diff --git a/Easy2D/2d/DebugNode.cpp b/Easy2D/2d/DebugNode.cpp
index 4c542c82..c6c867e2 100644
--- a/Easy2D/2d/DebugNode.cpp
+++ b/Easy2D/2d/DebugNode.cpp
@@ -63,8 +63,8 @@ namespace easy2d
 	{
 		E2D_NOT_USED(dt);
 
-		frame_time_.push_back(time::Now());
-		while (frame_time_.back() - frame_time_.front() >= time::Second)
+		frame_time_.push_back(Time::Now());
+		while (frame_time_.back() - frame_time_.front() >= time::Sec)
 		{
 			frame_time_.erase(frame_time_.begin());
 		}
diff --git a/Easy2D/2d/DebugNode.h b/Easy2D/2d/DebugNode.h
index aaa67c80..a6aaa78a 100644
--- a/Easy2D/2d/DebugNode.h
+++ b/Easy2D/2d/DebugNode.h
@@ -37,6 +37,6 @@ namespace easy2d
 
 	protected:
 		TextPtr				debug_text_;
-		Array<TimePoint>	frame_time_;
+		Array<Time>	frame_time_;
 	};
 }
diff --git a/Easy2D/base/time.cpp b/Easy2D/base/time.cpp
index fd634356..72d83760 100644
--- a/Easy2D/base/time.cpp
+++ b/Easy2D/base/time.cpp
@@ -28,65 +28,82 @@ namespace easy2d
 	namespace time
 	{
 		//-------------------------------------------------------
-		// TimePoint
+		// Time
 		//-------------------------------------------------------
 
-		TimePoint::TimePoint()
+		Time::Time()
 		{
 		}
 
-		TimePoint::TimePoint(long dur)
+		Time::Time(long dur)
 			: dur_(dur)
 		{
 		}
 
-		const TimePoint TimePoint::operator+(const Duration & dur) const
+		const Time Time::operator+(const Duration & dur) const
 		{
-			return TimePoint{ dur_ + dur.Milliseconds() };
+			return Time{ dur_ + dur.Milliseconds() };
 		}
 
-		const TimePoint TimePoint::operator-(const Duration & dur) const
+		const Time Time::operator-(const Duration & dur) const
 		{
-			return TimePoint{ dur_ - dur.Milliseconds() };
+			return Time{ dur_ - dur.Milliseconds() };
 		}
 
-		TimePoint & TimePoint::operator+=(const Duration & other)
+		Time & Time::operator+=(const Duration & other)
 		{
 			dur_ += other.Milliseconds();
 			return (*this);
 		}
 
-		TimePoint & TimePoint::operator-=(const Duration &other)
+		Time & Time::operator-=(const Duration &other)
 		{
 			dur_ -= other.Milliseconds();
 			return (*this);
 		}
 
-		const Duration TimePoint::operator-(const TimePoint & other) const
+		const Duration Time::operator-(const Time & other) const
 		{
 			return Duration(dur_ - other.dur_);
 		}
 
+		Time Time::Now() E2D_NOEXCEPT
+		{
+			static LARGE_INTEGER freq = {};
+			if (freq.QuadPart == 0LL)
+			{
+				// the function will always succceed on systems that run Windows XP or later
+				QueryPerformanceFrequency(&freq);
+			}
+
+			LARGE_INTEGER count;
+			QueryPerformanceCounter(&count);
+
+			const long long whole = (count.QuadPart / freq.QuadPart) * 1000LL;
+			const long long part = (count.QuadPart % freq.QuadPart) * 1000LL / freq.QuadPart;
+			return Time{ static_cast<long>(whole + part) };
+		}
+
 
 		//-------------------------------------------------------
 		// Duration
 		//-------------------------------------------------------
 
-		const Duration Millisecond	= 1L;
-		const Duration Second		= 1000 * Millisecond;
-		const Duration Minute		= 60 * Second;
-		const Duration Hour			= 60 * Minute;
+		const Duration Ms	= 1L;
+		const Duration Sec	= 1000 * Ms;
+		const Duration Min	= 60 * Sec;
+		const Duration Hour	= 60 * Min;
 
 		namespace
 		{
 			const auto duration_regex = std::wregex(LR"([-+]?([0-9]*(\.[0-9]*)?[a-z]+)+)");
 
