diff --git a/cg.c b/cg.c
index f1f4935..4a7b8a5 100644
--- a/cg.c
+++ b/cg.c
@@ -48,7 +48,7 @@ void _cg_free(struct cg *cg)
 	if (!cg)
 		return;
 	if (cg->s) {
-		if (cg->no >= 0)
+		if (cg->pixel_alloc)
 			free(cg->s->pixels);
 		SDL_FreeSurface(cg->s);
 	}
@@ -86,8 +86,9 @@ bool cg_load(struct cg *cg, int no)
 	//  size is only pixel data size
 	switch(type) {
 	case ALCG_QNT:
-		qnt_extract(cg, dfile->data);
-		size = (cg->rect.w * cg->rect.h) * 3;
+		cg->type = ALCG_QNT;
+		cg->s = qnt_extract(dfile->data);
+		cg->pixel_alloc = true;
 		break;
 	case ALCG_AJP:
 		// TODO
@@ -102,28 +103,24 @@ bool cg_load(struct cg *cg, int no)
 	// ok to free
 	ald_free_data(dfile);
 
-	cg->no = no;
 	return true;
 }
 
-void _cg_init(struct cg *cg, int width, int height, uint8_t r, uint8_t g, uint8_t b, uint8_t a)
+void _cg_init(struct cg *cg)
 {
-	cg->no = -1;
-	cg->rect.w = width;
-	cg->rect.h = height;
-	cg->color = (SDL_Color) { .r = r, .g = g, .b = b, .a = a };
+	cg->pixel_alloc = false;
 	cg->s = NULL;
 }
 
-void cg_reinit(struct cg *cg, int width, int height, uint8_t r, uint8_t g, uint8_t b, uint8_t a)
+void cg_reinit(struct cg *cg)
 {
 	_cg_free(cg);
-	_cg_init(cg, width, height, r, g, b, a);
+	_cg_init(cg);
 }
 
-struct cg *cg_init(int width, int height, uint8_t r, uint8_t g, uint8_t b, uint8_t a)
+struct cg *cg_init(void)
 {
 	struct cg *cg = calloc(1, sizeof(struct cg));
-	_cg_init(cg, width, height, r, g, b, a);
+	_cg_init(cg);
 	return cg;
 }
diff --git a/cg.h b/cg.h
index 89b0f30..0bb8119 100644
--- a/cg.h
+++ b/cg.h
@@ -29,10 +29,9 @@
  */
 enum cg_type {
 	ALCG_UNKNOWN = 1,
-	ALCG_BMP24   = 2,
-	ALCG_QNT     = 3,
-	ALCG_AJP     = 4,
-	ALCG_PNG     = 5
+	ALCG_QNT     = 2,
+	ALCG_AJP     = 3,
+	ALCG_PNG     = 4
 };
 
 /*
@@ -40,18 +39,14 @@ enum cg_type {
  */
 struct cg {
 	enum cg_type type; // cg format type
-	int no;
-	int z;
-	bool show;
-	SDL_Color color;
-	Rectangle rect;
+	bool pixel_alloc;
 	SDL_Surface *s;
 };
 
 bool cg_exists(int no);
 bool cg_load(struct cg *cg, int no);
-struct cg *cg_init(int width, int height, uint8_t r, uint8_t g, uint8_t b, uint8_t a);
-void cg_reinit(struct cg *cg, int width, int height, uint8_t r, uint8_t g, uint8_t b, uint8_t a);
+struct cg *cg_init(void);
+void cg_reinit(struct cg *cg);
 void cg_free(struct cg *cg);
 
 #endif /* SYSTEM4_CG_H */
diff --git a/hll/SACT2.c b/hll/SACT2.c
index fe37fec..404d502 100644
--- a/hll/SACT2.c
+++ b/hll/SACT2.c
@@ -23,325 +23,234 @@
 #include "../input.h"
 #include "../queue.h"
 #include "../sdl_core.h"
-
-struct SACT2_sprite {
-	TAILQ_ENTRY(SACT2_sprite) entry;
-	struct cg *cg;
-	bool used;
-};
-
-static struct SACT2_sprite *sprites = NULL;
-static int nr_sprites = 0;
-
-TAILQ_HEAD(listhead, SACT2_sprite) sprite_list =
-	TAILQ_HEAD_INITIALIZER(sprite_list);
-
-static void sprite_register(struct SACT2_sprite *sp)
-{
-	struct SACT2_sprite *p;
-	TAILQ_FOREACH(p, &sprite_list, entry) {
-		if (p->cg->z > sp->cg->z) {
-			TAILQ_INSERT_BEFORE(p, sp, entry);
-			return;
-		}
-	}
-	TAILQ_INSERT_TAIL(&sprite_list, sp, entry);
-}
+#include "../sact.h"
 
