Use constants for VBlank handlers

constants/wram_constants.asm

@@ -324,3 +324,16 @@ DEF DAYCARELADY_ACTIVE_F         EQU 7
 	const UNLOCKED_UNOWNS_S_TO_W_F
 	const UNLOCKED_UNOWNS_X_TO_Z_F
 DEF NUM_UNLOCKED_UNOWN_SETS EQU const_value
+
+; hVBlank::
+; VBlankHandlers indexes (see home/vblank.asm)
+	const_def
+	const VBLANK_NORMAL       ; 0
+	const VBLANK_CUTSCENE     ; 1
+	const VBLANK_SOUND_ONLY   ; 2
+	const VBLANK_CUTSCENE_CGB ; 3
+	const VBLANK_SERIAL       ; 4
+	const VBLANK_CREDITS      ; 5
+	const VBLANK_DMA_TRANSFER ; 6
+	const VBLANK_UNUSED       ; 7
+DEF NUM_VBLANK_HANDLERS EQU const_value

docs/bugs_and_glitches.md

@@ -1556,7 +1556,7 @@ To select a move in battle, you have to press and release the Up or Down buttons
 -; BUG: Credits sequence changes move selection menu behavior (see docs/bugs_and_glitches.md)
  	ldh a, [hVBlank]
  	push af
- 	ld a, $5
+ 	ld a, VBLANK_CREDITS
  	ldh [hVBlank], a
 +	ldh a, [hInMenu]
 +	push af

engine/battle/battle_transition.asm

@@ -22,7 +22,7 @@ DoBattleTransition:
 	ld a, [hl]
 	push af
 	vc_hook Reduce_battle_transition_flashing
-	ld [hl], $1
+	ld [hl], VBLANK_CUTSCENE
 
 .loop
 	ld a, [wJumptableIndex]

engine/battle_anims/anim_commands.asm

@@ -24,11 +24,11 @@ _PlayBattleAnim:
 	call BattleAnimRequestPals
 	call BattleAnimDelayFrame
 
-	ld c, 1
+	ld c, VBLANK_CUTSCENE
 	ldh a, [rKEY1]
 	bit 7, a ; check CGB double speed mode
 	jr nz, .got_speed
-	ld c, 3
+	ld c, VBLANK_CUTSCENE_CGB
 
 .got_speed
 	ld hl, hVBlank

engine/events/magnet_train.asm

@@ -38,7 +38,7 @@ MagnetTrain:
 	ld hl, hVBlank
 	ld a, [hl]
 	push af
-	ld [hl], 1
+	ld [hl], VBLANK_CUTSCENE
 .loop
 	ld a, [wJumptableIndex]
 	and a

engine/link/link.asm

@@ -537,6 +537,7 @@ LinkTimeout:
 	xor a
 	ld [hld], a
 	ld [hl], a
+	assert VBLANK_NORMAL == 0
 	ldh [hVBlank], a
 	push de
 	hlcoord 0, 12
@@ -2380,7 +2381,7 @@ CheckLinkTimeout_Receptionist:
 	xor a
 	ld [hl], a
 	call WaitBGMap
-	ld a, $2
+	ld a, VBLANK_SOUND_ONLY
 	ldh [hVBlank], a
 	call DelayFrame
 	call DelayFrame
@@ -2402,7 +2403,7 @@ CheckLinkTimeout_Gen2:
 	xor a
 	ld [hl], a
 	call WaitBGMap
-	ld a, $2
+	ld a, VBLANK_SOUND_ONLY
 	ldh [hVBlank], a
 	call DelayFrame
 	call DelayFrame
@@ -2630,7 +2631,7 @@ Link_EnsureSync:
 	add $d0
 	ld [wLinkPlayerSyncBuffer], a
 	ld [wLinkPlayerSyncBuffer + 1], a
-	ld a, $2
+	ld a, VBLANK_SOUND_ONLY
 	ldh [hVBlank], a
 	call DelayFrame
 	call DelayFrame

engine/movie/credits.asm

@@ -76,7 +76,7 @@ Credits::
 ; BUG: Credits sequence changes move selection menu behavior (see docs/bugs_and_glitches.md)
 	ldh a, [hVBlank]
 	push af
-	ld a, $5
+	ld a, VBLANK_CREDITS
 	ldh [hVBlank], a
 	ld a, TRUE
 	ldh [hInMenu], a

engine/movie/intro.asm

@@ -45,9 +45,10 @@ CrystalIntro:
 	ret
 
 .InitRAMAddrs:
+	assert VBLANK_NORMAL == 0
 	xor a
 	ldh [hVBlank], a
-	ld a, $1
+	ld a, TRUE
 	ldh [hInMenu], a
 	xor a
 	ldh [hMapAnims], a

engine/printer/printer.asm

@@ -71,7 +71,7 @@ PrintDexEntry:
 	ld hl, hVBlank
 	ld a, [hl]
 	push af
-	ld [hl], 4 ; vblank mode that calls AskSerial
+	ld [hl], VBLANK_SERIAL
 
