTimeAction.cpp
@@ -28,7 +28,7 @@ void e2d::FiniteTimeAction::_update()
 	}
 	else
 	{
-		_delta = std::min((Game::getInstance()->getTotalDuration().seconds() - _last) / _duration, 1.f);
+		_delta = std::min((Time::now() - _started).seconds() / _duration, 1.f);
 
 		if (_delta >= 1)
 		{
@@ -40,5 +40,5 @@ void e2d::FiniteTimeAction::_update()
 void e2d::FiniteTimeAction::_resetTime()
 {
 	Action::_resetTime();
-	_last = Game::getInstance()->getTotalDuration().seconds() - _delta * _duration;
+	_started = Time::now() - Duration(_delta * _duration);
 }
diff --git a/core/Base/Game.cpp b/core/Base/Game.cpp
index 352129ec..4c7d80ca 100644
--- a/core/Base/Game.cpp
+++ b/core/Base/Game.cpp
@@ -12,8 +12,6 @@ e2d::Game::Game()
 	, _config()
 {
 	CoInitialize(nullptr);
-
-	_start = _last = _now = Time::now();
 }
 
 e2d::Game::~Game()
@@ -39,26 +37,25 @@ void e2d::Game::destroyInstance()
 
 void e2d::Game::start()
 {
-	SceneManager::getInstance()->update();
+	_quit = false;
 
+	const int minInterval = 5;
+	Time last = Time::now();
 	HWND hWnd = Window::getInstance()->getHWnd();
+	
 	::ShowWindow(hWnd, SW_SHOWNORMAL);
 	::UpdateWindow(hWnd);
 	Window::getInstance()->poll();
-
-	_quit = false;
-	_last = _now = Time::now();
-
-	const Duration minInterval(15);
+	SceneManager::getInstance()->update();
 	
 	while (!_quit)
 	{
-		_now = Time::now();
-		Duration interval = _now - _last;
+		auto now = Time::now();
+		auto dur = now - last;
 
-		if (minInterval < interval)
+		if (dur.milliseconds() > minInterval)
 		{
-			_last = _now;
+			last = now;
 			Input::getInstance()->update();
 			Timer::getInstance()->update();
 			ActionManager::getInstance()->update();
@@ -72,7 +69,7 @@ void e2d::Game::start()
 			// ID2D1HwndRenderTarget 在渲染时会等待显示器刷新，即开启了垂直同步，
 			// 它起到了非常稳定的延时作用，所以大部分时候不需要手动挂起线程进行延时。
 			// 下面的代码仅在一些情况下（例如窗口最小化时）挂起线程，防止占用过高 CPU 。
-			int wait = (minInterval - interval).milliseconds();
+			int wait = minInterval - dur.milliseconds();
 			if (wait > 1)
 			{
 				std::this_thread::sleep_for(std::chrono::milliseconds(wait));
@@ -90,7 +87,6 @@ void e2d::Game::resume()
 {
 	if (_paused && !_quit)
 	{
-		_last = _now = Time::now();
 		Timer::getInstance()->updateTime();
 		ActionManager::getInstance()->updateTime();
 	}
@@ -120,11 +116,6 @@ const e2d::Config& e2d::Game::getConfig()
 	return _config;
 }
 
-e2d::Duration e2d::Game::getTotalDuration() const
-{
-	return std::move(_now - _start);
-}
-
 void e2d::Game::quit()
 {
 	_quit = true;
diff --git a/core/Base/Renderer.cpp b/core/Base/Renderer.cpp
index 87b9f6cc..6d7e7369 100644
--- a/core/Base/Renderer.cpp
+++ b/core/Base/Renderer.cpp
@@ -107,15 +107,14 @@ void e2d::Renderer::render()
 
 void e2d::Renderer::_renderFps()
 {
-	++_renderTimes;
+	int duration = (Time::now() - _lastRenderTime).milliseconds();
 
-	auto& now = Time::now();
-	int duration = (now - _lastRenderTime).milliseconds();
+	++_renderTimes;
 	if (duration >= 100)
 	{
-		String fpsText = String::format(L"FPS: %.1f", (1000.f / duration * _renderTimes));
-		_renderTimes = 0;
-		_lastRenderTime = now;
+		String fpsText	= String::format(L"FPS: %.1f", (1000.f / duration * _renderTimes));
+		_lastRenderTime = Time::now();
+		_renderTimes	= 0;
 
 		auto writeFactory = Renderer::getWriteFactory();
 		if (!_fpsFormat)
diff --git a/core/Base/Window.cpp b/core/Base/Window.cpp
index 43585eff..dd525cab 100644
--- a/core/Base/Window.cpp
+++ b/core/Base/Window.cpp
@@ -3,6 +3,9 @@
 #include <imm.h>
 #pragma comment (lib ,"imm32.lib")
 
+#define WINDOW_STYLE	WS_OVERLAPPEDWINDOW & ~WS_MAXIMIZEBOX & ~WS_THICKFRAME
+#define REGISTER_CLASS	L"Easy2DApp"
+
 
 e2d::Window * e2d::Window::_instance = nullptr;
 
@@ -51,9 +54,7 @@ bool e2d::Window::createMutex(const String & mutex)
 	if (mutex.isEmpty())
 		return false;
 