 // int Init(imain_system pIMainSystem, int nCGCacheSize)
-hll_defun(Init, args)
-{
-	sdl_initialize();
-	hll_return(1);
-}
-
+hll_defun_inline(Init, sact_Init());
 // int Error(string strErr)
-hll_unimplemented(SACT2, Error)
+hll_unimplemented(SACT2, Error);
 // int SetWP(int nCG)
-hll_warn_unimplemented(SACT2, SetWP, 1)
+hll_warn_unimplemented(SACT2, SetWP, 1);
 // int SetWP_Color(int nR, int nG, int nB)
-hll_warn_unimplemented(SACT2, SetWP_Color, 1)
+hll_warn_unimplemented(SACT2, SetWP_Color, 1);
 // int WP_GetSP(int nSP)
-hll_unimplemented(SACT2, WP_GetSP)
+hll_unimplemented(SACT2, WP_GetSP);
 // int WP_SetSP(int nSP)
-hll_unimplemented(SACT2, WP_SetSP)
-
+hll_unimplemented(SACT2, WP_SetSP);
 // int GetScreenWidth(void)
-hll_defun(GetScreenWidth, _)
-{
-	hll_return(config.view_width);
-}
-
+hll_defun_inline(GetScreenWidth, config.view_width);
 // int GetScreenHeight(void)
-hll_defun(GetScreenHeight, _)
-{
-	hll_return(config.view_height);
-}
-
+hll_defun_inline(GetScreenHeight, config.view_height);
 // int GetMainSurfaceNumber(void)
-hll_unimplemented(SACT2, GetMainSurfaceNumber)
-
+hll_unimplemented(SACT2, GetMainSurfaceNumber);
 // int Update(void)
-hll_defun(Update, _)
-{
-	handle_events();
-	struct SACT2_sprite *p;
-	TAILQ_FOREACH_REVERSE(p, &sprite_list, listhead, entry) {
-		if (!p->cg->show)
-			continue;
-		sdl_draw_cg(p->cg);
-	}
-	sdl_update_screen();
-	hll_return(1);
-}
-
+hll_defun_inline(Update, sact_Update());
 // int Effect(int nType, int nTime, int nfKey)
-hll_warn_unimplemented(SACT2, Effect, 1)
+hll_warn_unimplemented(SACT2, Effect, 1);
 // int EffectSetMask(int nCG)
-hll_unimplemented(SACT2, EffectSetMask)
+hll_unimplemented(SACT2, EffectSetMask);
 // int EffectSetMaskSP(int nSP)
-hll_unimplemented(SACT2, EffectSetMaskSP)
+hll_unimplemented(SACT2, EffectSetMaskSP);
 // void QuakeScreen(int nAmplitudeX, int nAmplitudeY, int nTime, int nfKey)
-hll_unimplemented(SACT2, QuakeScreen)
+hll_unimplemented(SACT2, QuakeScreen);
 // void QUAKE_SET_CROSS(int nAmpX, int nAmpY)
-hll_unimplemented(SACT2, QUAKE_SET_CROSS)
+hll_unimplemented(SACT2, QUAKE_SET_CROSS);
 // void QUAKE_SET_ROTATION(int nAmp, int nCycle)
-hll_unimplemented(SACT2, QUAKE_SET_ROTATION)
-
+hll_unimplemented(SACT2, QUAKE_SET_ROTATION);
 // int SP_GetUnuseNum(int nMin)
-hll_defun(SP_GetUnuseNum, args)
-{
-	int nMin = args[0].i;
-
-	for (int i = nMin; i < nr_sprites; i++) {
-		if (!sprites[i].used)
-			hll_return(i);
-	}
-
-	int n = max(nMin, nr_sprites);
-	nr_sprites = n + 256;
-	sprites = xrealloc(sprites, sizeof(struct SACT2_sprite) * nr_sprites);
-	hll_return(n);
-}
-
+hll_defun_inline(SP_GetUnuseNum, sact_SP_GetUnuseNum(a[0].i));
 // int SP_Count(void)
-hll_unimplemented(SACT2, SP_Count)
+hll_unimplemented(SACT2, SP_Count);
 // int SP_Enum(ref array@int anSP)
-hll_unimplemented(SACT2, SP_Enum)
-
+hll_unimplemented(SACT2, SP_Enum);
 // int SP_GetMaxZ(void)
-hll_defun(SP_GetMaxZ, args)
-{
-	if (TAILQ_EMPTY(&sprite_list))
-		hll_return(0);
-	hll_return(TAILQ_LAST(&sprite_list, listhead)->cg->z);
-}
-
+hll_defun_inline(SP_GetMaxZ, sact_SP_GetMaxZ());
 // int SP_SetCG(int nSP, int nCG)
-hll_defun(SP_SetCG, args)
-{
-	int sp = args[0].i;
-	int cg = args[1].i;
-
-	if (!cg_load(sprites[sp].cg, cg - 1))
-		hll_return(0);
-	hll_return(1);
-}
-
+hll_defun_inline(SP_SetCG, sact_SP_SetCG(a[0].i, a[1].i));
 // int SP_SetCGFromFile(int nSP, string pIStringFileName)
-hll_unimplemented(SACT2, SP_SetCGFromFile)
+hll_unimplemented(SACT2, SP_SetCGFromFile);
 // int SP_SaveCG(int nSP, string pIStringFileName)
-hll_unimplemented(SACT2, SP_SaveCG)
-
+hll_unimplemented(SACT2, SP_SaveCG);
 // int SP_Create(int nSP, int nWidth, int nHeight, int nR, int nG, int nB, int nBlendRate)
-hll_defun(SP_Create, args)
-{
-	int sp     = args[0].i;
-	int width  = args[1].i;
-	int height = args[2].i;
-	int r      = args[3].i;
-	int g      = args[4].i;
-	int b      = args[5].i;
-	int a      = args[6].i;
-
-	if (sprites[sp].used && sprites[sp].cg) {
-		cg_reinit(sprites[sp].cg, width, height, r, g, b, a);
-	} else {
-		sprites[sp].used = true;
-		sprites[sp].cg = cg_init(width, height, r, g, b, a);
-		sprite_register(&sprites[sp]);
-	}
-	hll_return(1);
-}
-
+hll_defun_inline(SP_Create, sact_SP_Create(a[0].i, a[1].i, a[2].i, a[3].i, a[4].i, a[5].i, a[6].i));
 // int SP_CreatePixelOnly(int nSP, int nWidth, int nHeight)
-hll_unimplemented(SACT2, SP_CreatePixelOnly)
+hll_unimplemented(SACT2, SP_CreatePixelOnly);
 // int SP_CreateCustom(int nSP)
-hll_unimplemented(SACT2, SP_CreateCustom)
-
+hll_unimplemented(SACT2, SP_CreateCustom);
 // int SP_Delete(int nSP)
-hll_defun(SP_Delete, args)
-{
-	struct SACT2_sprite *sp = &sprites[args[0].i];
-	if (!sp->used)
-		hll_return(0);
-	TAILQ_REMOVE(&sprite_list, sp, entry);
-	cg_free(sp->cg);
-	sp->cg = NULL;
-	hll_return(1);
-}
+hll_defun_inline(SP_Delete, sact_SP_Delete(a[0].i));
 
 // int SP_SetPos(int nSP, int nX, int nY)
 hll_defun(SP_SetPos, args)
 {
-	int sp = args[0].i;
-	sprites[sp].cg->rect.x = args[1].i;
-	sprites[sp].cg->rect.y = args[2].i;
+	struct sact_sprite *sp = sact_get_sprite(args[0].i);
+	if (!sp || !sp->cg) hll_return(1);
+	sp->rect.x = args[1].i;
+	sp->rect.y = args[2].i;
 	hll_return(1);
 }
 
 // int SP_SetX(int nSP, int nX)
 hll_defun(SP_SetX, args)
 {
-	sprites[args[0].i].cg->rect.x = args[1].i;
+	struct sact_sprite *sp = sact_get_sprite(args[0].i);
+	if (!sp || !sp->cg) hll_return(0);
+	sp->rect.x = args[1].i;
 	hll_return(1);
 }
 
 // int SP_SetY(int nSP, int nY)
 hll_defun(SP_SetY, args)
 {
-	sprites[args[0].i].cg->rect.y = args[1].i;
+	struct sact_sprite *sp = sact_get_sprite(args[0].i);
+	if (!sp || !sp->cg) hll_return(0);
+	sp->rect.y = args[1].i;
 	hll_return(1);
 }
 
 // int SP_SetZ(int nSP, int nZ)
 hll_defun(SP_SetZ, args)
 {
-	sprites[args[0].i].cg->z = args[1].i;
-	hll_return(1);
+	hll_return(sact_SP_SetZ(args[0].i, args[1].i));
 }
 
