--- a/window/picture.cc
+++ b/window/picture.cc
@@ -41,10 +41,9 @@
 
 using namespace std;
 
-int print_blit = 0;
 /* render.cc */
 void DSurfaceBlitAlpha(Surface* src_o, const Rect& srcrect_o, Surface* dst_o, const Rect& dstrect_o, const unsigned char* alpha, const Rect& alpharect);
-void DSurfaceBlitSaturate(Surface* src_o, const Rect& srcrect, Surface* dst_o, const Rect& dstrect, unsigned char alpha);
+void DSurfaceBlitAdd(Surface* src_o, const Rect& srcrect, Surface* dst_o, const Rect& dstrect, unsigned char alpha);
 void DSurfaceBlitMultiply(Surface* src_o, const Rect& srcrect, Surface* dst_o, const Rect& dstrect);
 void DSurfaceFill(Surface* src, const Rect& rect, int r, int g, int b, int a=0xff); // クリア
 #if 0 /* DEBUG */
@@ -180,13 +179,9 @@ void PicBase::ExecReBlit(const Rect& rpo
 	Rect rpos = rpos_c;
 	Rect abs_r = QueryAbsPos(rpos);
 	Rect ppos = parent_pos(rpos);
-if(print_blit) fprintf(stderr,"back.");
 	if (parent) parent->BlitBack(z_pos, ppos);
-if(print_blit) fprintf(stderr,"self.");
 	if (!is_hidden_now) Blit(rpos);
-if(print_blit) fprintf(stderr,"front.");
 	if (parent) parent->BlitFront(z_pos, ppos);
-if(print_blit) fprintf(stderr,"end.");
 }
 
 void PicBase::ZMove(PicBase* move_to) {
@@ -324,7 +319,7 @@ void PicBase::SetSurfaceAlpha(const unsi
 void PicBase::SetSurfaceColorKey(int r, int g, int b) {
 	surface_alpha = 0;
 	surface_alpha_rect = Rect(0,0);
-	attribute &= ~(BLIT_SATURATE | BLIT_MULTIPLY);
+	attribute &= ~(BLIT_ADD | BLIT_MULTIPLY);
 	if (surface_own) {
 		int key = SDL_MapRGB( ((SDL_Surface*)surface_own)->format, r, g, b);
 		key |= 0xff000000;
@@ -402,7 +397,7 @@ void PicBase::SetSurface(Surface* new_su
 	if (surface_own != NULL && (attribute & SURFACE_FREE)) {
 		root->DeleteSurface(surface_own);
 	}
-	attribute &= ~(SURFACE_FREE | BLIT_SATURATE | BLIT_MULTIPLY | NO_PICTURE | SOLID);
+	attribute &= ~(SURFACE_FREE | BLIT_ADD | BLIT_MULTIPLY | NO_PICTURE | SOLID);
 	attribute |= new_attr;
 	surface_own = new_surface;
 	surface_x = x;
@@ -469,9 +464,9 @@ void PicBase::SetClipArea(const Rect& r)
 }
 
 void PicBase::SetSurfaceAttribute(int new_attribute) {
-	attribute &= ~(BLIT_SATURATE | BLIT_MULTIPLY);
-	attribute |= new_attribute & (BLIT_SATURATE | BLIT_MULTIPLY);
-	if (new_attribute & (BLIT_SATURATE | BLIT_MULTIPLY)) {
+	attribute &= ~(BLIT_ADD | BLIT_MULTIPLY);
+	attribute |= new_attribute & (BLIT_ADD | BLIT_MULTIPLY);
+	if (new_attribute & (BLIT_ADD | BLIT_MULTIPLY)) {
 		rel_solid_area = Rect(0,0);
 	}
 }
@@ -539,19 +534,16 @@ void PicContainer::BlitBack(iterator z, 
 		Rect cpos = child_pos(rpos, *z);
 		Rect apos = (*z)->QueryAbsPos(cpos);
 		Rect draw_rpos = (*z)->parent_pos(cpos);
-if(print_blit) fprintf(stderr,"cahce.");
 		root->BlitSurface(surface_back, draw_rpos, root->surface, apos);
 		goto self_redraw;
 	}
 parent_redraw:
 	if (parent) {
 		Rect ppos = parent_pos(rpos);
-if(print_blit) fprintf(stderr,"parent-back.");
 		parent->BlitBack(z_pos, ppos);
 	}
 	if (is_hidden_now) return;
 self_redraw:
-if(print_blit) fprintf(stderr,"back-self.");
 	BlitSelf(rpos); // 子は描画せず、自分だけ描画
 children_redraw:
 	for (; it != z; it++) {
@@ -564,10 +556,8 @@ children_redraw:
 }
 