-	// 创建进程互斥体
-	String fullMutexName = L"Easy2DApp-" + mutex;
-	HANDLE hMutex = ::CreateMutex(nullptr, TRUE, (LPCWSTR)fullMutexName);
+	HANDLE hMutex = ::CreateMutex(nullptr, TRUE, LPCWSTR(L"Easy2DApp-" + mutex));
 
 	if (hMutex == nullptr)
 	{
@@ -68,7 +69,7 @@ bool e2d::Window::createMutex(const String & mutex)
 		if (!this->_title.isEmpty())
 		{
 			// 获取窗口句柄
-			HWND hProgramWnd = ::FindWindow(L"Easy2DApp", (LPCTSTR)this->_title);
+			HWND hProgramWnd = ::FindWindow(REGISTER_CLASS, (LPCTSTR)_title);
 			if (hProgramWnd)
 			{
 				// 获取窗口显示状态
@@ -85,79 +86,59 @@ bool e2d::Window::createMutex(const String & mutex)
 	return true;
 }
 
-HWND e2d::Window::__create()
+HWND e2d::Window::__registerWindow()
 {
-	// 注册窗口类
 	WNDCLASSEX wcex = { 0 };
-	wcex.cbSize = sizeof(WNDCLASSEX);
-	wcex.lpszClassName = L"Easy2DApp";
-	wcex.style = CS_HREDRAW | CS_VREDRAW | CS_DBLCLKS;
-	wcex.lpfnWndProc = Window::WndProc;
-	wcex.cbClsExtra = 0;
-	wcex.cbWndExtra = sizeof(LONG_PTR);
-	wcex.hInstance = HINST_THISCOMPONENT;
-	wcex.hbrBackground = nullptr;
-	wcex.lpszMenuName = nullptr;
-	wcex.hCursor = ::LoadCursor(nullptr, IDC_ARROW);
+	wcex.cbSize			= sizeof(WNDCLASSEX);
+	wcex.lpszClassName	= REGISTER_CLASS;
+	wcex.style			= CS_HREDRAW | CS_VREDRAW | CS_DBLCLKS;
+	wcex.lpfnWndProc	= Window::WndProc;
+	wcex.hIcon			= nullptr;
+	wcex.cbClsExtra		= 0;
+	wcex.cbWndExtra		= sizeof(LONG_PTR);
+	wcex.hInstance		= HINST_THISCOMPONENT;
+	wcex.hbrBackground	= nullptr;
+	wcex.lpszMenuName	= nullptr;
+	wcex.hCursor		= ::LoadCursor(nullptr, IDC_ARROW);
 
-	if (this->_iconID != 0)
+	if (_iconID != 0)
 	{
 		wcex.hIcon = (HICON)::LoadImage(
 			HINST_THISCOMPONENT,
-			MAKEINTRESOURCE(this->_iconID),
+			MAKEINTRESOURCE(_iconID),
 			IMAGE_ICON,
 			0,
 			0,
 			LR_DEFAULTCOLOR | LR_CREATEDIBSECTION | LR_DEFAULTSIZE
 		);
 	}
-	else
-	{
-		wcex.hIcon = nullptr;
-	}
 
+	// 注册窗口类
 	RegisterClassEx(&wcex);
 
-	// 因为 CreateWindow 函数使用的是像素大小，获取系统的 DPI 以使它
-	// 适应窗口缩放
-	float dpiScaleX = 0.f, dpiScaleY = 0.f;
-	Renderer::getFactory()->GetDesktopDpi(&dpiScaleX, &dpiScaleY);
-
-	int nWidth = static_cast<int>(ceil(_size.width * dpiScaleX / 96.f));
-	int nHeight = static_cast<int>(ceil(_size.height * dpiScaleY / 96.f));
-
 	// 计算窗口大小
-	DWORD dwStyle = WS_OVERLAPPEDWINDOW & ~WS_MAXIMIZEBOX & ~WS_THICKFRAME;
-	RECT wr = { 0, 0, static_cast<LONG>(nWidth), static_cast<LONG>(nHeight) };
-	::AdjustWindowRectEx(&wr, dwStyle, FALSE, NULL);
-	// 获取新的宽高
-	nWidth = static_cast<int>(wr.right - wr.left);
-	nHeight = static_cast<int>(wr.bottom - wr.top);
-
-	// 获取屏幕分辨率
-	int screenWidth = ::GetSystemMetrics(SM_CXSCREEN);
-	int screenHeight = ::GetSystemMetrics(SM_CYSCREEN);
+	Rect wRect = __adjustWindow(int(_size.width), int(_size.height));
 
 	// 创建窗口
 	HWND hWnd = ::CreateWindowEx(
 		NULL,
-		L"Easy2DApp",
+		REGISTER_CLASS,
 		(LPCTSTR)_title,
-		dwStyle,
-		(screenWidth - nWidth) / 2, (screenHeight - nHeight) / 2,
-		nWidth, nHeight,
+		WINDOW_STYLE,
+		int(wRect.origin.x),
+		int(wRect.origin.y),
+		int(wRect.size.width),
+		int(wRect.size.height),
 		nullptr,
 		nullptr,
 		HINST_THISCOMPONENT,
 		nullptr
 	);
 
-	HRESULT hr = hWnd ? S_OK : E_FAIL;
-
-	if (SUCCEEDED(hr))
+	if (hWnd)
 	{
 		// 禁用输入法
-		this->setTypewritingEnabled(false);
+		setTypewritingEnabled(false);
 		// 禁用控制台关闭按钮
 		HWND consoleHWnd = ::GetConsoleWindow();
 		if (consoleHWnd)
@@ -170,11 +151,35 @@ HWND e2d::Window::__create()
 	}
 	else
 	{
-		::UnregisterClass(L"Easy2DApp", HINST_THISCOMPONENT);
+		::UnregisterClass(REGISTER_CLASS, HINST_THISCOMPONENT);
 	}
 	return hWnd;
 }
 