 // int SP_SetBlendRate(int nSP, int nBlendRate)
 hll_defun(SP_SetBlendRate, args)
 {
-	sprites[args[0].i].cg->color.a = args[1].i;
+	struct sact_sprite *sp = sact_get_sprite(args[0].i);
+	if (!sp || !sp->cg) hll_return(0);
+	sp->color.a = args[1].i;
 	hll_return(1);
 }
 
 // int SP_SetShow(int nSP, int nfShow)
 hll_defun(SP_SetShow, args)
 {
-	sprites[args[0].i].cg->show = !!args[1].i;
+	struct sact_sprite *sp = sact_get_sprite(args[0].i);
+	if (!sp || !sp->cg) hll_return(0);
+	sp->show = !!args[1].i;
 	hll_return(1);
 }
 
 // int SP_SetDrawMethod(int nSP, int nMethod)
-hll_unimplemented(SACT2, SP_SetDrawMethod)
+hll_unimplemented(SACT2, SP_SetDrawMethod);
 // int SP_IsUsing(int nSP)
-hll_unimplemented(SACT2, SP_IsUsing)
+hll_unimplemented(SACT2, SP_IsUsing);
 // int SP_ExistAlpha(int nSP)
-hll_unimplemented(SACT2, SP_ExistAlpha)
+hll_unimplemented(SACT2, SP_ExistAlpha);
 
 // int SP_GetPosX(int nSP)
 hll_defun(SP_GetPosX, args)
 {
-	hll_return(sprites[args[0].i].cg->rect.x);
+	struct sact_sprite *sp = sact_get_sprite(args[0].i);
+	if (!sp || !sp->cg) hll_return(0);
+	hll_return(sp->rect.x);
 }
 
 // int SP_GetPosY(int nSP)
 hll_defun(SP_GetPosY, args)
 {
-	hll_return(sprites[args[0].i].cg->rect.y);
+	struct sact_sprite *sp = sact_get_sprite(args[0].i);
+	if (!sp || !sp->cg) hll_return(0);
+	hll_return(sp->rect.y);
 }
 
 // int SP_GetWidth(int nSP)
 hll_defun(SP_GetWidth, args)
 {
-	hll_return(sprites[args[0].i].cg->rect.w);
+	struct sact_sprite *sp = sact_get_sprite(args[0].i);
+	if (!sp || !sp->cg) hll_return(0);
+	hll_return(sp->rect.w);
 }
 
 // int SP_GetHeight(int nSP)
 hll_defun(SP_GetHeight, args)
 {
-	hll_return(sprites[args[0].i].cg->rect.h);
+	struct sact_sprite *sp = sact_get_sprite(args[0].i);
+	if (!sp || !sp->cg) hll_return(0);
+	hll_return(sp->rect.h);
 }
 
 // int SP_GetZ(int nSP)
 hll_defun(SP_GetZ, args)
 {
-	hll_return(sprites[args[0].i].cg->z);
+	struct sact_sprite *sp = sact_get_sprite(args[0].i);
+	if (!sp || !sp->cg) hll_return(0);
+	hll_return(sp->z);
 }
 
 // int SP_GetBlendRate(int nSP)
 hll_defun(SP_GetBlendRate, args)
 {
-	hll_return((int)sprites[args[0].i].cg->color.a);
+	struct sact_sprite *sp = sact_get_sprite(args[0].i);
+	if (!sp || !sp->cg) hll_return(0);
+	hll_return((int)sp->color.a);
 }
 
 // int SP_GetShow(int nSP)
 hll_defun(SP_GetShow, args)
 {
-	hll_return(sprites[args[0].i].cg->show);
+	struct sact_sprite *sp = sact_get_sprite(args[0].i);
+	if (!sp || !sp->cg) hll_return(0);
+	hll_return(sp->show);
 }
 
 // int SP_GetDrawMethod(int nSP)
-hll_warn_unimplemented(SACT2, SP_GetDrawMethod, 0)
+hll_warn_unimplemented(SACT2, SP_GetDrawMethod, 0);
 // int SP_SetTextHome(int nSP, int nX, int nY)
-hll_warn_unimplemented(SACT2, SP_SetTextHome, 0)
+hll_warn_unimplemented(SACT2, SP_SetTextHome, 0);
 // int SP_SetTextLineSpace(int nSP, int nPx)
-hll_unimplemented(SACT2, SP_SetTextLineSpace)
+hll_unimplemented(SACT2, SP_SetTextLineSpace);
 // int SP_SetTextCharSpace(int nSP, int nPx)
-hll_unimplemented(SACT2, SP_SetTextCharSpace)
+hll_unimplemented(SACT2, SP_SetTextCharSpace);
 // int SP_SetTextPos(int nSP, int nX, int nY)
-hll_warn_unimplemented(SACT2, SP_SetTextPos, 0)
+hll_warn_unimplemented(SACT2, SP_SetTextPos, 0);
 // int SP_TextDraw(int nSP, string text, struct tm)
-hll_warn_unimplemented(SACT2, SP_TextDraw, 1)
+hll_warn_unimplemented(SACT2, SP_TextDraw, 1);
 // int SP_TextClear(int nSP)
-hll_warn_unimplemented(SACT2, SP_TextClear, 1)
+hll_warn_unimplemented(SACT2, SP_TextClear, 1);
 // int SP_TextHome(int nSP, int nTextSize)
-hll_warn_unimplemented(SACT2, SP_TextHome, 1)
+hll_warn_unimplemented(SACT2, SP_TextHome, 1);
 // int SP_TextNewLine(int nSP, int nTextSize)
-hll_unimplemented(SACT2, SP_TextNewLine)
+hll_unimplemented(SACT2, SP_TextNewLine);
 // int SP_TextBackSpace(int nSP)
-hll_unimplemented(SACT2, SP_TextBackSpace)
+hll_unimplemented(SACT2, SP_TextBackSpace);
 // int SP_TextCopy(int nDstSP, int nSrcSP)
-hll_unimplemented(SACT2, SP_TextCopy)
+hll_unimplemented(SACT2, SP_TextCopy);
 // int SP_GetTextHomeX(int nSP)
-hll_unimplemented(SACT2, SP_GetTextHomeX)
+hll_unimplemented(SACT2, SP_GetTextHomeX);
 // int SP_GetTextHomeY(int nSP)
-hll_unimplemented(SACT2, SP_GetTextHomeY)
+hll_unimplemented(SACT2, SP_GetTextHomeY);
 // int SP_GetTextCharSpace(int nSP)
-hll_unimplemented(SACT2, SP_GetTextCharSpace)
+hll_unimplemented(SACT2, SP_GetTextCharSpace);
 // int SP_GetTextPosX(int nSP)
-hll_unimplemented(SACT2, SP_GetTextPosX)
+hll_warn_unimplemented(SACT2, SP_GetTextPosX, 0);
 // int SP_GetTextPosY(int nSP)
-hll_unimplemented(SACT2, SP_GetTextPosY)
+hll_warn_unimplemented(SACT2, SP_GetTextPosY, 0);
 // int SP_GetTextLineSpace(int nSP)
-hll_unimplemented(SACT2, SP_GetTextLineSpace)
+hll_warn_unimplemented(SACT2, SP_GetTextLineSpace, 0);
 // int SP_IsPtIn(int nSP, int nX, int nY)
-hll_unimplemented(SACT2, SP_IsPtIn)
+hll_unimplemented(SACT2, SP_IsPtIn);
 