 void PicContainer::BlitChildren(Rect rpos) {
-if (print_blit) fprintf(stderr,"bc.");
 	iterator end = children.end();
 	for (iterator it = children.begin(); it != end; it++) {
-if ( (*it)->is_hidden_now) if(print_blit) fprintf(stderr,"bch %p;",*it);
 		if ( (*it)->is_hidden_now) continue;
 		if ( (*it)->rel_pos.is_crossed(rpos)) {
 			Rect cpos = child_pos(rpos, *it);
@@ -601,7 +591,6 @@ void PicContainer::BlitSelf(Rect rpos) {
 	if (rpos.empty()) return;
 	Rect apos = QueryAbsPos(rpos);
 	// 必要に応じて保存、描画
-if(print_blit) fprintf(stderr,"self-back.");
 	if (attribute & CACHE_BACK) root->BlitSurface(root->surface, apos, surface_back, rpos);
 	if (! (attribute & NO_PICTURE)) {
 		rpos.rmove(surface_x, surface_y);
@@ -610,7 +599,6 @@ if(print_blit) fprintf(stderr,"self-back
 			clip.rmove(rpos.lx, rpos.ty);
 			rpos.intersect(clip);
 		}
-if(print_blit) fprintf(stderr,"self-blit.");
 		root->BlitSurface(surface_own, rpos, surface_alpha, surface_alpha_rect, root->surface, apos, attribute);
 	} else if (parent == NULL) { // 親がいないなら背景消去の責任をもつ
 		DSurfaceFill(root->surface, apos, 0, 0, 0);
@@ -894,14 +882,6 @@ void PicRoot::ExecUpdate(void) {
 	vector<UpdateItem>::iterator it;
 	vector<UpdateItem>::iterator end = update_rects.end();
 
-if(print_blit){
-	fprintf(stderr,"ExecUpdate Start: \n\t");
-	for (it=update_rects.begin(); it != end; it++) {
-		fprintf(stderr,"(%d,%d,%d,%d), ",it->apos.lx,it->apos.ty,it->apos.rx,it->apos.by);
-	}
-	fprintf(stderr,"\n");
-}
-
 	for (it=update_rects.begin(); it != end; it++) {
 		if (it->rpos.width() == 0) continue;
 
@@ -925,14 +905,6 @@ if(print_blit){
 		}
 	}
 
-if(print_blit){
-	fprintf(stderr,"->\t");
-	for (it=update_rects.begin(); it != end; it++) {
-		fprintf(stderr,"(%d,%d,%d,%d), ",it->apos.lx,it->apos.ty,it->apos.rx,it->apos.by);
-	}
-	fprintf(stderr,"\n");
-}
-
 	int num = update_rects.size();
 	SDL_Rect* r = new SDL_Rect[num];
 	Rect confine = Rect(0, 0, surface->w, surface->h);
@@ -942,10 +914,9 @@ if(print_blit){
 		UpdateItem& item = update_rects[i];
 		Rect& ur = item.apos;
 		if (ur.width() == 0) continue;
-if(print_blit)fprintf(stderr,"%p: %d,%d,%d,%d",item.pic, item.apos.lx, item.apos.ty, item.apos.rx, item.apos.by);
 