+e2d::Rect e2d::Window::__adjustWindow(int width, int height)
+{
+	float dpiScaleX = 0.f, dpiScaleY = 0.f;
+	Renderer::getFactory()->GetDesktopDpi(&dpiScaleX, &dpiScaleY);
+
+	Rect result;
+	RECT wRECT		= { 0, 0, LONG(ceil(width * dpiScaleX / 96.f)), LONG(ceil(height * dpiScaleY / 96.f)) };
+	int maxWidth	= ::GetSystemMetrics(SM_CXSCREEN);
+	int maxHeight	= ::GetSystemMetrics(SM_CYSCREEN);
+
+	// 计算合适的窗口大小
+	::AdjustWindowRectEx(&wRECT, WINDOW_STYLE, FALSE, NULL);
+	width = static_cast<int>(wRECT.right - wRECT.left);
+	height = static_cast<int>(wRECT.bottom - wRECT.top);
+
+	// 当输入的窗口大小比分辨率大时，给出警告
+	WARN_IF(maxWidth < width || maxHeight < height, "The window is larger than screen!");
+	width = std::min(width, maxWidth);
+	height = std::min(height, maxHeight);
+
+	float x = float((maxWidth - width) / 2), y = float((maxHeight - height) / 2);
+	return std::move(Rect(x, y, float(width), float(height)));
+}
+
 void e2d::Window::poll()
 {
 	while (::PeekMessage(&_msg, nullptr, 0, 0, PM_REMOVE))
@@ -213,7 +218,7 @@ HWND e2d::Window::getHWnd()
 {
 	if (!_hWnd)
 	{
-		_hWnd = this->__create();
+		_hWnd = __registerWindow();
 		if (_hWnd == nullptr)
 		{
 			throw SystemException(L"注册窗口失败");
@@ -224,37 +229,24 @@ HWND e2d::Window::getHWnd()
 
 void e2d::Window::setSize(int width, int height)
 {
-	this->_size = Size(static_cast<float>(width), static_cast<float>(height));
+	_size = Size(static_cast<float>(width), static_cast<float>(height));
 	if (_hWnd)
 	{
-		float dpiScaleX = 0.f, dpiScaleY = 0.f;
-		Renderer::getFactory()->GetDesktopDpi(&dpiScaleX, &dpiScaleY);
-
-		width = static_cast<int>(ceil(width * dpiScaleX / 96.f));
-		height = static_cast<int>(ceil(height * dpiScaleY / 96.f));
-		// 计算窗口大小
-		DWORD dwStyle = WS_OVERLAPPEDWINDOW & ~WS_MAXIMIZEBOX & ~WS_THICKFRAME;
-		RECT wr = { 0, 0, static_cast<LONG>(width), static_cast<LONG>(height) };
-		::AdjustWindowRectEx(&wr, dwStyle, FALSE, NULL);
-		// 获取新的宽高
-		width = static_cast<int>(wr.right - wr.left);
-		height = static_cast<int>(wr.bottom - wr.top);
-		// 获取屏幕分辨率
-		int screenWidth = ::GetSystemMetrics(SM_CXSCREEN);
-		int screenHeight = ::GetSystemMetrics(SM_CYSCREEN);
-		// 当输入的窗口大小比分辨率大时，给出警告
-		WARN_IF(screenWidth < width || screenHeight < height, "The window is larger than screen!");
-		// 取最小值
-		width = std::min(width, screenWidth);
-		height = std::min(height, screenHeight);
-		// 修改窗口大小，并设置窗口在屏幕居中
-		::MoveWindow(_hWnd, (screenWidth - width) / 2, (screenHeight - height) / 2, width, height, TRUE);
+		Rect wRect = __adjustWindow(width, height);
+		::MoveWindow(
+			_hWnd,
+			int(wRect.origin.x),
+			int(wRect.origin.y),
+			int(wRect.size.width),
+			int(wRect.size.height),
+			TRUE
+		);
 	}
 }
 
 void e2d::Window::setTitle(const String& title)
 {
-	this->_title = title;
+	_title = title;
 	if (_hWnd)
 	{
 		::SetWindowText(_hWnd, (LPCWSTR)title);
diff --git a/core/Common/Duration.cpp b/core/Common/Duration.cpp
index 0e672f65..94a27ac5 100644
--- a/core/Common/Duration.cpp
+++ b/core/Common/Duration.cpp
@@ -7,13 +7,8 @@ e2d::Duration::Duration()
 {
 }
 
-e2d::Duration::Duration(int ms)
-	: _ms(ms)
-{
-}
-
-e2d::Duration::Duration(const std::chrono::milliseconds& ms)
-	: _ms(ms)
+e2d::Duration::Duration(float seconds)
+	: _ms(static_cast<long long>(seconds * 1000.f))
 {
 }
 
@@ -59,12 +54,16 @@ bool e2d::Duration::operator<=(const Duration & other) const
 
 e2d::Duration e2d::Duration::operator+(Duration const & other) const
 {
-	return std::move(Duration(_ms + other._ms));
+	Duration d;
+	d._ms = _ms + other._ms;
+	return std::move(d);
 }
 
 e2d::Duration e2d::Duration::operator-(Duration const & other) const
 {
-	return std::move(Duration(_ms - other._ms));
+	Duration d;
+	d._ms = _ms - other._ms;
+	return std::move(d);
 }
 
 e2d::Duration & e2d::Duration::operator+=(Duration const &other)
diff --git a/core/Common/Time.cpp b/core/Common/Time.cpp
index 6a2bfc4d..a709e5ad 100644
--- a/core/Common/Time.cpp
+++ b/core/Common/Time.cpp
@@ -7,11 +7,6 @@ e2d::Time::Time()
 {
 }
 