 // int SP_IsPtInRect(int nSP, int nX, int nY)
 hll_defun(SP_IsPtInRect, args)
 {
-	struct SACT2_sprite *sp = &sprites[args[0].i];
+	struct sact_sprite *sp = sact_get_sprite(args[0].i);
 	Point p = { .x = args[1].i, .y = args[2].i };
-
-	if (!sp->used)
-		hll_return(0);
-	hll_return(!!SDL_PointInRect(&p, &sp->cg->rect));
+	if (!sp || !sp->cg) hll_return(0);
+	hll_return(!!SDL_PointInRect(&p, &sp->rect));
 }
 
 // int GAME_MSG_GetNumof(void)
-hll_unimplemented(SACT2, GAME_MSG_GetNumof)
+hll_unimplemented(SACT2, GAME_MSG_GetNumof);
 // void GAME_MSG_Get(int nIndex, ref string text)
-hll_unimplemented(SACT2, GAME_MSG_Get)
+hll_unimplemented(SACT2, GAME_MSG_Get);
 // void IntToZenkaku(ref string s, int nValue, int nFigures, int nfZeroPadding)
-hll_unimplemented(SACT2, IntToZenkaku)
+hll_unimplemented(SACT2, IntToZenkaku);
 // void IntToHankaku(ref string s, int nValue, int nFigures, int nfZeroPadding)
-hll_unimplemented(SACT2, IntToHankaku)
+hll_unimplemented(SACT2, IntToHankaku);
 // int StringPopFront(ref string sDst, ref string sSrc)
-hll_unimplemented(SACT2, StringPopFront)
+hll_unimplemented(SACT2, StringPopFront);
 
 // int Mouse_GetPos(ref int pnX, ref int pnY)
 hll_defun(Mouse_GetPos, args)
@@ -351,27 +260,27 @@ hll_defun(Mouse_GetPos, args)
 }
 
 // int Mouse_SetPos(int nX, int nY)
-hll_warn_unimplemented(SACT2, Mouse_SetPos, 1)
+hll_warn_unimplemented(SACT2, Mouse_SetPos, 1);
 // void Mouse_ClearWheel(void)
-hll_warn_unimplemented(SACT2, Mouse_ClearWheel, 0)
+hll_warn_unimplemented(SACT2, Mouse_ClearWheel, 0);
 
 // void Mouse_GetWheel(ref int pnForward, ref int pnBack)
 hll_defun(Mouse_GetWheel, args)
 {
-	hll_unimplemented_warning(SACT2, Mouse_GetWheel);
+	//hll_unimplemented_warning(SACT2, Mouse_GetWheel);
 	*args[0].iref = 0;
 	*args[1].iref = 0;
 	hll_return(0);
 }
 
 // void Joypad_ClearKeyDownFlag(int nNum)
-hll_warn_unimplemented(SACT2, Joypad_ClearKeyDownFlag, 0)
+hll_warn_unimplemented(SACT2, Joypad_ClearKeyDownFlag, 0);
 // int Joypad_IsKeyDown(int nNum, int nKey)
-hll_unimplemented(SACT2, Joypad_IsKeyDown)
+hll_unimplemented(SACT2, Joypad_IsKeyDown);
 // int Joypad_GetNumof(void)
-hll_unimplemented(SACT2, Joypad_GetNumof)
+hll_unimplemented(SACT2, Joypad_GetNumof);
 // void JoypadQuake_Set(int nNum, int nType, int nMagnitude)
-hll_unimplemented(SACT2, JoypadQuake_Set)
+hll_unimplemented(SACT2, JoypadQuake_Set);
 
 // bool Joypad_GetAnalogStickStatus(int nNum, int nType, ref float pfDegree, ref float pfPower)
 hll_defun(Joypad_GetAnalogStickStatus, args)
@@ -385,7 +294,7 @@ hll_defun(Joypad_GetAnalogStickStatus, args)
 // bool Joypad_GetDigitalStickStatus(int nNum, int nType, ref bool pbLeft, ref bool pbRight, ref bool pbUp, ref bool pbDown)
 hll_defun(Joypad_GetDigitalStickStatus, args)
 {
-	hll_unimplemented_warning(SACT2, Joypad_GetDigitalStickStatus);
+	//hll_unimplemented_warning(SACT2, Joypad_GetDigitalStickStatus);
 	*args[2].iref = 0;
 	*args[3].iref = 0;
 	*args[4].iref = 0;
@@ -394,170 +303,135 @@ hll_defun(Joypad_GetDigitalStickStatus, args)
 }
 