-			typedef std::unordered_map<std::wstring, Duration> UnitMap;
+			typedef std::unordered_map<String, Duration> UnitMap;
 			const auto unit_map = UnitMap
 			{
-				{L"ms", Millisecond},
-				{L"s", Second},
-				{L"m", Minute},
+				{L"ms", Ms},
+				{L"s", Sec},
+				{L"m", Min},
 				{L"h", Hour}
 			};
 		}
@@ -103,49 +120,53 @@ namespace easy2d
 
 		float Duration::Seconds() const
 		{
-			long long sec = milliseconds_ / Second.milliseconds_;
-			long long ms = milliseconds_ % Second.milliseconds_;
+			long sec = milliseconds_ / Sec.milliseconds_;
+			long ms = milliseconds_ % Sec.milliseconds_;
 			return static_cast<float>(sec) + static_cast<float>(ms) / 1000.f;
 		}
 
 		float Duration::Minutes() const
 		{
-			long long min = milliseconds_ / Minute.milliseconds_;
-			long long ms = milliseconds_ % Minute.milliseconds_;
+			long min = milliseconds_ / Min.milliseconds_;
+			long ms = milliseconds_ % Min.milliseconds_;
 			return static_cast<float>(min) + static_cast<float>(ms) / (60 * 1000.f);
 		}
 
 		float Duration::Hours() const
 		{
-			long long hour = milliseconds_ / Hour.milliseconds_;
-			long long ms = milliseconds_ % Hour.milliseconds_;
+			long hour = milliseconds_ / Hour.milliseconds_;
+			long ms = milliseconds_ % Hour.milliseconds_;
 			return static_cast<float>(hour) + static_cast<float>(ms) / (60 * 60 * 1000.f);
 		}
 
-		std::wstring easy2d::time::Duration::ToString() const
+		String easy2d::time::Duration::ToString() const
 		{
 			if (IsZero())
 			{
-				return std::wstring(L"0s");
+				return String(L"0s");
 			}
 
-			std::wstring result;
-			long long hour = milliseconds_ / Hour.milliseconds_;
-			long long min = milliseconds_ / Minute.milliseconds_ - hour * 60;
-			long long sec = milliseconds_ / Second.milliseconds_ - (hour * 60 * 60 + min * 60);
-			long long ms = milliseconds_ % Second.milliseconds_;
-
-			if (milliseconds_ < 0)
+			String result;
+			long total_ms = milliseconds_;
+			if (total_ms < 0)
+			{
 				result.append(L"-");
+				total_ms = -total_ms;
+			}
+
+			long hour = total_ms / Hour.milliseconds_;
+			long min = total_ms / Min.milliseconds_ - hour * 60;
+			long sec = total_ms / Sec.milliseconds_ - (hour * 60 * 60 + min * 60);
+			long ms = total_ms % Sec.milliseconds_;
 
 			if (hour)
 			{
-				result.append(std::to_wstring(hour)).append(L"h");
-				result.append(std::to_wstring(min)).append(L"m");
+				result.append(easy2d::to_wstring(hour)).append(L"h");
+				result.append(easy2d::to_wstring(min)).append(L"m");
 			}
 			else if(min)
 			{
-				result.append(std::to_wstring(min)).append(L"m");
+				result.append(easy2d::to_wstring(min)).append(L"m");
 			}
 
 			if (ms != 0)
@@ -162,7 +183,7 @@ namespace easy2d
 			}
 			else if (sec != 0)
 			{
-				result.append(std::to_wstring(sec)).append(L"s");
+				result.append(easy2d::to_wstring(sec)).append(L"s");
 			}
 			return result;
 		}
@@ -340,51 +361,16 @@ namespace easy2d
 			return dur * val;
 		}
 
-		std::wostream & easy2d::time::operator<<(std::wostream & out, const Duration & dur)
-		{
-			return out << dur.ToString();
-		}
-
-		std::wistream & easy2d::time::operator>>(std::wistream & in, Duration & dur)
-		{
-			std::wstring str;
-			in >> str;
-			dur = time::ParseDuration(str);
-			return in;
-		}
-
-
-		//-------------------------------------------------------
-		// Functions
-		//-------------------------------------------------------
-
-		TimePoint easy2d::time::Now() E2D_NOEXCEPT
-		{
-			static LARGE_INTEGER freq = {};
-			if (freq.QuadPart == 0LL)
-			{
-				// the function will always succceed on systems that run Windows XP or later
-				QueryPerformanceFrequency(&freq);
-			}
-
-			LARGE_INTEGER count;
-			QueryPerformanceCounter(&count);
-
-			const long long whole = (count.QuadPart / freq.QuadPart) * 1000LL;
-			const long long part = (count.QuadPart % freq.QuadPart) * 1000LL / freq.QuadPart;
-			return TimePoint{ static_cast<long>(whole + part) };
-		}
-
-		Duration easy2d::time::ParseDuration(const std::wstring & str)
+		Duration Duration::Parse(const String& str)
 		{
 			size_t len = str.length();
 			size_t pos = 0;
 			bool negative = false;
 			Duration d;
 