-e2d::Time::Time(const steady_clock::time_point& time)
-	: _timePoint(time)
-{
-}
-
 time_t e2d::Time::getTimeStamp() const
 {
 	auto& duration = time_point_cast<milliseconds>(_timePoint).time_since_epoch();
@@ -25,7 +20,16 @@ bool e2d::Time::isZero() const
 
 e2d::Time e2d::Time::operator+(Duration const & other) const
 {
-	return std::move(Time(_timePoint + milliseconds(other.milliseconds())));
+	Time t;
+	t._timePoint = _timePoint + milliseconds(other.milliseconds());
+	return std::move(t);
+}
+
+e2d::Time e2d::Time::operator-(Duration const & other) const
+{
+	Time t;
+	t._timePoint = _timePoint - milliseconds(other.milliseconds());
+	return std::move(t);
 }
 
 e2d::Time & e2d::Time::operator+=(Duration const & other)
@@ -34,11 +38,6 @@ e2d::Time & e2d::Time::operator+=(Duration const & other)
 	return (*this);
 }
 
-e2d::Time e2d::Time::operator-(Duration const & other) const
-{
-	return std::move(Time(_timePoint - milliseconds(other.milliseconds())));
-}
-
 e2d::Time & e2d::Time::operator-=(Duration const &other)
 {
 	_timePoint -= milliseconds(other.milliseconds());
@@ -47,11 +46,13 @@ e2d::Time & e2d::Time::operator-=(Duration const &other)
 
 e2d::Duration e2d::Time::operator-(Time const & other) const
 {
-	auto& ms = duration_cast<milliseconds>(_timePoint - other._timePoint);
-	return std::move(Duration(ms));
+	auto ms = duration_cast<milliseconds>(_timePoint - other._timePoint).count();
+	return std::move(Duration(static_cast<float>(ms) / 1000.f));
 }
 
 e2d::Time e2d::Time::now()
 {
-	return std::move(Time(steady_clock::now()));
+	Time t;
+	t._timePoint = steady_clock::now();
+	return std::move(t);
 }
diff --git a/core/Manager/SceneManager.cpp b/core/Manager/SceneManager.cpp
index 7363e499..d4a5f005 100644
--- a/core/Manager/SceneManager.cpp
+++ b/core/Manager/SceneManager.cpp
@@ -22,8 +22,7 @@ void e2d::SceneManager::destroyInstance()
 }
 
 e2d::SceneManager::SceneManager()
-	: _saveCurrScene(true)
-	, _currScene(nullptr)
+	: _currScene(nullptr)
 	, _nextScene(nullptr)
 	, _transition(nullptr)
 	, _scenes()
@@ -34,7 +33,7 @@ e2d::SceneManager::~SceneManager()
 {
 }
 
-void e2d::SceneManager::push(Scene * scene, Transition * transition /* = nullptr */, bool saveCurrentScene /* = true */)
+void e2d::SceneManager::push(Scene * scene, bool saveCurrentScene)
 {
 	if (!scene)
 		return;
@@ -44,58 +43,59 @@ void e2d::SceneManager::push(Scene * scene, Transition * transition /* = nullptr
 	_nextScene = scene;
 	_nextScene->retain();
 	
-	// 设置切换场景动作
-	if (transition)
+	// 初始化场景切换动画
+	if (_transition && !_transition->init(_currScene, _nextScene))
 	{
-		if (_transition)
-		{
-			_transition->_stop();
-			_transition->release();
-		}
-		_transition = transition;
-		transition->retain();
-		transition->_init(_currScene, _nextScene);
-		transition->_update();
+		WARN("Transition initialize failed!");
+		_transition->release();
+		_transition = nullptr;
 	}
 
-	if (_currScene)
+	if (saveCurrentScene && _currScene)
 	{
-		_saveCurrScene = saveCurrentScene;
+		_scenes.push(_currScene);
 	}
 }
 
-void e2d::SceneManager::pop(Transition * transition /* = nullptr */)
+e2d::Scene* e2d::SceneManager::pop()
 {
 	// 栈为空时，调用返回场景函数失败
 	if (_scenes.size() == 0)
 	{
 		WARN("Scene stack is empty!");
-		return;
+		return nullptr;
 	}
 
-	// 从栈顶取出场景指针，作为下一场景
 	_nextScene = _scenes.top();
 	_scenes.pop();
 
-	// 返回上一场景时，不保存当前场景
-	if (_currScene)
+	// 初始化场景切换动画
+	if (_transition && !_transition->init(_currScene, _nextScene))
 	{
-		_saveCurrScene = false;
+		WARN("Transition initialize failed!");
+		_transition->release();
+		_transition = nullptr;
 	}
 
-	// 设置切换场景动作
+	return _nextScene;
+}
+
+void e2d::SceneManager::setTransition(Transition * transition)
+{
 	if (transition)
 	{
-		transition->retain();
-		transition->_init(_currScene, _nextScene);
-		transition->_update();
+		if (_transition)
+		{
+			_transition->stop();
+			_transition->release();
+		}
 		_transition = transition;
+		_transition->retain();
 	}
 }
 
 void e2d::SceneManager::clear()
 {
-	// 清空场景栈
 	while (!_scenes.empty())
 	{
 		_scenes.top()->release();
@@ -108,7 +108,7 @@ e2d::Scene * e2d::SceneManager::getCurrentScene()
 	return _currScene;
 }
 