 // int Key_ClearFlag(void)
-hll_warn_unimplemented(SACT2, Key_ClearFlag, 1)
-
+hll_defun_inline(Key_ClearFlag, (key_clear_flag(), 1));
 // int Key_IsDown(int nKeyCode)
-hll_defun(Key_IsDown, args)
-{
-	hll_return(key_is_down(args[0].i));
-}
-
+hll_defun_inline(Key_IsDown, key_is_down(a[0].i));
 // int Timer_Get(void)
-hll_defun(Timer_Get, _)
-{
-	hll_return(vm_time());
-}
-
+hll_defun_inline(Timer_Get, vm_time());
 // int CG_IsExist(int nCG)
-hll_defun(CG_IsExist, args)
-{
-	hll_return(cg_exists(args[0].i));
-}
-
+hll_defun_inline(CG_IsExist, cg_exists(a[0].i));
 // int CG_GetMetrics(int nCG, ref struct cm)
-hll_unimplemented(SACT2, CG_GetMetrics)
+hll_unimplemented(SACT2, CG_GetMetrics);
 // int CSV_Load(string pIStringFileName)
-hll_unimplemented(SACT2, CSV_Load)
+hll_unimplemented(SACT2, CSV_Load);
 // int CSV_Save(void)
-hll_unimplemented(SACT2, CSV_Save)
+hll_unimplemented(SACT2, CSV_Save);
 // int CSV_SaveAs(string pIStringFileName)
-hll_unimplemented(SACT2, CSV_SaveAs)
+hll_unimplemented(SACT2, CSV_SaveAs);
 // int CSV_CountLines(void)
-hll_unimplemented(SACT2, CSV_CountLines)
+hll_unimplemented(SACT2, CSV_CountLines);
 // int CSV_CountColumns(void)
-hll_unimplemented(SACT2, CSV_CountColumns)
+hll_unimplemented(SACT2, CSV_CountColumns);
 // void CSV_Get(ref string pIString, int nLine, int nColumn)
-hll_unimplemented(SACT2, CSV_Get)
+hll_unimplemented(SACT2, CSV_Get);
 // int CSV_Set(int nLine, int nColumn, string pIStringData)
-hll_unimplemented(SACT2, CSV_Set)
+hll_unimplemented(SACT2, CSV_Set);
 // int CSV_GetInt(int nLine, int nColumn)
-hll_unimplemented(SACT2, CSV_GetInt)
+hll_unimplemented(SACT2, CSV_GetInt);
 // void CSV_SetInt(int nLine, int nColumn, int nData)
-hll_unimplemented(SACT2, CSV_SetInt)
+hll_unimplemented(SACT2, CSV_SetInt);
 // void CSV_Realloc(int nLines, int nColumns)
-hll_unimplemented(SACT2, CSV_Realloc)
-
+hll_unimplemented(SACT2, CSV_Realloc);
 // int Music_IsExist(int nNum)
-hll_warn_unimplemented(SACT2, Music_IsExist, 1)
-
+hll_warn_unimplemented(SACT2, Music_IsExist, 1);
 // int Music_Prepare(int nCh, int nNum)
-hll_warn_unimplemented(SACT2, Music_Prepare, 1)
-
+hll_warn_unimplemented(SACT2, Music_Prepare, 1);
 // int Music_Unprepare(int nCh)
-hll_warn_unimplemented(SACT2, Music_Unprepare, 1)
-
+hll_warn_unimplemented(SACT2, Music_Unprepare, 1);
 // int Music_Play(int nCh)
-hll_warn_unimplemented(SACT2, Music_Play, 1)
-
+hll_warn_unimplemented(SACT2, Music_Play, 1);
 // int Music_Stop(int nCh)
-hll_warn_unimplemented(SACT2, Music_Stop, 1)
-
+hll_warn_unimplemented(SACT2, Music_Stop, 1);
 // int Music_IsPlay(int nCh)
-hll_warn_unimplemented(SACT2, Music_IsPlay, 1)
-
+hll_warn_unimplemented(SACT2, Music_IsPlay, 1);
 // int Music_SetLoopCount(int nCh, int nCount)
-hll_warn_unimplemented(SACT2, Music_SetLoopCount, 1)
-
+hll_warn_unimplemented(SACT2, Music_SetLoopCount, 1);
 // int Music_GetLoopCount(int nCh)
-hll_warn_unimplemented(SACT2, Music_GetLoopCount, 1)
-
+hll_warn_unimplemented(SACT2, Music_GetLoopCount, 1);
 // int Music_SetLoopStartPos(int nCh, int dwPos)
-hll_warn_unimplemented(SACT2, Music_SetLoopStartPos, 1)
-
+hll_warn_unimplemented(SACT2, Music_SetLoopStartPos, 1);
 // int Music_SetLoopEndPos(int nCh, int dwPos)
-hll_warn_unimplemented(SACT2, Music_SetLoopEndPos, 1)
-
+hll_warn_unimplemented(SACT2, Music_SetLoopEndPos, 1);
 // int Music_Fade(int nCh, int nTime, int nVolume, int bStop)
-hll_warn_unimplemented(SACT2, Music_Fade, 1)
-
+hll_warn_unimplemented(SACT2, Music_Fade, 1);
 // int Music_StopFade(int nCh)
-hll_warn_unimplemented(SACT2, Music_StopFade, 1)
-
+hll_warn_unimplemented(SACT2, Music_StopFade, 1);
 // int Music_IsFade(int nCh)
-hll_warn_unimplemented(SACT2, Music_IsFade, 1)
-
+hll_warn_unimplemented(SACT2, Music_IsFade, 1);
 // int Music_Pause(int nCh)
-hll_warn_unimplemented(SACT2, Music_Pause, 1)
-
+hll_warn_unimplemented(SACT2, Music_Pause, 1);
 // int Music_Restart(int nCh)
-hll_warn_unimplemented(SACT2, Music_Restart, 1)
-
+hll_warn_unimplemented(SACT2, Music_Restart, 1);
 // int Music_IsPause(int nCh)
-hll_warn_unimplemented(SACT2, Music_IsPause, 1)
-
+hll_warn_unimplemented(SACT2, Music_IsPause, 1);
 // int Music_GetPos(int nCh)
-hll_warn_unimplemented(SACT2, Music_GetPos, 1)
-
+hll_warn_unimplemented(SACT2, Music_GetPos, 1);
 // int Music_GetLength(int nCh)
-hll_warn_unimplemented(SACT2, Music_GetLength, 1)
-
+hll_warn_unimplemented(SACT2, Music_GetLength, 1);
 // int Music_GetSamplePos(int nCh)
-hll_warn_unimplemented(SACT2, Music_GetSamplePos, 1)
-
+hll_warn_unimplemented(SACT2, Music_GetSamplePos, 1);
 // int Music_GetSampleLength(int nCh)
-hll_warn_unimplemented(SACT2, Music_GetSampleLength, 1)
-
+hll_warn_unimplemented(SACT2, Music_GetSampleLength, 1);
 // int Music_Seek(int nCh, int dwPos)
-hll_warn_unimplemented(SACT2, Music_Seek, 1)
-
+hll_warn_unimplemented(SACT2, Music_Seek, 1);
 // int Sound_IsExist(int nNum)
-hll_unimplemented(SACT2, Sound_IsExist)
+hll_unimplemented(SACT2, Sound_IsExist);
 // int Sound_GetUnuseChannel(void)
-hll_unimplemented(SACT2, Sound_GetUnuseChannel)
+hll_unimplemented(SACT2, Sound_GetUnuseChannel);
 // int Sound_Prepare(int nCh, int nNum)
-hll_unimplemented(SACT2, Sound_Prepare)
+hll_unimplemented(SACT2, Sound_Prepare);
 // int Sound_Unprepare(int nCh)
-hll_unimplemented(SACT2, Sound_Unprepare)
+hll_unimplemented(SACT2, Sound_Unprepare);
 // int Sound_Play(int nCh)
-hll_unimplemented(SACT2, Sound_Play)
+hll_unimplemented(SACT2, Sound_Play);
 // int Sound_Stop(int nCh)
-hll_unimplemented(SACT2, Sound_Stop)
+hll_unimplemented(SACT2, Sound_Stop);
 // int Sound_IsPlay(int nCh)
-hll_unimplemented(SACT2, Sound_IsPlay)
+hll_unimplemented(SACT2, Sound_IsPlay);
 // int Sound_SetLoopCount(int nCh, int nCount)
-hll_unimplemented(SACT2, Sound_SetLoopCount)
+hll_unimplemented(SACT2, Sound_SetLoopCount);
 // int Sound_GetLoopCount(int nCh)
-hll_unimplemented(SACT2, Sound_GetLoopCount)
+hll_unimplemented(SACT2, Sound_GetLoopCount);
 // int Sound_Fade(int nCh, int nTime, int nVolume, int bStop)
-hll_unimplemented(SACT2, Sound_Fade)
+hll_unimplemented(SACT2, Sound_Fade);
 // int Sound_StopFade(int nCh)
-hll_unimplemented(SACT2, Sound_StopFade)
+hll_unimplemented(SACT2, Sound_StopFade);
 // int Sound_IsFade(int nCh)
-hll_unimplemented(SACT2, Sound_IsFade)
+hll_unimplemented(SACT2, Sound_IsFade);
 // int Sound_GetPos(int nCh)
-hll_unimplemented(SACT2, Sound_GetPos)
+hll_unimplemented(SACT2, Sound_GetPos);
 // int Sound_GetLength(int nCh)
-hll_unimplemented(SACT2, Sound_GetLength)
+hll_unimplemented(SACT2, Sound_GetLength);
 // int Sound_ReverseLR(int nCh)
-hll_unimplemented(SACT2, Sound_ReverseLR)
+hll_unimplemented(SACT2, Sound_ReverseLR);
 // int Sound_GetVolume(int nCh)
-hll_unimplemented(SACT2, Sound_GetVolume)
+hll_unimplemented(SACT2, Sound_GetVolume);
 // int Sound_GetTimeLength(int nCh)
-hll_unimplemented(SACT2, Sound_GetTimeLength)
+hll_unimplemented(SACT2, Sound_GetTimeLength);
 // int Sound_GetGroupNum(int nCh)
-hll_unimplemented(SACT2, Sound_GetGroupNum)
+hll_unimplemented(SACT2, Sound_GetGroupNum);
 // bool Sound_PrepareFromFile(int nCh, string szFileName)
-hll_unimplemented(SACT2, Sound_PrepareFromFile)
+hll_unimplemented(SACT2, Sound_PrepareFromFile);
 // void System_GetDate(ref int pnYear, ref int pnMonth, ref int pnDay, ref int pnDayOfWeek)
-hll_unimplemented(SACT2, System_GetDate)
+hll_unimplemented(SACT2, System_GetDate);
 // void System_GetTime(ref int pnHour, ref int pnMinute, ref int pnSecond, ref int pnMilliSeconds)
-hll_unimplemented(SACT2, System_GetTime)
+hll_unimplemented(SACT2, System_GetTime);
 // void CG_RotateRGB(int nDest, int nDx, int nDy, int nWidth, int nHeight, int nRotateType)
-hll_unimplemented(SACT2, CG_RotateRGB)
+hll_unimplemented(SACT2, CG_RotateRGB);
 // void CG_BlendAMapBin(int nDest, int nDx, int nDy, int nSrc, int nSx, int nSy, int nWidth, int nHeight, int nBorder)
-hll_unimplemented(SACT2, CG_BlendAMapBin)
+hll_unimplemented(SACT2, CG_BlendAMapBin);
 // void Debug_Pause(void)
-hll_unimplemented(SACT2, Debug_Pause)
+hll_unimplemented(SACT2, Debug_Pause);
 // void Debug_GetFuncStack(ref string sz, int nNest)
-hll_unimplemented(SACT2, Debug_GetFuncStack)
+hll_unimplemented(SACT2, Debug_GetFuncStack);
 // int SP_GetAMapValue(int nSP, int nX, int nY)
-hll_unimplemented(SACT2, SP_GetAMapValue)
+hll_unimplemented(SACT2, SP_GetAMapValue);
 // bool SP_GetPixelValue(int nSP, int nX, int nY, ref int pnR, ref int pnG, ref int pnB)
-hll_unimplemented(SACT2, SP_GetPixelValue)
+hll_unimplemented(SACT2, SP_GetPixelValue);
 // int SP_SetBrightness(int nSP, int nBrightness)
-hll_unimplemented(SACT2, SP_SetBrightness)
+hll_unimplemented(SACT2, SP_SetBrightness);
 // int SP_GetBrightness(int nSP)
-hll_unimplemented(SACT2, SP_GetBrightness)
+hll_unimplemented(SACT2, SP_GetBrightness);
 