-			if (!std::regex_match(str, duration_regex))
+			if (!std::regex_match(str.c_str(), duration_regex))
 			{
-				E2D_ERROR_LOG(L"time::ParseDuration failed, invalid duration");
+				E2D_ERROR_LOG(L"Duration::Parse failed, invalid duration");
 				return Duration();
 			}
 
@@ -410,12 +396,12 @@ namespace easy2d
 					}
 				}
 
-				std::wstring num_str = str.substr(pos, i - pos);
+				String num_str = str.substr(pos, i - pos);
 				pos = i;
 
 				if (num_str.empty() || num_str == L".")
 				{
-					E2D_ERROR_LOG(L"time::ParseDuration failed, invalid duration");
+					E2D_ERROR_LOG(L"Duration::Parse failed, invalid duration");
 					return Duration();
 				}
 
@@ -429,16 +415,16 @@ namespace easy2d
 					}
 				}
 
-				std::wstring unit_str = str.substr(pos, i - pos);
+				String unit_str = str.substr(pos, i - pos);
 				pos = i;
 
 				if (unit_map.find(unit_str) == unit_map.end())
 				{
-					E2D_ERROR_LOG(L"time::ParseDuration failed, invalid duration");
+					E2D_ERROR_LOG(L"Duration::Parse failed, invalid duration");
 					return Duration();
 				}
 
-				double num = std::stod(num_str);
+				double num = std::wcstod(num_str.c_str(), nullptr);
 				Duration unit = unit_map.at(unit_str);
 				d += unit * num;
 			}
diff --git a/Easy2D/base/time.h b/Easy2D/base/time.h
index adb135d6..ccca1ad3 100644
--- a/Easy2D/base/time.h
+++ b/Easy2D/base/time.h
@@ -20,6 +20,9 @@
 
 #pragma once
 #include "../macros.h"
+#include "../common/String.h"
+#include <ostream>
+#include <istream>
 
 namespace easy2d
 {
@@ -28,9 +31,9 @@ namespace easy2d
 		// 时间段
 		//
 		// 时间段表示法:
-		//     5 秒: time::Second * 5
+		//     5 秒: time::Sec * 5
 		//     1.5 小时: time::Hour * 1.5
-		//     3 小时 45 分 15 秒: time::Hour * 3 + time::Minute * 45 + time::Second * 15
+		//     3 小时 45 分 15 秒: time::Hour * 3 + time::Min * 45 + time::Sec * 15
 		// 在 VS2015 及更高版本可以使用 time literals:
 		//     5 秒: 5_s
 		//     1.5 小时: 1.5_h
@@ -60,7 +63,7 @@ namespace easy2d
 			inline bool IsZero() const { return milliseconds_ == 0LL; }
 
 			// 转为字符串
-			std::wstring ToString() const;
+			String ToString() const;
 
 			inline operator bool() const { return !IsZero(); }
 
@@ -102,60 +105,75 @@ namespace easy2d
 			friend const Duration operator/ (float, const Duration &);
 			friend const Duration operator/ (double, const Duration &);
 
-			friend std::wostream& operator<< (std::wostream &, const Duration &);
-			friend std::wistream& operator>> (std::wistream &, Duration &);
+		public:
+			// 时间段格式化
+			//
+			// 时间段字符串允许是有符号的浮点数, 并且带有时间单位后缀
+			// 例如: "300ms", "-1.5h", "2h45m"
+			// 允许的时间单位有 "ms", "s", "m", "h"
+			static Duration Parse(const String& parse_str);
+
+			template <typename _Char>
+			friend inline std::basic_ostream<_Char>& operator<<(std::basic_ostream<_Char>& out, const Duration& dur)
+			{
+				return out << dur.ToString();
+			}
+
+			template <typename _Char>
+			friend inline std::basic_istream<_Char>& operator>>(std::basic_istream<_Char>& in, Duration& dur)
+			{
+				String str;
+				if (in >> str)
+				{
+					dur = Duration::Parse(str);
+				}
+				return in;
+			}
 
 		private:
 			long milliseconds_;
 		};
 