-std::stack<e2d::Scene*> e2d::SceneManager::getSceneStack()
+const std::stack<e2d::Scene*>& e2d::SceneManager::getSceneStack()
 {
 	return _scenes;
 }
@@ -120,19 +120,13 @@ bool e2d::SceneManager::isTransitioning()
 
 void e2d::SceneManager::update()
 {
-	if (_transition == nullptr)
-	{
-		// 更新场景内容
-		if (_currScene)
-		{
-			_currScene->update();
-		}
-	}
-	else
-	{
-		// 更新场景动作
-		_transition->_update();
+	if (_currScene) _currScene->update();
+	if (_nextScene) _nextScene->update();
 
+	if (_transition)
+	{
+		_transition->update();
+		
 		if (_transition->isDone())
 		{
 			_transition->release();
@@ -144,26 +138,17 @@ void e2d::SceneManager::update()
 		}
 	}
 
-	// 下一场景指针不为空时，切换场景
 	if (_nextScene)
 	{
 		if (_currScene)
 		{
-			// 执行当前场景的 onExit 函数
 			_currScene->onExit();
-
-			// 若要保存当前场景，把它放入栈中
-			if (_saveCurrScene)
-			{
-				_scenes.push(_currScene);
-			}
-			else
+			if (_scenes.empty() || _scenes.top() != _currScene)
 			{
 				_currScene->release();
 			}
 		}
 
-		// 执行下一场景的 onEnter 函数
 		_nextScene->onEnter();
 
 		_currScene = _nextScene;
@@ -175,15 +160,11 @@ void e2d::SceneManager::render()
 {
 	if (_transition)
 	{
-		_transition->_render();
+		_transition->render();
 	}
-	else
+	else if (_currScene)
 	{
-		// 绘制当前场景
-		if (_currScene)
-		{
-			_currScene->render();
-		}
+		_currScene->render();
 	}
 }
 
diff --git a/core/Tool/Task.cpp b/core/Tool/Task.cpp
index 206bf5f5..1d1984e4 100644
--- a/core/Tool/Task.cpp
+++ b/core/Tool/Task.cpp
@@ -6,8 +6,7 @@ e2d::Task::Task(const Function & func, const String & name)
 	, _stopped(false)
 	, _runTimes(0)
 	, _totalTimes(-1)
-	, _delay(0.f)
-	, _lastTime(0.f)
+	, _delay()
 	, _callback(func)
 	, _name(name)
 {
@@ -17,9 +16,8 @@ e2d::Task::Task(const Function & func, float delay, int times, const String & na
 	: _running(true)
 	, _stopped(false)
 	, _runTimes(0)
-	, _totalTimes(times)
 	, _delay(std::max(delay, 0.f))
-	, _lastTime(0.f)
+	, _totalTimes(times)
 	, _callback(func)
 	, _name(name)
 {
@@ -38,17 +36,24 @@ void e2d::Task::resume()
 
 void e2d::Task::update()
 {
-	if (_callback)
+	if (_totalTimes == 0)
 	{
-		_callback();
+		_stopped = true;
+		return;
 	}
 
 	++_runTimes;
 	_lastTime += _delay;
 
+	if (_callback)
+	{
+		_callback();
+	}
+
 	if (_runTimes == _totalTimes)
 	{
 		_stopped = true;
+		return;
 	}
 }
 
@@ -56,11 +61,11 @@ bool e2d::Task::isReady() const
 {
 	if (_running)
 	{
-		if (_delay == 0)
+		if (_delay.milliseconds() == 0)
 		{
 			return true;
 		}
-		if ((Game::getInstance()->getTotalDuration().seconds() - _lastTime) >= _delay)
+		if (Time::now() - _lastTime >= _delay)
 		{
 			return true;
 		}
@@ -80,5 +85,5 @@ e2d::String e2d::Task::getName() const
 
 void e2d::Task::updateTime()
 {
-	_lastTime = Game::getInstance()->getTotalDuration().seconds();
-}
\ No newline at end of file
+	_lastTime = Time::now();
+}
diff --git a/core/Transition/BoxTransition.cpp b/core/Transition/BoxTransition.cpp
index 885093e6..641e6a1d 100644
--- a/core/Transition/BoxTransition.cpp
+++ b/core/Transition/BoxTransition.cpp
@@ -6,14 +6,20 @@ e2d::BoxTransition::BoxTransition(float duration)
 {
 }
 
-void e2d::BoxTransition::_init(Scene * prev, Scene * next)
+bool e2d::BoxTransition::init(Scene * prev, Scene * next)
 {
-	Transition::_init(prev, next);
-	_inLayerParam.opacity = 0;
+	if (Transition::init(prev, next))
+	{
+		_inLayerParam.opacity = 0;
+		return true;
+	}
+	return false;
 }
 
-void e2d::BoxTransition::_updateCustom()
+void e2d::BoxTransition::update()
 {
+	Transition::update();
+
 	if (_delta <= 0.5)
 	{
 		_outLayerParam.contentBounds = D2D1::RectF(
@@ -35,11 +41,11 @@ void e2d::BoxTransition::_updateCustom()
 		);
 		if (_delta >= 1)
 		{
-			this->_stop();
+			this->stop();
 		}
 	}
 }
 