 		item.pic->ExecReBlit(item.rpos);
-if(print_blit)fprintf(stderr,"\n");
+
 		ur.intersect(confine);
 		r[n].x = ur.lx;
 		r[n].y = ur.ty;
@@ -954,7 +925,7 @@ if(print_blit)fprintf(stderr,"\n");
 		if (surface != hw_surface) SDL_BlitSurface(surface, &r[n], hw_surface, &r[n]);
 		n++;
 	}
-if(print_blit)fprintf(stderr,"\n");
+
 	SDL_UpdateRects(hw_surface, n, r);
 	delete[] r;
 	update_rects.clear();
@@ -1016,36 +987,36 @@ inline SDL_Rect SDLed(const Rect& rect) 
 #ifndef ALPHA_MAX
 #define ALPHA_MAX 255
 #endif
-void PicRoot::BlitSurface(Surface* src, const Rect& src_r, const unsigned char* alpha, const Rect& alpha_r, Surface* dest, const Rect& dest_r, int attribute) const {
-if (print_blit) fprintf(stderr," s %p %d:%d:%d:%d;",src, dest_r.lx, dest_r.ty, dest_r.rx, dest_r.by);
+void PicRoot::BlitSurface(Surface* src, const Rect& src_r, const unsigned char* alpha, const Rect& alpha_r,
+                          Surface* dest, const Rect& dest_r, int attribute) const
+{
 	SDL_Rect sr = SDLed(src_r); SDL_Rect dr = SDLed(dest_r);
 
-	if (attribute & PicBase::BLIT_MULTIPLY) {
-if (print_blit) fprintf(stderr,"M");
+	if (attribute & PicBase::BLIT_MULTIPLY)
+	{
 		DSurfaceBlitMultiply(src, src_r, dest, dest_r);
 		return;
-	} else if (attribute & PicBase::BLIT_SATURATE && src->format->Amask == 0) {
-if (print_blit) fprintf(stderr,"S");
+	}
+	else if (attribute & PicBase::BLIT_ADD)
+	{
 		unsigned char a = 255;
-		if (alpha && alpha_r.width() >= 1 && alpha_r.height() >= 1) a = *alpha;
-		DSurfaceBlitSaturate(src, src_r, dest, dest_r, a);
+		if (alpha != NULL && alpha_r.width() >= 1 && alpha_r.height() >= 1)
+			a = *alpha;
+		DSurfaceBlitAdd(src, src_r, dest, dest_r, a);
 		return;
 	}
 
-if (print_blit) fprintf(stderr,"N");
-	if (alpha == NULL || alpha_r.width() == 0) { // simple blit
-if (print_blit) fprintf(stderr,"X");
+	if (alpha == NULL || alpha_r.width() == 0) // simple blit
+	{
 		SDL_BlitSurface(src, &sr, dest, &dr);
 		return;
 	}
 	if (alpha_r.width() == 1 && alpha_r.height() == 1) {
 		if (*alpha == 255) {
-if (print_blit) fprintf(stderr,"Y");
 			SDL_BlitSurface(src, &sr, dest, &dr);
 			return;
 		}
 		if (src->format->Amask == 0) { // use per-surface alpha
-if (print_blit) fprintf(stderr,"Z");
 			SDL_SetAlpha(src, SDL_SRCALPHA, *alpha);
 			SDL_BlitSurface(src, &sr, dest, &dr);
 			SDL_SetAlpha(src, 0, 0);
@@ -1053,9 +1024,7 @@ if (print_blit) fprintf(stderr,"Z");
 		}
 	}
 	// generic alpha blit
-if (print_blit) fprintf(stderr,"W");
 	DSurfaceBlitAlpha(src, src_r, dest, dest_r, alpha, alpha_r);
-	return;
 }
 
 bool PicRoot::with_mask(Surface* s) {