diff --git a/src/ags.c b/src/ags.c
index a9fcf97..7dd7ec0 100644
--- a/src/ags.c
+++ b/src/ags.c
@@ -202,20 +202,33 @@ void ags_setWindowTitle(const char *title_utf8) {
 	gfx_setWindowTitle(buf);
 }
 
-void ags_getDIBInfo(DispInfo *info) {
-	info->width  = nact->ags.world_width;
-	info->height = nact->ags.world_height;
-	info->depth  = nact->ags.world_depth;
-}
-
-void ags_getViewAreaInfo(DispInfo *info) {
-	gfx_getDisplayInfo(NULL, NULL, &info->depth);
-	info->width  = nact->ags.view_area.w;
-	info->height = nact->ags.view_area.h;
-}
-
-void ags_getWindowInfo(DispInfo *info) {
-	gfx_getDisplayInfo(&info->width, &info->height, &info->depth);
+void ags_getDisplayInfo(enum ags_display display, int *width, int *height, int *depth) {
+	SDL_DisplayMode dm;
+	switch (display) {
+	case AGS_DISPLAY_CURRENT:
+		SDL_GetCurrentDisplayMode(0, &dm);
+		*width = dm.w;
+		*height = dm.h;
+		*depth = SDL_BITSPERPIXEL(dm.format);
+		break;
+	case AGS_DISPLAY_DIB:
+		*width = nact->ags.world_width;
+		*height = nact->ags.world_height;
+		*depth = nact->ags.world_depth;
+		break;
+	case AGS_DISPLAY_VIEW_AREA:
+		SDL_GetCurrentDisplayMode(0, &dm);
+		*width = nact->ags.view_area.w;
+		*height = nact->ags.view_area.h;
+		*depth = SDL_BITSPERPIXEL(dm.format);
+		break;
+	case AGS_DISPLAY_DESKTOP:
+		SDL_GetDesktopDisplayMode(0, &dm);
+		*width = dm.w;
+		*height = dm.h;
+		*depth = SDL_BITSPERPIXEL(dm.format);
+		break;
+	}
 }
 
 void ags_setExposeSwitch(bool expose) {
diff --git a/src/ags.h b/src/ags.h
index 154d624..fc53a44 100644
--- a/src/ags.h
+++ b/src/ags.h
@@ -102,11 +102,12 @@ typedef struct {
 	uint32_t index;
 } PixelColor;
 
-typedef struct {
-	int width;
-	int height;
-	int depth;
-} DispInfo;
+enum ags_display {
+	AGS_DISPLAY_CURRENT,
+	AGS_DISPLAY_DIB,
+	AGS_DISPLAY_VIEW_AREA,
+	AGS_DISPLAY_DESKTOP,
+};
 
 struct _ags {
 	SDL_Color pal[256];         /* system palette */
@@ -145,9 +146,7 @@ void ags_reset(void);
 extern void ags_setWorldSize(int width, int height, int depth);
 extern void ags_setViewArea(int x, int y, int width, int height);
 extern void ags_setWindowTitle(const char *title_utf8);
-extern void ags_getDIBInfo(DispInfo *info);
-extern void ags_getWindowInfo(DispInfo *info);
-extern void ags_getViewAreaInfo(DispInfo *info);
+extern void ags_getDisplayInfo(enum ags_display display, int *width, int *height, int *depth);
 extern bool ags_check_param(int *x, int *y, int *w, int *h);
 extern bool ags_check_param_xy(int *x, int *y);
 extern surface_t *ags_getDIB();
diff --git a/src/cmdz.c b/src/cmdz.c
index 5c75f33..51be2a3 100644
--- a/src/cmdz.c
+++ b/src/cmdz.c
@@ -53,6 +53,14 @@ static uint32_t get_counter(int num) {
 	return sys_get_ticks() - counters[num].base;
 }
 
+static void write_display_info(vmvar_t *var, enum ags_display display) {
+	int width, height, depth;
+	ags_getDisplayInfo(display, &width, &height, &depth);
+	var[0] = width;
+	var[1] = height;
+	var[2] = depth;
+}
+
 void commandZC() {
 	/* システムの使用環境を変更する */
 	int m = getCaliValue();
@@ -394,39 +402,21 @@ void commandZZ2() {
 void commandZZ3() {
 	/* WINDOWSの全画面サイズや表示色数を変数列に返す */
 	vmvar_t *var = getCaliVariable();
-	DispInfo info;
-	
-	ags_getWindowInfo(&info);
-	*var = info.width;
-	*(var + 1) = info.height;
-	*(var + 2) = info.depth;
-	
+	write_display_info(var, AGS_DISPLAY_CURRENT);
 	TRACE("ZZ3 %p:",var);
 }
 
 void commandZZ4() {
 	/* ＤＩＢ の全画面 サイズや色数を変数列に返す */
 	vmvar_t *var = getCaliVariable();
-	DispInfo info;
-	
-	ags_getDIBInfo(&info);
-	*var = info.width;
-	*(var + 1) = info.height;
-	*(var + 2) = info.depth;
-	
+	write_display_info(var, AGS_DISPLAY_DIB);
 	TRACE("ZZ4 %p:",var);
 }
 
 void commandZZ5() {
 	/* ＳＹＳＴＥＭ３．５用表示画面 の サイズや色数を変数列に返す */
 	vmvar_t *var = getCaliVariable();
-	DispInfo info;
-
-	ags_getViewAreaInfo(&info);
-	*var = info.width;
-	*(var + 1) = info.height;
-	*(var + 2) = info.depth;
-	
+	write_display_info(var, AGS_DISPLAY_VIEW_AREA);
 	TRACE("ZZ5 %p:",var);
 }
 
@@ -449,13 +439,7 @@ void commandZZ8() {
 void commandZZ9() {
 	/* 起動時のスクリーンサイズを取得する */
 	vmvar_t *var = getCaliVariable();
-	DispInfo info;
-	
-	ags_getWindowInfo(&info);
-	*var = info.width;
-	*(var + 1) = info.height;
-	*(var + 2) = info.depth;
-	
+	write_display_info(var, AGS_DISPLAY_DESKTOP);
 	TRACE("ZZ9 %p:",var);
 }
 
diff --git a/src/gfx.h b/src/gfx.h
index d2ac7d3..1acc3f5 100644
--- a/src/gfx.h
+++ b/src/gfx.h
@@ -38,7 +38,6 @@ SDL_Window *gfx_getWindow(void);
 void gfx_warpMouse(int x, int y);
 SDL_Rect gfx_viewToWindowRect(SDL_Rect rect);
 void gfx_setWindowTitle(char *name);
-void gfx_getDisplayInfo(int *width, int *height, int *depth);
 void gfx_setFullscreen(bool on);
 bool gfx_isFullscreen(void);
 void gfx_raiseWindow(void);
diff --git a/src/gfx_video.c b/src/gfx_video.c
index e4ccdab..a5fcc9d 100644
--- a/src/gfx_video.c
+++ b/src/gfx_video.c
@@ -170,14 +170,6 @@ void gfx_setWorldSize(int width, int height, int depth) {
 	SDL_FillRect(main_surface, NULL, 0);
 }
 
-void gfx_getDisplayInfo(int *width, int *height, int *depth) {
-	SDL_DisplayMode dm;
-	SDL_GetCurrentDisplayMode(0, &dm);
-	if (width)  *width  = dm.w;
-	if (height) *height = dm.h;
-	if (depth)  *depth  = SDL_BITSPERPIXEL(dm.format);
-}
-
 void gfx_getViewSize(int *width, int *height) {
 	if (width)
 		*width = view_w;