-void e2d::BoxTransition::_reset()
+void e2d::BoxTransition::reset()
 {
 }
diff --git a/core/Transition/EmergeTransition.cpp b/core/Transition/EmergeTransition.cpp
index 6bd7c819..c79d8f5a 100644
--- a/core/Transition/EmergeTransition.cpp
+++ b/core/Transition/EmergeTransition.cpp
@@ -6,24 +6,30 @@ e2d::EmergeTransition::EmergeTransition(float duration)
 {
 }
 
-void e2d::EmergeTransition::_init(Scene * prev, Scene * next)
+bool e2d::EmergeTransition::init(Scene * prev, Scene * next)
 {
-	Transition::_init(prev, next);
-	_outLayerParam.opacity = 1;
-	_inLayerParam.opacity = 0;
+	if (Transition::init(prev, next))
+	{
+		_outLayerParam.opacity = 1;
+		_inLayerParam.opacity = 0;
+		return true;
+	}
+	return false;
 }
 
-void e2d::EmergeTransition::_updateCustom()
+void e2d::EmergeTransition::update()
 {
+	Transition::update();
+
 	_outLayerParam.opacity = 1 - _delta;
 	_inLayerParam.opacity = _delta;
 
 	if (_delta >= 1)
 	{
-		this->_stop();
+		this->stop();
 	}
 }
 
-void e2d::EmergeTransition::_reset()
+void e2d::EmergeTransition::reset()
 {
 }
diff --git a/core/Transition/FadeTransition.cpp b/core/Transition/FadeTransition.cpp
index 4a49ed2f..459e0b9f 100644
--- a/core/Transition/FadeTransition.cpp
+++ b/core/Transition/FadeTransition.cpp
@@ -6,15 +6,21 @@ e2d::FadeTransition::FadeTransition(float duration)
 {
 }
 
-void e2d::FadeTransition::_init(Scene * prev, Scene * next)
+bool e2d::FadeTransition::init(Scene * prev, Scene * next)
 {
-	Transition::_init(prev, next);
-	_outLayerParam.opacity = 1;
-	_inLayerParam.opacity = 0;
+	if (Transition::init(prev, next))
+	{
+		_outLayerParam.opacity = 1;
+		_inLayerParam.opacity = 0;
+		return true;
+	}
+	return false;
 }
 
-void e2d::FadeTransition::_updateCustom()
+void e2d::FadeTransition::update()
 {
+	Transition::update();
+
 	if (_delta < 0.5)
 	{
 		_outLayerParam.opacity = 1 - _delta * 2;
@@ -26,11 +32,11 @@ void e2d::FadeTransition::_updateCustom()
 		_inLayerParam.opacity = (_delta - 0.5f) * 2;
 		if (_delta >= 1)
 		{
-			this->_stop();
+			this->stop();
 		}
 	}
 }
 
-void e2d::FadeTransition::_reset()
+void e2d::FadeTransition::reset()
 {
 }
diff --git a/core/Transition/MoveTransition.cpp b/core/Transition/MoveTransition.cpp
index 168b6356..76e07495 100644
--- a/core/Transition/MoveTransition.cpp
+++ b/core/Transition/MoveTransition.cpp
@@ -7,39 +7,44 @@ e2d::MoveTransition::MoveTransition(float duration, Direction direction)
 {
 }
 
-void e2d::MoveTransition::_init(Scene * prev, Scene * next)
+bool e2d::MoveTransition::init(Scene * prev, Scene * next)
 {
-	Transition::_init(prev, next);
+	if (Transition::init(prev, next))
+	{
+		float width = _windowSize.width;
+		float height = _windowSize.height;
+		if (_direction == Direction::Up)
+		{
+			_posDelta = Vector2(0, -height);
+			_startPos = Point(0, height);
+		}
+		else if (_direction == Direction::Down)
+		{
+			_posDelta = Vector2(0, height);
+			_startPos = Point(0, -height);
+		}
+		else if (_direction == Direction::Left)
+		{
+			_posDelta = Vector2(-width, 0);
+			_startPos = Point(width, 0);
+		}
+		else if (_direction == Direction::Right)
+		{
+			_posDelta = Vector2(width, 0);
+			_startPos = Point(-width, 0);
+		}
 
-	float width = _windowSize.width;
-	float height = _windowSize.height;
-	if (_direction == Direction::Up)
-	{
-		_posDelta = Vector2(0, -height);
-		_startPos = Point(0, height);
+		if (_outScene) _outScene->getRoot()->setPos(0, 0);
+		_inScene->getRoot()->setPos(_startPos);
+		return true;
 	}
-	else if (_direction == Direction::Down)
-	{
-		_posDelta = Vector2(0, height);
-		_startPos = Point(0, -height);
-	}
-	else if (_direction == Direction::Left)
-	{
-		_posDelta = Vector2(-width, 0);
-		_startPos = Point(width, 0);
-	}
-	else if (_direction == Direction::Right)
-	{
-		_posDelta = Vector2(width, 0);
-		_startPos = Point(-width, 0);
-	}
-
-	if (_outScene) _outScene->getRoot()->setPos(0, 0);
-	_inScene->getRoot()->setPos(_startPos);
+	return false;
 }
 
