From 80cec5b2318da7a36a863138f9834d28d4401bd1 Mon Sep 17 00:00:00 2001
From: nmlgc <nmlgc@nmlgc.net>
Date: Sat, 28 Dec 2019 21:20:48 +0100
Subject: [PATCH] [Reverse-engineering] [th03] 1P/2P selection gaiji cursor

Part of P0064, funded by Touhou Patch Center.
---
 pc98.h                          |  3 +-
 pc98.inc                        |  3 +-
 th03/gaiji/gaiji.h              | 16 +++++++++
 th03/gaiji/gaiji.inc            | 19 ++++++++++
 th03/strings/p_cursor[data].asm |  7 ++++
 th03/th03.inc                   |  1 +
 th03_op.asm                     | 61 ++++++++++++++-------------------
 7 files changed, 72 insertions(+), 38 deletions(-)
 create mode 100644 th03/gaiji/gaiji.h
 create mode 100644 th03/gaiji/gaiji.inc
 create mode 100644 th03/strings/p_cursor[data].asm

diff --git a/pc98.h b/pc98.h
index 1ddfa940..a82049a0 100644
--- a/pc98.h
+++ b/pc98.h
@@ -4,7 +4,8 @@
 
 /// Text
 /// ----
-#define GAIJI_TRAM_W 2
+#define GAIJI_W 16
+#define GAIJI_TRAM_W (GAIJI_W / 8)
 #define GLYPH_HEIGHT 16
 /// ----
 
diff --git a/pc98.inc b/pc98.inc
index baf29f8f..b1eee647 100644
--- a/pc98.inc
+++ b/pc98.inc
@@ -4,7 +4,8 @@
 
 ; Text
 ; ====
-GAIJI_TRAM_W = 2
+GAIJI_W = 16
+GAIJI_TRAM_W = (GAIJI_W / 8)
 GLYPH_HEIGHT = 16
 ; ====
 
diff --git a/th03/gaiji/gaiji.h b/th03/gaiji/gaiji.h
new file mode 100644
index 00000000..55e8ba31
--- /dev/null
+++ b/th03/gaiji/gaiji.h
@@ -0,0 +1,16 @@
+// ReC98
+// -----
+// Gaiji available to TH03
+
+// 1P/2P selection cursor
+#define gc_GAIJI_W 2
+typedef enum {
+	gc_P1_TOP_1 = 0x12,
+	gc_P1_TOP_2 = 0x13,
+	gc_P1_BOTTOM_1 = 0x14,
+	gc_P1_BOTTOM_2 = 0x15,
+	gc_P2_TOP_1 = 0x16,
+	gc_P2_TOP_2 = 0x17,
+	gc_P2_BOTTOM_1 = 0x18,
+	gc_P2_BOTTOM_2 = 0x19,
+} gaiji_cursor_t;
diff --git a/th03/gaiji/gaiji.inc b/th03/gaiji/gaiji.inc
new file mode 100644
index 00000000..b6e2c1de
--- /dev/null
+++ b/th03/gaiji/gaiji.inc
@@ -0,0 +1,19 @@
+; ReC98
+; -----
+; Gaiji available to TH03
+
+; 1P/2P selection cursor
+; ----------------------
+gc_GAIJI_W = 2
+
+gc_P1_TOP_1 = 012h
+gc_P1_TOP_2 = 013h
+gc_P1_BOTTOM_1 = 014h
+gc_P1_BOTTOM_2 = 015h
+gc_P2_TOP_1 = 016h
+gc_P2_TOP_2 = 017h
+gc_P2_BOTTOM_1 = 018h
+gc_P2_BOTTOM_2 = 019h
+; ----------------------
+
+include th03/gaiji/bar.inc
diff --git a/th03/strings/p_cursor[data].asm b/th03/strings/p_cursor[data].asm
new file mode 100644
index 00000000..be01e020
--- /dev/null
+++ b/th03/strings/p_cursor[data].asm
@@ -0,0 +1,7 @@
+public _P_CURSOR_TOP, _P_CURSOR_BOTTOM
+_P_CURSOR_TOP label byte
+	db  gc_P1_TOP_1, gc_P1_TOP_2, 0
+	db  gc_P2_TOP_1, gc_P2_TOP_2, 0
+_P_CURSOR_BOTTOM label byte
+	db  gc_P1_BOTTOM_1, gc_P1_BOTTOM_2, 0
+	db  gc_P2_BOTTOM_1, gc_P2_BOTTOM_2, 0
diff --git a/th03/th03.inc b/th03/th03.inc
index 46e1d6a6..d1b1c594 100644
--- a/th03/th03.inc
+++ b/th03/th03.inc
@@ -1,6 +1,7 @@
 GAME = 3
 include defconv.inc
 include th03/mem.inc
+include th03/gaiji/gaiji.inc
 include th03/math/randring.inc
 include th03/hardware/input.inc
 include th03/chars/chars.inc
diff --git a/th03_op.asm b/th03_op.asm
index 20fc2624..18f289b3 100644
--- a/th03_op.asm
+++ b/th03_op.asm
@@ -3183,11 +3183,11 @@ sub_B747	endp
 ; =============== S U B	R O U T	I N E =======================================
 