 hll_deflib(SACT2) {
 	hll_export(Init),
diff --git a/hll/hll.h b/hll/hll.h
index 16fb265..adcfca2 100644
--- a/hll/hll.h
+++ b/hll/hll.h
@@ -33,6 +33,9 @@
 	};								\
 	static union vm_value _hllfun_ ## fname(possibly_unused union vm_value *args)
 
+#define hll_defun_inline(fname, expr)			\
+	hll_defun(fname, a) { hll_return(expr); }
+
 #define hll_unimplemented(libname, fname)				\
 	hll_defun(fname, args) {					\
 		VM_ERROR("Unimplemented HLL function: " #libname "." #fname); \
diff --git a/input.c b/input.c
index b3d1f9b..15e49e2 100644
--- a/input.c
+++ b/input.c
@@ -25,24 +25,33 @@ static enum sact_keycode sdl_keytable[];
 bool mouse_focus = true;
 bool keyboard_focus = true;
 
-static SDL_Scancode sact_to_sdl_button(enum sact_keycode code)
+static enum sact_keycode sdl_to_sact_button(int button)
 {
-	switch (code) {
-	case VK_LBUTTON: return SDL_BUTTON_LEFT;
-	case VK_RBUTTON: return SDL_BUTTON_RIGHT;
-	case VK_MBUTTON: return SDL_BUTTON_MIDDLE;
-	default:         return 0;
+	switch (button) {
+	case SDL_BUTTON_LEFT:   return VK_LBUTTON;
+	case SDL_BUTTON_RIGHT:  return VK_RBUTTON;
+	case SDL_BUTTON_MIDDLE: return VK_MBUTTON;
+	default:                return 0;
 	}
 }
 
 bool key_is_down(enum sact_keycode code)
 {
-	int button = sact_to_sdl_button(code);
-	if (button)
-		return SDL_GetMouseState(NULL, NULL) & SDL_BUTTON(button);
 	return key_state[code];
 }
 
+void key_clear_flag(void)
+{
+	for (int i = 0; i < VK_NR_KEYCODES; i++) {
+		key_state[i] = false;
+	}
+}
+
+void mouse_get_pos(int *x, int *y)
+{
+	SDL_GetMouseState(x, y);
+}
+
 static void key_event(SDL_KeyboardEvent *e, bool pressed)
 {
 	enum sact_keycode code = sdl_keytable[e->keysym.scancode];
@@ -50,9 +59,11 @@ static void key_event(SDL_KeyboardEvent *e, bool pressed)
 		key_state[code] = pressed;
 }
 