-void e2d::MoveTransition::_updateCustom()
+void e2d::MoveTransition::update()
 {
+	Transition::update();
+
 	if (_outScene)
 	{
 		_outScene->getRoot()->setPos(_posDelta * _delta);
@@ -51,11 +56,11 @@ void e2d::MoveTransition::_updateCustom()
 
 	if (_delta >= 1)
 	{
-		this->_stop();
+		this->stop();
 	}
 }
 
-void e2d::MoveTransition::_reset()
+void e2d::MoveTransition::reset()
 {
 	if (_outScene) _outScene->getRoot()->setPos(0, 0);
 	_inScene->getRoot()->setPos(0, 0);
diff --git a/core/Transition/Transition.cpp b/core/Transition/Transition.cpp
index 04e0c810..b487f316 100644
--- a/core/Transition/Transition.cpp
+++ b/core/Transition/Transition.cpp
@@ -4,7 +4,7 @@
 
 e2d::Transition::Transition(float duration)
 	: _end(false)
-	, _last()
+	, _started()
 	, _delta(0)
 	, _outScene(nullptr)
 	, _inScene(nullptr)
@@ -29,7 +29,7 @@ bool e2d::Transition::isDone()
 	return _end;
 }
 
-void e2d::Transition::_init(Scene * prev, Scene * next)
+bool e2d::Transition::init(Scene * prev, Scene * next)
 {
 	auto renderer = Renderer::getInstance();
 	// 创建图层
@@ -42,10 +42,10 @@ void e2d::Transition::_init(Scene * prev, Scene * next)
 
 	if (FAILED(hr))
 	{
-		throw SystemException(L"场景过渡动画图层创建失败");
+		return false;
 	}
 
-	_last = Game::getInstance()->getTotalDuration();
+	_started = Time::now();
 	_outScene = prev;
 	_inScene = next;
 	if (_outScene) _outScene->retain();
@@ -61,35 +61,24 @@ void e2d::Transition::_init(Scene * prev, Scene * next)
 		renderer->getSolidColorBrush(),
 		D2D1_LAYER_OPTIONS_NONE
 	);
+
+	return true;
 }
 
-void e2d::Transition::_update()
+void e2d::Transition::update()
 {
-	// 计算动作进度
 	if (_duration == 0)
 	{
 		_delta = 1;
 	}
 	else
 	{
-		_delta = (Game::getInstance()->getTotalDuration() - _last).seconds() / _duration;
+		_delta = (Time::now() - _started).seconds() / _duration;
 		_delta = std::min(_delta, 1.f);
 	}
-
-	this->_updateCustom();
-
-	// 更新场景内容
-	if (_outScene)
-	{
-		_outScene->update();
-	}
-	if (_inScene)
-	{
-		_inScene->update();
-	}
 }
 
-void e2d::Transition::_render()
+void e2d::Transition::render()
 {
 	auto pRT = Renderer::getInstance()->getRenderTarget();
 
@@ -132,8 +121,8 @@ void e2d::Transition::_render()
 	}
 }
 
-void e2d::Transition::_stop()
+void e2d::Transition::stop()
 {
 	_end = true;
-	_reset();
+	reset();
 }
diff --git a/core/e2daction.h b/core/e2daction.h
index fbc99898..fa6352db 100644
--- a/core/e2daction.h
+++ b/core/e2daction.h
@@ -85,7 +85,7 @@ protected:
 	bool	_done;
 	bool	_initialized;
 	Node *	_target;
-	float	_last;
+	Time	_started;
 };
 
 
diff --git a/core/e2dbase.h b/core/e2dbase.h
index eae663a2..2764b0b6 100644
--- a/core/e2dbase.h
+++ b/core/e2dbase.h
@@ -118,9 +118,6 @@ public:
 	// 获取游戏配置
 	const Config& getConfig();
 
-	// 获取游戏总时长
-	Duration getTotalDuration() const;
-
 private:
 	Game();
 
@@ -132,9 +129,6 @@ private:
 	bool		_quit;
 	bool		_paused;
 	Config		_config;
-	Time		_start;
-	Time		_now;
-	Time		_last;
 
 	static Game * _instance;
 };
@@ -243,7 +237,13 @@ private:
 	E2D_DISABLE_COPY(Window);
 
 	// 注册窗口
-	HWND __create();
+	HWND __registerWindow();
+
+	// 根据客户区大小计算合适的窗口区域
+	Rect __adjustWindow(
+		int width,
+		int height
+	);
 
 	// Win32 窗口消息回调程序
 	static LRESULT CALLBACK WndProc(
@@ -342,12 +342,6 @@ public:
 		Color color
 	);
 
-	// 渲染游戏画面
-	void render();
-
-	// 删除设备相关资源
-	void discardDeviceResources();
-
 	// 获取文字渲染器
 	TextRenderer * getTextRenderer();
 
@@ -357,6 +351,12 @@ public:
 	// 获取 ID2D1SolidColorBrush 对象
 	ID2D1SolidColorBrush * getSolidColorBrush();
 
+	// 渲染游戏画面
+	void render();
+
+	// 删除设备相关资源
+	void discardDeviceResources();
+
 	// 获取 ID2D1Factory 对象
 	static ID2D1Factory * getFactory();
 
diff --git a/core/e2dcommon.h b/core/e2dcommon.h
index 7aeda3bd..9ebe3c44 100644
--- a/core/e2dcommon.h
+++ b/core/e2dcommon.h
@@ -414,11 +414,7 @@ public:
 	Duration();
 
 	explicit Duration(
-		int ms
-	);
-
-	explicit Duration(
-		const std::chrono::milliseconds& ms
+		float seconds
 	);
 
 	// 获取毫秒数
@@ -451,10 +447,6 @@ class Time
 public:
 	Time();
 
