[Decompilation] [th01] HUD: Inter-page row-sized rectangle blitting

Both inlined and non-inlined page switching within the same function,
together with an approach that doesn't correspond to our other planar
access macros? That code must have been written during a very
experimental phase very early in the development of this game.

Part of P0104, funded by Ember2528.

planar.h

@@ -76,6 +76,11 @@ static inline unsigned int vram_offset_muldiv(int x, int y)
 {
 	return (y * ROW_SIZE) + (x / 8);
 }
+
+static inline unsigned int vram_offset_divmul(int x, int y)
+{
+	return (x / 8) + (y * ROW_SIZE);
+}
 #endif
 
 #define VRAM_CHUNK(plane, offset, bit_count) \

th01/main/hud/hud.cpp

@@ -18,7 +18,11 @@ static const int CUR_FX = FX(7, 3, 0);
 #if (PTN_QUARTER_W < GLYPH_FULL_W)
 	#error Original code assumes PTN_QUARTER_W >= GLYPH_FULL_W
 #endif
+#if (PTN_QUARTER_H < GLYPH_H)
+	#error Original code assumes PTN_QUARTER_H >= GLYPH_H
+#endif
 static const int COL_W = PTN_QUARTER_W;
+static const int ROW_H = PTN_QUARTER_H;
 
 static const int SCORE_W = (SCORE_DIGITS * COL_W);
 
@@ -235,21 +239,8 @@ void score_and_cardcombo_put_initial(bool16 first_run)
 	}
 	cardcombo_put_initial(MAX_TOP, MAX_FX);
 
-	/* TODO: Replace with the decompiled calls
-	 * 	graph_copy_hud_row_0_to_1_8(SCORE_LEFT, MAX_TOP, SCORE_AND_CARDCOMBO_W);
-	 * 	graph_copy_hud_row_0_to_1_8(SCORE_LEFT, CUR_TOP, SCORE_AND_CARDCOMBO_W);
-	 * once that function is part of this translation unit */
-	#define call(top) __asm { \
-		db  	0x66, 0x68, top, 0x00, SCORE_AND_CARDCOMBO_W, 0x00; \
-		push	SCORE_LEFT; \
-		nop; \
-		push	cs; \
-		call	near ptr graph_copy_hud_row_0_to_1_8; \
-		add 	sp, 6; \
-	}
-	call(MAX_TOP);
-	call(CUR_TOP);
-
+	graph_copy_hud_row_0_to_1_8(SCORE_LEFT, MAX_TOP, SCORE_AND_CARDCOMBO_W);
+	graph_copy_hud_row_0_to_1_8(SCORE_LEFT, CUR_TOP, SCORE_AND_CARDCOMBO_W);
 	hud_cardcombo_max = 0;
 }
 
@@ -312,3 +303,30 @@ int hud_bg_load(const char *fn)
 	return 0;
 }
 /// ----------
+
+void graph_copy_hud_row_0_to_1_8(int left, int top, int w)
+{
+	uint16_t vram_offset;
+	dots16_t dots;
+	int y;
+	uint16_t vram_offset_row = vram_offset_divmul(left, top);
+	int x;
+
+	vram_offset = vram_offset_row;
+	for(y = 0; y < ROW_H; y++) {
+		vram_offset = vram_offset_row;
+		for(x = 0; x < (w / 16); x++) {
+			#define copy_plane(plane) \
+				OUTW(0xA6, 0);	VRAM_SNAP(dots, plane, vram_offset, 16); \
+				OUTW(0xA6, 1);	VRAM_PUT(plane, vram_offset, dots, 16);
+			copy_plane(B);
+			copy_plane(R);
+			copy_plane(G);
+			copy_plane(E);
+			vram_offset += sizeof(dots);
+			#undef copy_plane
+		}
+		vram_offset_row += ROW_SIZE;
+	}
+	graph_accesspage_func(0);
+}

th01_reiiden.asm

@@ -14356,116 +14356,14 @@ main_25_TEXT	segment	byte public 'CODE' use16
 	extern _score_and_cardcombo_put_initial:proc
 	extern _hud_bg_put:proc
 	extern _hud_bg_load:proc
+	extern _graph_copy_hud_row_0_to_1_8:proc
 main_25_TEXT	ends
 
 main_25__TEXT	segment	byte public 'CODE' use16
 		assume cs:main_25
 		;org 9
 		assume es:nothing, ss:nothing, ds:_DATA, fs:nothing, gs:nothing
 
-; =============== S U B	R O U T	I N E =======================================
-
-; Attributes: bp-based frame
-public _graph_copy_hud_row_0_to_1_8
-_graph_copy_hud_row_0_to_1_8	proc far
-
-var_6		= word ptr -6
-var_4		= word ptr -4
-var_2		= word ptr -2
-arg_0		= word ptr  6
-arg_2		= word ptr  8
-arg_4		= word ptr  0Ah
-
-		enter	6, 0
-		push	si
-		push	di
-		mov	ax, [bp+arg_0]
-		mov	bx, 8
-		cwd
-		idiv	bx
-		mov	dx, [bp+arg_2]
-		imul	dx, 50h
-		add	ax, dx
-		mov	[bp+var_4], ax
-		mov	si, [bp+var_4]
-		mov	[bp+var_2], 0
-		jmp	loc_18D84
-; ---------------------------------------------------------------------------
-
-loc_18CF8:
-		mov	si, [bp+var_4]
-		mov	[bp+var_6], 0
-		jmp	short loc_18D6F
-; ---------------------------------------------------------------------------
-
-loc_18D02:
-		mov	dx, 0A6h
-		xor	ax, ax
-		out	dx, ax
-		les	bx, _VRAM_PLANE_B
-		add	bx, si
-		mov	di, es:[bx]
-		mov	ax, 1
-		out	dx, ax
-		mov	bx, word ptr _VRAM_PLANE_B
-		add	bx, si
-		mov	es:[bx], di
-		xor	ax, ax
-		out	dx, ax
-		les	bx, _VRAM_PLANE_R
-		add	bx, si
-		mov	di, es:[bx]
-		mov	ax, 1
-		out	dx, ax
-		mov	bx, word ptr _VRAM_PLANE_R
-		add	bx, si
-		mov	es:[bx], di
-		xor	ax, ax
-		out	dx, ax
-		les	bx, _VRAM_PLANE_G
-		add	bx, si
-		mov	di, es:[bx]
-		mov	ax, 1
-		out	dx, ax
-		mov	bx, word ptr _VRAM_PLANE_G
-		add	bx, si
-		mov	es:[bx], di
-		xor	ax, ax
-		out	dx, ax
-		les	bx, _VRAM_PLANE_E
-		add	bx, si
-		mov	di, es:[bx]
-		mov	ax, 1
-		out	dx, ax
-		mov	bx, word ptr _VRAM_PLANE_E
-		add	bx, si
-		mov	es:[bx], di
-		add	si, 2
-		inc	[bp+var_6]
-
-loc_18D6F:
-		mov	ax, [bp+arg_4]
-		mov	bx, 16
-		cwd
-		idiv	bx
-		cmp	ax, [bp+var_6]
-		jg	short loc_18D02
-		add	[bp+var_4], ROW_SIZE
-		inc	[bp+var_2]
-
-loc_18D84:
-		cmp	[bp+var_2], GLYPH_H
-		jl	loc_18CF8
-		push	0
-		call	_graph_accesspage_func
-		pop	cx
-		pop	di
-		pop	si
-		leave
-		retf
-_graph_copy_hud_row_0_to_1_8	endp
-
-
 ; =============== S U B	R O U T	I N E =======================================
 
 ; Attributes: bp-based frame