 ; Attributes: bp-based frame
+public P_CURSOR_PUT
+p_cursor_put	proc near
 
-sub_B8A6	proc near
-
-var_2		= word ptr -2
-arg_0		= byte ptr  4
+@@y		= word ptr -2
+@@col		= byte ptr  4
 arg_2		= word ptr  6
 
 		enter	2, 0
@@ -3197,36 +3197,36 @@ arg_2		= word ptr  6
 		mov	ax, si
 		shl	ax, 4
 		shl	ax, 3
-		add	ax, 0F0h
+		add	ax, 240
 		mov	di, ax
 		mov	al, [si+2468h]
 		cbw
-		imul	ax, 14h
-		add	ax, 80h
-		mov	[bp+var_2], ax
+		imul	ax, 20
+		add	ax, 128
+		mov	[bp+@@y], ax
 		push	di
 		push	ax
-		push	10h
+		push	GAIJI_W
 		push	ds
 		mov	ax, si
-		imul	ax, 3
-		add	ax, 0A4Dh
+		imul	ax, (gc_GAIJI_W + 1)
+		add	ax, offset _P_CURSOR_TOP
 		push	ax
-		mov	al, [bp+arg_0]
+		mov	al, [bp+@@col]
 		mov	ah, 0
 		push	ax
 		call	graph_gaiji_puts
 		push	di
-		mov	ax, [bp+var_2]
-		add	ax, 10h
+		mov	ax, [bp+@@y]
+		add	ax, GLYPH_HEIGHT
 		push	ax
-		push	10h
+		push	GAIJI_W
 		push	ds
 		mov	ax, si
-		imul	ax, 3
-		add	ax, 0A53h
+		imul	ax, (gc_GAIJI_W + 1)
+		add	ax, offset _P_CURSOR_BOTTOM
 		push	ax
-		mov	al, [bp+arg_0]
+		mov	al, [bp+@@col]
 		mov	ah, 0
 		push	ax
 		call	graph_gaiji_puts
@@ -3234,7 +3234,7 @@ arg_2		= word ptr  6
 		pop	si
 		leave
 		retn	4
-sub_B8A6	endp
+p_cursor_put	endp
 
 
 ; =============== S U B	R O U T	I N E =======================================
@@ -3474,7 +3474,7 @@ loc_BB22:
 
 loc_BB24:
 		push	ax
-		call	sub_B8A6
+		call	p_cursor_put
 		push	1
 		cmp	byte_FC5B, 0
 		jz	short loc_BB35
@@ -3487,7 +3487,7 @@ loc_BB35:
 
 loc_BB37:
 		push	ax
-		call	sub_B8A6
+		call	p_cursor_put
 		call	_input_reset_sense_key_held
 		call	_input_mode
 		push	_input_mp_p1
@@ -3615,7 +3615,7 @@ loc_BC8E:
 
 loc_BC90:
 		push	ax
-		call	sub_B8A6
+		call	p_cursor_put
 		cmp	byte_FC5A, 0
 		jz	short loc_BCAE
 		push	1
@@ -3630,7 +3630,7 @@ loc_BCA8:
 
 loc_BCAA:
 		push	ax
-		call	sub_B8A6
+		call	p_cursor_put
 
 loc_BCAE:
 		push	_input_sp
@@ -3748,7 +3748,7 @@ loc_BDDD:
 
 loc_BDDF:
 		push	ax
-		call	sub_B8A6
+		call	p_cursor_put
 		call	_input_reset_sense_key_held
 		call	_input_mode
 		push	_input_sp
@@ -4108,18 +4108,7 @@ off_E1FE	dd a00sl_cd2
 		db    5
 		db    5
 		db    3
-		db  12h
-		db  13h
-		db    0
-		db  16h
-		db  17h
-		db    0
-		db  14h
-		db  15h
-		db    0
-		db  18h
-		db  19h
-		db    0
+include th03/strings/p_cursor[data].asm
 		db    0
 		db    0
 a00sl_cd2	db '00SL.CD2',0