--- a/window/system.cc
+++ b/window/system.cc
@@ -25,84 +25,88 @@
  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-#include<SDL.h>
-#include"system.h"
-#include<iostream>
-#include<stdio.h>
+#include <SDL.h>
+#include "system.h"
+#include <iostream>
+#include <stdio.h>
 
 using namespace std;
 
 // void SDL_SetEventFilter(SDL_EventFilter filter);
 // typedef int (*SDL_EventFilter)(const SDL_Event *event);
 namespace System {
+	Main* Main::instance = NULL;
 
-Main* Main::instance = 0;
+	int Main::event_filter(const SDL_Event* event) {
+		return 1; /* throw all event */
+	}
 
-int Main::event_filter(const SDL_Event* event) {
-	return 1; /* throw all event */
-}
+	Main::Main(void) {
+		instance = this;
+		framerate = 20;
+		cursor = NULL;
+	}
 
-Main::Main(void) {
-	instance = this;
-	framerate = 20;
-	cursor = 0;
-}
-Main::~Main() {
-	if (cursor) delete cursor;
-}
-void Main::Quit(void) {
-	is_exit = true;
-}
-void Main::EnableVideo(void) {
-	is_video_update = true;
-}
-void Main::DisableVideo(void) {
-	is_video_update = false;
-}
-bool Main::is_exit = false;
-bool Main::is_video_update = true;
+	Main::~Main() {
+		if (cursor) delete cursor;
+	}
+
+	void Main::Quit(void) {
+		is_exit = true;
+	}
+
+	void Main::EnableVideo(void) {
+		is_video_update = true;
+	}
+
+	void Main::DisableVideo(void) {
+		is_video_update = false;
+	}
+
+	bool Main::is_exit = false;
+	bool Main::is_video_update = true;
 
-void Main::Mainloop(void) {
-	SDL_SetEventFilter(&event_filter);
-	Uint32 old_time = 0;
-	while(!is_exit) {
-		Uint32 start_time = SDL_GetTicks();
-		if (! event.Exec(start_time)) break;
-		if (start_time - old_time > 1000/framerate) {
-			if (is_video_update) root.ExecUpdate();
-			event.Exec(Event::Time::FRAME_UPDATE);
-			cout.flush();
-			old_time = start_time;
-		}
+	void Main::Mainloop(void) {
+		SDL_SetEventFilter(&event_filter);
+		Uint32 old_time = 0;
+		while(!is_exit) {
+			Uint32 start_time = SDL_GetTicks();
+			if (! event.Exec(start_time)) break;
+			if (start_time - old_time > 1000/framerate) {
+				if (is_video_update) root.ExecUpdate();
+				event.Exec(Event::Time::FRAME_UPDATE);
+				cout.flush();
+				old_time = start_time;
+			}
 
-// 問題：
-// z 軸と xy 軸の相互干渉；高速化
-// 移動するウィジット描画の高速化
-// キャッシュ
-// 文字列の一部のみ更新の高速化
-// 「階層 z で x なる領域無効化、y なる領域生成」で良い？＞Expose
-/*
-		Uint32 end_time = SDL_GetTicks();
-		Uint32 delay = (end_time-start_time);
-		if(delay < 1000/framerate) SDL_Delay(1000/framerate - delay);
-		else SDL_Delay(0);
-*/
-		SDL_Delay(0);
-	};
-}
+	// 問題：
+	// z 軸と xy 軸の相互干渉；高速化
+	// 移動するウィジット描画の高速化
+	// キャッシュ
+	// 文字列の一部のみ更新の高速化
+	// 「階層 z で x なる領域無効化、y なる領域生成」で良い？＞Expose
+	/*
+			Uint32 end_time = SDL_GetTicks();
+			Uint32 delay = (end_time-start_time);
+			if(delay < 1000/framerate) SDL_Delay(1000/framerate - delay);
+			else SDL_Delay(0);
+	*/
+			SDL_Delay(0);
+		}
+	}
 
-void Main::SetCursor(Surface* s, const Rect& r) {
-	if (instance == 0) return;
-	if (instance->cursor) delete instance->cursor;
-	if (s == 0) { // カーソル消去
-		instance->cursor = 0;
-	} else if (s == DEFAULT_MOUSECURSOR) {
-		instance->cursor = 0;
-		SDL_ShowCursor(SDL_ENABLE);
-	} else {
-		instance->cursor = new WidMouseCursor(instance->event, instance->root.root, s, r.lx, r.ty, r.width(), r.height());
-		instance->cursor->show();
-		SDL_ShowCursor(SDL_DISABLE);
+	void Main::SetCursor(Surface* s, const Rect& r) {
+		if (instance == 0) return;
+		if (instance->cursor) delete instance->cursor;
+		if (s == 0) { // カーソル消去
+			instance->cursor = 0;
+		} else if (s == DEFAULT_MOUSECURSOR) {
+			instance->cursor = 0;
+			SDL_ShowCursor(SDL_ENABLE);
+		} else {
+			instance->cursor = new WidMouseCursor(instance->event, instance->root.root, s, r.lx, r.ty, r.width(), r.height());
+			instance->cursor->show();
+			SDL_ShowCursor(SDL_DISABLE);
+		}
 	}
 }
-}