-	explicit Time(
-		const std::chrono::steady_clock::time_point& time
-	);
-
 	// 获取时间戳
 	time_t getTimeStamp() const;
 
diff --git a/core/e2dmanager.h b/core/e2dmanager.h
index 0ca20a4b..1fe957ee 100644
--- a/core/e2dmanager.h
+++ b/core/e2dmanager.h
@@ -25,13 +25,15 @@ public:
 	// 场景入栈
 	void push(
 		Scene * scene,						/* 下一个场景的指针 */
-		Transition * transition = nullptr,	/* 场景切换动作 */
 		bool saveCurrentScene = true		/* 是否保存当前场景 */
 	);
 
 	// 场景出栈
-	void pop(
-		Transition * transition = nullptr	/* 场景切换动作 */
+	Scene* pop();
+
+	// 设置场景切换动作
+	void setTransition(
+		Transition * transition	/* 场景切换动作 */
 	);
 
 	// 清空保存的所有场景
@@ -41,7 +43,7 @@ public:
 	Scene * getCurrentScene();
 
 	// 获取场景栈
-	std::stack<Scene*> getSceneStack();
+	const std::stack<Scene*>& getSceneStack();
 
 	// 是否正在进行转场动作
 	bool isTransitioning();
@@ -70,7 +72,6 @@ private:
 	E2D_DISABLE_COPY(SceneManager);
 
 private:
-	bool				_saveCurrScene;
 	Scene *				_currScene;
 	Scene *				_nextScene;
 	Transition *		_transition;
diff --git a/core/e2dtool.h b/core/e2dtool.h
index 1b3f3ad8..9c8b52be 100644
--- a/core/e2dtool.h
+++ b/core/e2dtool.h
@@ -308,8 +308,8 @@ private:
 	bool		_stopped;
 	int			_runTimes;
 	int			_totalTimes;
-	float		_delay;
-	float		_lastTime;
+	Duration	_delay;
+	Time		_lastTime;
 	String		_name;
 	Function	_callback;
 };
diff --git a/core/e2dtransition.h b/core/e2dtransition.h
index bbf8fb88..0d94a451 100644
--- a/core/e2dtransition.h
+++ b/core/e2dtransition.h
@@ -5,15 +5,10 @@ namespace e2d
 {
 
 
-class SceneManager;
-
-
 // 场景过渡
 class Transition :
 	public Ref
 {
-	friend class SceneManager;
-
 public:
 	explicit Transition(float duration);
 
@@ -22,36 +17,32 @@ public:
 	// 场景过渡动画是否结束
 	bool isDone();
 
-protected:
 	// 初始化场景过渡动画
-	virtual void _init(
+	virtual bool init(
 		Scene * prev,
 		Scene * next
 	);
 
 	// 更新场景过渡动画
-	virtual void _update();
-
-	// 更新场景过渡动画
-	virtual void _updateCustom() = 0;
+	virtual void update();
 
 	// 渲染场景过渡动画
-	virtual void _render();
-
-	// 重置场景过渡动画
-	virtual void _reset() = 0;
+	virtual void render();
 
 	// 停止场景过渡动画
-	virtual void _stop();
+	virtual void stop();
+
+	// 重置场景过渡动画
+	virtual void reset() = 0;
 
 protected:
-	bool _end;
-	float _duration;
-	float _delta;
-	Duration _last;
-	Size _windowSize;
-	Scene * _outScene;
-	Scene * _inScene;
+	bool	_end;
+	float	_duration;
+	float	_delta;
+	Time	_started;
+	Size	_windowSize;
+	Scene*	_outScene;
+	Scene*	_inScene;
 	ID2D1Layer * _outLayer;
 	ID2D1Layer * _inLayer;
 	D2D1_LAYER_PARAMETERS _outLayerParam;
@@ -68,16 +59,15 @@ public:
 		float duration	/* 动画持续时长 */
 	);
 
-protected:
 	// 更新动画
-	virtual void _updateCustom() override;
+	virtual void update() override;
 
-	virtual void _init(
+	virtual bool init(
 		Scene * prev,
 		Scene * next
 	) override;
 
-	virtual void _reset() override;
+	virtual void reset() override;
 };
 
 
@@ -90,16 +80,15 @@ public:
 		float duration	/* 浮现动画持续时长 */
 	);
 
-protected:
 	// 更新动画
-	virtual void _updateCustom() override;
+	virtual void update() override;
 
-	virtual void _init(
+	virtual bool init(
 		Scene * prev,
 		Scene * next
 	) override;
 
-	virtual void _reset() override;
+	virtual void reset() override;
 };
 
 
@@ -112,16 +101,15 @@ public:
 		float duration	/* 动画持续时长 */
 	);
 
-protected:
 	// 更新动画
-	virtual void _updateCustom() override;
+	virtual void update() override;
 
-	virtual void _init(
+	virtual bool init(
 		Scene * prev,
 		Scene * next
 	) override;
 
-	virtual void _reset() override;
+	virtual void reset() override;
 };
 
 
@@ -135,16 +123,15 @@ public:
 		Direction direction = Direction::Left	/* 场景移动方向 */
 	);
 
-protected:
 	// 更新动画
-	virtual void _updateCustom() override;
+	virtual void update() override;
 
-	virtual void _init(
+	virtual bool init(
 		Scene * prev,
 		Scene * next
 	) override;
 
-	virtual void _reset() override;
+	virtual void reset() override;
 
 protected:
 	Direction _direction;