-void mouse_get_pos(int *x, int *y)
+static void mouse_event(SDL_MouseButtonEvent *e)
 {
-	SDL_GetMouseState(x, y);
+	enum sact_keycode code = sdl_to_sact_button(e->button);
+	if (code)
+		key_state[code] = e->state == SDL_PRESSED;
 }
 
 void handle_events(void)
@@ -88,6 +99,10 @@ void handle_events(void)
 		case SDL_KEYUP:
 			key_event(&e.key, false);
 			break;
+		case SDL_MOUSEBUTTONUP:
+		case SDL_MOUSEBUTTONDOWN:
+			mouse_event(&e.button);
+			break;
 		default:
 			break;
 		}
diff --git a/input.h b/input.h
index 3f5111c..3c77d8b 100644
--- a/input.h
+++ b/input.h
@@ -139,6 +139,7 @@ bool keyboard_focus;
 
 void handle_events(void);
 bool key_is_down(enum sact_keycode code);
+void key_clear_flag(void);
 void mouse_get_pos(int *x, int *y);
 
 #endif /* SYSTEM4_INPUT_H */
diff --git a/meson.build b/meson.build
index 81158be..ca5825c 100644
--- a/meson.build
+++ b/meson.build
@@ -12,6 +12,7 @@ xsystem4 = ['ald.c',
             'ini.c',
             'input.c',
             'page.c',
+            'sact_graphics.c',
             'sdl_draw.c',
             'sdl_video.c',
             'system4.c',
diff --git a/qnt.c b/qnt.c
index 9751a1a..8c5c170 100644
--- a/qnt.c
+++ b/qnt.c
@@ -246,7 +246,7 @@ bool qnt_checkfmt(uint8_t *data)
  *
  *   return: extracted image data and information
 */
-void qnt_extract(struct cg *cg, uint8_t *data)
+SDL_Surface *qnt_extract(uint8_t *data)
 {
 	// FIXME: endianness?
 	uint32_t amask = 0x0;
@@ -257,38 +257,28 @@ void qnt_extract(struct cg *cg, uint8_t *data)
 	uint8_t *pixels = malloc(sizeof(uint8_t) * ((qnt->width+10) * (qnt->height+10) * 3));
 	extract_pixel(qnt, pixels, data + qnt->hdr_size);
 
+	if (!qnt->alpha_size)
+		return SDL_CreateRGBSurfaceFrom(pixels, qnt->width, qnt->height, 24, qnt->width * 3,
+						rmask, gmask, bmask, amask);
+
 	// combine color/alpha data
-	if (qnt->alpha_size) {
-		uint8_t *alpha = malloc(sizeof(uint8_t) * ((qnt->width+10) * (qnt->height+10)));
-		uint8_t *tmp = malloc((qnt->width+10) * (qnt->height+10) * 4);
-		extract_alpha(qnt, alpha, data + qnt->hdr_size + qnt->pixel_size);
-		for (int src_i = 0, dst_i = 0, p = 0; p < qnt->width * qnt->height; p++) {
-			tmp[dst_i++] = alpha[p];
-			tmp[dst_i++] = pixels[src_i++];
-			tmp[dst_i++] = pixels[src_i++];
-			tmp[dst_i++] = pixels[src_i++];
-		}
-		free(alpha);
-		free(pixels);
-		pixels = tmp;
-		amask = 0xFF;
-		rmask = 0xFF00;
-		gmask = 0xFF0000;
-		bmask = 0xFF000000;
-
-		cg->s = SDL_CreateRGBSurfaceFrom(pixels, qnt->width, qnt->height, 32, qnt->width * 4,
-						 rmask, gmask, bmask, amask);
-	} else {
-		// create SDL surface
-		cg->s = SDL_CreateRGBSurfaceFrom(pixels, qnt->width, qnt->height, 24, qnt->width * 3,
-						 rmask, gmask, bmask, amask);
+	uint8_t *alpha = malloc(sizeof(uint8_t) * ((qnt->width+10) * (qnt->height+10)));
+	uint8_t *tmp = malloc((qnt->width+10) * (qnt->height+10) * 4);
+	extract_alpha(qnt, alpha, data + qnt->hdr_size + qnt->pixel_size);
+	for (int src_i = 0, dst_i = 0, p = 0; p < qnt->width * qnt->height; p++) {
+		tmp[dst_i++] = alpha[p];
+		tmp[dst_i++] = pixels[src_i++];
+		tmp[dst_i++] = pixels[src_i++];
+		tmp[dst_i++] = pixels[src_i++];
 	}
-	if (!cg->s)
-		ERROR("Creating surface failed: %s", SDL_GetError());
+	free(alpha);
+	free(pixels);
+	pixels = tmp;
+	amask = 0xFF;
+	rmask = 0xFF00;
+	gmask = 0xFF0000;
+	bmask = 0xFF000000;
 
-	cg->type   = ALCG_QNT;
-	cg->rect.x = qnt->x0; // ???
-	cg->rect.y = qnt->y0; // ???
-	cg->rect.w = qnt->width;
-	cg->rect.h = qnt->height;
+	return SDL_CreateRGBSurfaceFrom(pixels, qnt->width, qnt->height, 32, qnt->width * 4,
+					rmask, gmask, bmask, amask);
 }
diff --git a/qnt.h b/qnt.h
index 9357e44..1065f55 100644
--- a/qnt.h
+++ b/qnt.h
@@ -28,6 +28,7 @@
 
 #include <stdbool.h>
 #include <stdint.h>
+#include <SDL.h>
 #include "cg.h"
 
 struct qnt_header {
@@ -43,6 +44,6 @@ struct qnt_header {
 };
 
 bool qnt_checkfmt(uint8_t *data);
-void qnt_extract(struct cg *cg, uint8_t *data);
+SDL_Surface *qnt_extract(uint8_t *data);
 