 		/* 预定义的时间段 */
-		E2D_API extern const Duration Millisecond;	// 毫秒
-		E2D_API extern const Duration Second;		// 秒
-		E2D_API extern const Duration Minute;		// 分钟
-		E2D_API extern const Duration Hour;			// 小时
+		E2D_API extern const Duration Ms;		// 毫秒
+		E2D_API extern const Duration Sec;		// 秒
+		E2D_API extern const Duration Min;		// 分钟
+		E2D_API extern const Duration Hour;		// 小时
 
 
 		// 时间
 		//
-		// 获取当前时间: TimePoint now = time::Now();
+		// 获取当前时间: Time now = Time::Now();
 		// 两时间相减, 得到一个 Duration 对象, 例如:
-		//     TimePoint t1, t2;
+		//     Time t1, t2;
 		//     int ms = (t2 - t1).Milliseconds();  // 获取两时间相差的毫秒数
 		// 
-		struct E2D_API TimePoint
+		struct E2D_API Time
 		{
-			TimePoint();
+			Time();
 
-			TimePoint(long);
+			Time(long);
 
 			// 是否是零时
 			inline bool IsZero() const { return dur_ == 0; }
 
-			const TimePoint operator + (const Duration &) const;
-			const TimePoint operator - (const Duration &) const;
+			const Time operator + (const Duration &) const;
+			const Time operator - (const Duration &) const;
 
-			TimePoint& operator += (const Duration &);
-			TimePoint& operator -= (const Duration &);
+			Time& operator += (const Duration &);
+			Time& operator -= (const Duration &);
 
-			const Duration operator - (const TimePoint &) const;
+			const Duration operator - (const Time &) const;
+
+		public:
+			// 获取当前时间
+			// 由于该时间点基于系统启动时间开始计算, 所以无法格式化该时间, 
+			// 也无法获得该时间的 Unix 时间戳
+			static Time Now() E2D_NOEXCEPT;
 
 		private:
 			long dur_;
 		};
-
-		// 获取当前时间
-		// 
-		// 由于该时间点基于系统启动时间开始计算, 所以无法格式化该时间, 
-		// 也无法获得该时间的 Unix 时间戳
-		E2D_API TimePoint Now() E2D_NOEXCEPT;
-
-		// 时间段格式化
-		//
-		// 时间段字符串允许是有符号的浮点数, 并且带有时间单位后缀
-		// 例如: "300ms", "-1.5h", "2h45m"
-		// 允许的时间单位有 "ms", "s", "m", "h"
-		E2D_API Duration ParseDuration(const std::wstring& parse_str);
 	}
 }
 
@@ -172,17 +190,17 @@ namespace easy2d
 	{
 		inline const easy2d::time::Duration operator "" _ms(long double val)
 		{
-			return easy2d::time::Millisecond * val;
+			return easy2d::time::Ms * val;
 		}
 
 		inline const easy2d::time::Duration operator "" _s(long double val)
 		{
-			return easy2d::time::Second * val;
+			return easy2d::time::Sec * val;
 		}
 
 		inline const easy2d::time::Duration operator "" _m(long double val)
 		{
-			return easy2d::time::Minute * val;
+			return easy2d::time::Min * val;
 		}
 
 		inline const easy2d::time::Duration operator "" _h(long double val)
@@ -192,17 +210,17 @@ namespace easy2d
 
 		inline const easy2d::time::Duration operator "" _ms(unsigned long long val)
 		{
-			return easy2d::time::Millisecond * val;
+			return easy2d::time::Ms * val;
 		}
 
 		inline const easy2d::time::Duration operator "" _s(unsigned long long val)
 		{
-			return easy2d::time::Second * val;
+			return easy2d::time::Sec * val;
 		}
 
 		inline const easy2d::time::Duration operator "" _m(unsigned long long val)
 		{
-			return easy2d::time::Minute * val;
+			return easy2d::time::Min * val;
 		}
 
 		inline const easy2d::time::Duration operator "" _h(unsigned long long val)
diff --git a/Easy2D/common/String.h b/Easy2D/common/String.h
index 61806d9d..50b33050 100644
--- a/Easy2D/common/String.h
+++ b/Easy2D/common/String.h
@@ -351,6 +351,9 @@ namespace easy2d
 	std::basic_ostream<String::value_type>& operator<<(std::basic_ostream<String::value_type>& os, const String & str);
 	std::basic_istream<String::value_type>& operator>>(std::basic_istream<String::value_type>& is, String & str);
 