 	ld a, 8 ; 16 rows
 	ld [wPrinterQueueLength], a
@@ -146,7 +146,7 @@ PrintPCBox:
 	ld hl, hVBlank
 	ld a, [hl]
 	push af
-	ld [hl], 4 ; vblank mode that calls AskSerial
+	ld [hl], VBLANK_SERIAL
 
 	xor a
 	ldh [hBGMapMode], a
@@ -227,7 +227,7 @@ PrintUnownStamp:
 	ld hl, hVBlank
 	ld a, [hl]
 	push af
-	ld [hl], 4 ; vblank mode that calls AskSerial
+	ld [hl], VBLANK_SERIAL
 
 	xor a
 	ldh [hBGMapMode], a
@@ -302,7 +302,7 @@ PrintMail:
 	ld hl, hVBlank
 	ld a, [hl]
 	push af
-	ld [hl], 4 ; vblank mode that calls AskSerial
+	ld [hl], VBLANK_SERIAL
 
 	ld a, 18 / 2
 	ld [wPrinterQueueLength], a
@@ -345,7 +345,7 @@ PrintPartymon:
 	ld hl, hVBlank
 	ld a, [hl]
 	push af
-	ld [hl], 4 ; vblank mode that calls AskSerial
+	ld [hl], VBLANK_SERIAL
 
 	ld a, 16 / 2
 	ld [wPrinterQueueLength], a
@@ -403,7 +403,7 @@ _PrintDiploma:
 	ld hl, hVBlank
 	ld a, [hl]
 	push af
-	ld [hl], 4 ; vblank mode that calls AskSerial
+	ld [hl], VBLANK_SERIAL
 
 	ln a, 1, 0 ; to be loaded to wPrinterMargins
 	call Printer_PrepareTilemapForPrint

home/vblank.asm

@@ -13,11 +13,11 @@ VBlank::
 	push hl
 
 	ldh a, [hVBlank]
-	and 7
+	maskbits NUM_VBLANK_HANDLERS
 
 	ld e, a
 	ld d, 0
-	ld hl, .VBlanks
+	ld hl, VBlankHandlers
 	add hl, de
 	add hl, de
 	ld a, [hli]
@@ -34,17 +34,20 @@ VBlank::
 	pop af
 	reti
 
-.VBlanks:
-	dw VBlank0
-	dw VBlank1
-	dw VBlank2
-	dw VBlank3
-	dw VBlank4
-	dw VBlank5
-	dw VBlank6
-	dw VBlank0 ; just in case
-
-VBlank0::
+VBlankHandlers:
+; entries correspond to VBLANK_* constants (see constants/wram_constants.asm)
+	table_width 2, VBlankHandlers
+	dw VBlank_Normal
+	dw VBlank_Cutscene
+	dw VBlank_SoundOnly
+	dw VBlank_CutsceneCGB
+	dw VBlank_Serial
+	dw VBlank_Credits
+	dw VBlank_DMATransfer
+	dw VBlank_Normal ; unused
+	assert_table_length NUM_VBLANK_HANDLERS
+
+VBlank_Normal::
 ; normal operation
 
 ; rng
@@ -144,7 +147,7 @@ VBlank0::
 
 	ret
 
-VBlank2::
+VBlank_SoundOnly::
 ; sound only
 
 	ldh a, [hROMBank]
@@ -161,7 +164,7 @@ VBlank2::
 	ld [wVBlankOccurred], a
 	ret
 
-VBlank1::
+VBlank_Cutscene::
 ; scx, scy
 ; palettes
 ; bg map
@@ -245,7 +248,7 @@ UpdatePals::
 	and a
 	ret
 
-VBlank3::
+VBlank_CutsceneCGB::
 ; scx, scy
 ; palettes
 ; bg map
@@ -309,7 +312,7 @@ VBlank3::
 	ldh [rIF], a
 	ret
 
-VBlank4::
+VBlank_Serial::
 ; bg map
 ; tiles
 ; oam
@@ -340,13 +343,12 @@ VBlank4::
 	rst Bankswitch
 	ret
 
-VBlank5::
+VBlank_Credits::
 ; scx
 ; palettes
 ; bg map
 ; tiles
 ; joypad
-;
 
 	ldh a, [hROMBank]
 	ldh [hROMBankBackup], a
@@ -388,7 +390,7 @@ VBlank5::
 	ldh [rIE], a
 	ret
 
-VBlank6::
+VBlank_DMATransfer::
 ; palettes
 ; tiles
 ; dma transfer

mobile/mobile_40.asm

@@ -94,6 +94,7 @@ DisableMobile:
 	xor a
 	ldh [hMobileReceive], a
 	ldh [hMobile], a
+	assert VBLANK_NORMAL == 0
 	xor a
 	ldh [hVBlank], a
 	call NormalSpeed
@@ -1378,7 +1379,7 @@ Function1008e0:
 	push bc
 	xor a
 	ldh [hBGMapMode], a
-	ld a, $03
+	ld a, VBLANK_CUTSCENE_CGB
 	ldh [hVBlank], a
 	call Function100970
 	call Function100902