 #endif /* __QNT_H__ */
diff --git a/sact.h b/sact.h
new file mode 100644
index 0000000..7923486
--- /dev/null
+++ b/sact.h
@@ -0,0 +1,47 @@
+/* Copyright (C) 2019 Nunuhara Cabbage <nunuhara@haniwa.technology>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <http://gnu.org/licenses/>.
+ */
+
+#ifndef SYSTEM4_SACT_H
+#define SYSTEM4_SACT_H
+
+#include <stdbool.h>
+#include <SDL.h>
+#include "queue.h"
+#include "graphics.h"
+
+struct cg;
+
+struct sact_sprite {
+	TAILQ_ENTRY(sact_sprite) entry;
+	struct cg *cg;
+	SDL_Color color;
+	Rectangle rect;
+	int z;
+	bool show;
+};
+
+struct sact_sprite *sact_get_sprite(int sp);
+
+int sact_Init(void);
+int sact_Update(void);
+int sact_SP_GetUnuseNum(int min);
+int sact_SP_GetMaxZ(void);
+int sact_SP_SetCG(int sp, int cg);
+int sact_SP_Create(int sp, int width, int height, int r, int g, int b, int a);
+int sact_SP_Delete(int sp);
+int sact_SP_SetZ(int sp, int z);
+
+#endif /* SYSTEM4_SACT_H */
diff --git a/sact_graphics.c b/sact_graphics.c
new file mode 100644
index 0000000..38876e6
--- /dev/null
+++ b/sact_graphics.c
@@ -0,0 +1,153 @@
+/* Copyright (C) 2019 Nunuhara Cabbage <nunuhara@haniwa.technology>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <http://gnu.org/licenses/>.
+ */
+
+#include "system4.h"
+#include "sact.h"
+#include "cg.h"
+#include "input.h"
+#include "sdl_core.h"
+
+static struct sact_sprite **sprites = NULL;
+static int nr_sprites = 0;
+
+TAILQ_HEAD(listhead, sact_sprite) sprite_list =
+	TAILQ_HEAD_INITIALIZER(sprite_list);
+
+struct sact_sprite *sact_get_sprite(int sp)
+{
+	if (sp >= nr_sprites)
+		return NULL;
+	return sprites[sp];
+}
+
+static struct sact_sprite *alloc_sprite(int sp)
+{
+	sprites[sp] = xcalloc(1, sizeof(struct sact_sprite));
+	return sprites[sp];
+}
+
+static void sprite_register(struct sact_sprite *sp)
+{
+	struct sact_sprite *p;
+	TAILQ_FOREACH(p, &sprite_list, entry) {
+		if (p->z > sp->z) {
+			TAILQ_INSERT_BEFORE(p, sp, entry);
+			return;
+		}
+	}
+	TAILQ_INSERT_TAIL(&sprite_list, sp, entry);
+}
+
+static void sprite_unregister(struct sact_sprite *sp)
+{
+	TAILQ_REMOVE(&sprite_list, sp, entry);
+}
+
+int sact_Init(void)
+{
+	sdl_initialize();
+	return 1;
+}
+
+int sact_Update(void)
+{
+	handle_events();
+	struct sact_sprite *p;
+	TAILQ_FOREACH(p, &sprite_list, entry) {
+		if (!p->show)
+			continue;
+		if (!p->cg->s)
+			p->cg->s = sdl_make_rectangle(p->rect.w, p->rect.h, &p->color);
+		sdl_draw_cg(p->cg, &p->rect);
+	}
+	sdl_update_screen();
+	return 1;
+}
+
+int sact_SP_GetUnuseNum(int min)
+{
+	for (int i = min; i < nr_sprites; i++) {
+		if (!sprites[i])
+			return i;
+	}
+
+	int n = max(min, nr_sprites);
+	nr_sprites = n + 256;
+	sprites = xrealloc(sprites, sizeof(struct sact_sprite*) * nr_sprites);
+	for (int i = n; i < nr_sprites; i++)
+		sprites[i] = NULL;
+	return n;
+}
+
+int sact_SP_GetMaxZ(void)
+{
+	if (TAILQ_EMPTY(&sprite_list))
+		return 0;
+	return TAILQ_LAST(&sprite_list, listhead)->z;
+}
+
+int sact_SP_SetCG(int sp_no, int cg_no)
+{
+	struct sact_sprite *sp = sact_get_sprite(sp_no);
+	if (!sp || !cg_load(sp->cg, cg_no - 1))
+		return 0;
+	sp->rect.w = sp->cg->s->w;
+	sp->rect.h = sp->cg->s->h;
+	return 1;
+
+}
+
+int sact_SP_Create(int sp_no, int width, int height, int r, int g, int b, int a)
+{
+	struct sact_sprite *sp = sact_get_sprite(sp_no);
+
+	if (!sp) {
+		sp = alloc_sprite(sp_no);
+	}
+
+	sp->color = (SDL_Color) { .r = r, .g = g, .b = b, .a = a };
+	sp->rect.w = width;
+	sp->rect.h = height;
+	if (sp->cg) {
+		cg_reinit(sp->cg);
+	} else {
+		sp->cg = cg_init();
+		sprite_register(sp);
+	}
+	return 1;
+}
+
+int sact_SP_Delete(int sp_no)
+{
+	struct sact_sprite *sp = sact_get_sprite(sp_no);
+	if (!sp) return 0;
+	sprite_unregister(sp);
+	cg_free(sp->cg);
+	sp->cg = NULL;
+	return 1;
+}
+
+int sact_SP_SetZ(int sp_no, int z)
+{
+	struct sact_sprite *sp = sact_get_sprite(sp_no);
+	if (!sp || !sp->cg) return 0;
+	sprite_unregister(sp);
+	sp->z = z;
+	sprite_register(sp);
+	return 1;
+
+}
+
diff --git a/sdl_core.h b/sdl_core.h
index d831a7d..a407eb9 100644
--- a/sdl_core.h
+++ b/sdl_core.h
@@ -31,6 +31,7 @@ void sdl_set_window_size(int x, int y, int w, int h);
 void sdl_fullscreen(bool on);
 
 void sdl_update_screen(void);
-void sdl_draw_cg(struct cg *cg);
+void sdl_draw_cg(struct cg *cg, Rectangle *dst);
+SDL_Surface *sdl_make_rectangle(int w, int h, SDL_Color *color);
 
 #endif /* SYSTEM4_SDL_CORE_H */
diff --git a/sdl_draw.c b/sdl_draw.c
index 33a679d..9640590 100644
--- a/sdl_draw.c
+++ b/sdl_draw.c
@@ -36,7 +36,7 @@ void sdl_update_screen(void)
 	sdl.dirty = false;
 }
 
-static SDL_Surface *make_rectangle(int w, int h, SDL_Color *color)
+SDL_Surface *sdl_make_rectangle(int w, int h, SDL_Color *color)
 {
 	Rectangle rect = { .x = 0, .y = 0, .w = w, .h = w };
 	SDL_Surface *s = SDL_CreateRGBSurface(0, w, h, 32, 0xFF00, 0xFF0000, 0xFF000000, 0xFF);
@@ -69,11 +69,9 @@ void sdl_draw_rectangle(Rectangle *_rect, int pixels, uint8_t r, uint8_t g, uint
 	sdl.dirty = true;
 }
 
-void sdl_draw_cg(struct cg *cg)
+void sdl_draw_cg(struct cg *cg, Rectangle *dst)
 {
-	Rectangle src = { .x = 0, .y = 0, .w = cg->rect.w, .h = cg->rect.h };
-	if (!cg->s)
-		cg->s = make_rectangle(cg->rect.w, cg->rect.h, &cg->color);
-	SDL_BlitSurface(cg->s, &src, sdl.display, &cg->rect);
+	Rectangle src = { .x = 0, .y = 0, .w = cg->s->w, .h = cg->s->h };
+	SDL_BlitSurface(cg->s, &src, sdl.display, dst);
 	sdl.dirty = true;
 }