+	std::basic_ostream<char>& operator<<(std::basic_ostream<char>& os, const String& str);
+	std::basic_istream<char>& operator>>(std::basic_istream<char>& is, String& str);
+
 	//
 	// to_string functions
 	//
@@ -1236,6 +1239,21 @@ namespace easy2d
 		return is;
 	}
 
+	inline std::basic_ostream<char>& operator<<(std::basic_ostream<char>& os, const String& str)
+	{
+		return os << str.to_string();
+	}
+
+	inline std::basic_istream<char>& operator>>(std::basic_istream<char>& is, String& str)
+	{
+		std::string tmp;
+		if (is >> tmp)
+		{
+			str = tmp;
+		}
+		return is;
+	}
+
 	//
 	// details of to_string functions
 	//
diff --git a/Easy2D/platform/Application.cpp b/Easy2D/platform/Application.cpp
index 9280e77c..e8197d43 100644
--- a/Easy2D/platform/Application.cpp
+++ b/Easy2D/platform/Application.cpp
@@ -328,9 +328,9 @@ namespace easy2d
 
 	void Application::Update()
 	{
-		static auto last = time::Now();
+		static auto last = Time::Now();
 
-		const auto now = time::Now();
+		const auto now = Time::Now();
 		const auto dt = (now - last) * time_scale_;
 		last = now;
 
diff --git a/Easy2D/renderer/render.cpp b/Easy2D/renderer/render.cpp
index 068dab1e..53c69c67 100644
--- a/Easy2D/renderer/render.cpp
+++ b/Easy2D/renderer/render.cpp
@@ -141,7 +141,7 @@ namespace easy2d
 
 		if (collecting_data_)
 		{
-			status_.start = time::Now();
+			status_.start = Time::Now();
 			status_.primitives = 0;
 		}
 
@@ -186,7 +186,7 @@ namespace easy2d
 
 		if (collecting_data_)
 		{
-			status_.duration = time::Now() - status_.start;
+			status_.duration = Time::Now() - status_.start;
 		}
 		return hr;
 	}
diff --git a/Easy2D/renderer/render.h b/Easy2D/renderer/render.h
index db8dd6b0..e6752d2d 100644
--- a/Easy2D/renderer/render.h
+++ b/Easy2D/renderer/render.h
@@ -33,7 +33,7 @@ namespace easy2d
 {
 	struct RenderStatus
 	{
-		TimePoint start;
+		Time start;
 		Duration duration;
 		int primitives;
 	};
diff --git a/samples/HelloWorld/main.cpp b/samples/HelloWorld/main.cpp
index 8946ccd8..5bfd8ad8 100644
--- a/samples/HelloWorld/main.cpp
+++ b/samples/HelloWorld/main.cpp
@@ -2,17 +2,19 @@
 
 #include "easy2d.h"
 
+using namespace easy2d;
+
 const int WINDOW_WIDTH = 640;
 const int WINDOW_HEIGHT = 480;
 
 class MainScene
-	: public easy2d::Scene
+	: public Scene
 {
 public:
 	MainScene()
 	{
 		// 创建文字节点
-		easy2d::TextPtr text = new easy2d::Text(L"Hello Easy2D!");
+		TextPtr text = new Text(L"Hello Easy2D!");
 		// 设置节点大小为文字布局大小
 		text->SetSize(text->GetLayoutSize());
 		// 修改节点位置, 使节点在屏幕上居中
@@ -29,10 +31,10 @@ int WINAPI wWinMain(HINSTANCE, HINSTANCE, PWSTR, int)
 	try
 	{
 		// 创建 Easy2D 程序实例
-		easy2d::Application app;
+		Application app;
 
 		// 创建初始化选项
-		easy2d::Options options;
+		Options options;
 		// 设置窗口宽高
 		options.width = WINDOW_WIDTH;
 		options.height = WINDOW_HEIGHT;
@@ -40,7 +42,7 @@ int WINAPI wWinMain(HINSTANCE, HINSTANCE, PWSTR, int)
 		app.Init(options);
 
 		// 创建场景并进入
-		easy2d::ScenePtr scene = new MainScene;
+		ScenePtr scene = new MainScene;
 		app.EnterScene(scene);
 
 		// 运行