From 9c8a79d13f324b88afc9eae52372349084a63537 Mon Sep 17 00:00:00 2001
From: Electro <ElectroDeoxys@gmail.com>
Date: Fri, 6 Feb 2026 17:13:31 +0000
Subject: [PATCH] Rename "Bank 20" section to "Load Gfx"

---
 src/engine/gfx/load_gfx.asm     | 310 ++++++++++++++++++++++++++++++++
 src/engine/gfx/load_tilemap.asm | 309 -------------------------------
 src/layout.link                 |   2 +-
 src/main.asm                    |   3 +-
 4 files changed, 312 insertions(+), 312 deletions(-)
 delete mode 100644 src/engine/gfx/load_tilemap.asm

diff --git a/src/engine/gfx/load_gfx.asm b/src/engine/gfx/load_gfx.asm
index 4f026a4..a67acae 100644
--- a/src/engine/gfx/load_gfx.asm
+++ b/src/engine/gfx/load_gfx.asm
@@ -1,3 +1,313 @@
+; loads the BG map corresponding to wCurTilemap to SRAM
+; bc = starting coordinates
+LoadTilemap_ToSRAM:
+	ld a, TRUE
+	ld [wWriteBGMapToSRAM], a
+	jr LoadTilemap
+
+; loads the BG map corresponding to wCurTilemap to VRAM
+; bc = starting coordinates
+LoadTilemap_ToVRAM:
+	xor a ; FALSE
+	ld [wWriteBGMapToSRAM], a
+;	fallthrough
+
+; loads the BG map corresponding to wCurTilemap
+; either loads them in VRAM or SRAM,
+; depending on wWriteBGMapToSRAM
+; bc = starting coordinates
+LoadTilemap:
+	push hl
+	push bc
+	push de
+	call BCCoordToBGMap0Address
+	ld hl, wVRAMPointer
+	ld [hl], e
+	inc hl
+	ld [hl], d
+
+; get pointer and bank for BG Map
+	call Func_803b9
+	ld a, [wTempPointerBank]
+	ld [wBGMapBank], a
+
+; store header data
+	ld de, wDecompressionBuffer
+	ld bc, $6 ; header + 1st instruction
+	call CopyBankedDataToDE
+	ld l, e
+	ld h, d
+	ld a, [hli]
+	ld [wBGMapWidth], a
+	ld a, [hli]
+	ld [wBGMapHeight], a
+	ld a, [hli]
+	ld [wBGMapPermissionDataPtr], a
+	ld a, [hli]
+	ld [wBGMapPermissionDataPtr + 1], a
+	ld a, [hli]
+	ld [wBGMapCGBMode], a
+	call .InitAndDecompressBGMap
+	pop de
+	pop bc
+	pop hl
+	ret
+
+; prepares the pointers for decompressing BG Map
+; and calls InitDataDecompression
+; then decompresses the data
+.InitAndDecompressBGMap
+	push hl
+	push bc
+	push de
+	ld a, [wTempPointer]
+	add $5 ; header
+	ld e, a
+	ld a, [wTempPointer + 1]
+	adc 0
+	ld d, a
+	ld b, HIGH(wDecompressionSecondaryBuffer)
+	call InitDataDecompression
+	ld a, [wVRAMPointer]
+	ld e, a
+	ld a, [wVRAMPointer + 1]
+	ld d, a
+	call .Decompress
+	pop de
+	pop bc
+	pop hl
+	ret
+
+; wTempBank:wTempPointer = source of compressed data
+; wVRAMPointer = destination of decompressed data
+.Decompress
+; if wBGMapCGBMode is true, then use double wBGMapWidth
+; since one "width" length goes to VRAM0
+; and the other "width" length goes to VRAM1
+	push hl
+	ld hl, wDecompressionRowWidth
+	ld a, [wBGMapWidth]
+	ld [hl], a
+	ld a, [wBGMapCGBMode]
+	or a
+	jr z, .skip_doubling_width
+	sla [hl]
+.skip_doubling_width
+
+; clear wDecompressionBuffer
+	ld c, $40
+	ld hl, wDecompressionBuffer
+	xor a
+.loop_clear
+	ld [hli], a
+	dec c
+	jr nz, .loop_clear
+
+; loop each row, up to the number of tiles in height
+	ld a, [wBGMapHeight]
+	ld c, a
+.loop
+	push bc
+	push de
+	ld b, $00
+	ld a, [wDecompressionRowWidth]
+	ld c, a
+	ld de, wDecompressionBuffer
+	call DecompressDataFromBank
+
+	; copy to VRAM0
+	ld a, [wBGMapWidth]
+	ld b, a
+	pop de
+	push de
+	ld hl, wDecompressionBuffer
+	call CopyBGDataToVRAMOrSRAM
+	ld a, [wConsole]
+	cp CONSOLE_CGB
+	jr nz, .next_row
+
+	; cgb only
+	; copy the second "half" to VRAM1
+	call BankswitchVRAM1
+	ld a, [wBGMapWidth]
+	ld c, a
+	ld b, $0
+	ld hl, wDecompressionBuffer
+	add hl, bc
+	pop de
+	push de
+	ld a, [wBGMapWidth]
+	ld b, a
+	call Func_80148 ; adds some wd291 offset to tiles
+	call CopyBGDataToVRAMOrSRAM
+	call BankswitchVRAM0
+
+.next_row
+	pop de
+	ld hl, TILEMAP_WIDTH
+	add hl, de
+	ld e, l
+	ld d, h
+	pop bc
+	dec c
+	jr nz, .loop
+
+	pop hl
+	ret
+
+Func_80148:
+	ld a, [wd291]
+	or a
+	ret z
+	ld a, [wBGMapCGBMode]
+	or a
+	jr z, .asm_80162
+
+; add wd291 to b bytes in hl
+	push hl
+	push bc
+.loop_1
+	push bc
+	ld a, [wd291]
+	add [hl]
+	ld [hli], a
+	pop bc
+	dec b
+	jr nz, .loop_1
+	pop bc
+	pop hl
+	ret
+
+; store wd291 to b bytes in hl
+.asm_80162
+	push hl
+	push bc
+	ld a, [wd291]
+.loop_2
+	ld [hli], a
+	dec b
+	jr nz, .loop_2
+	pop bc
+	pop hl
+	ret
+
+; copies BG Map data pointed by hl
+; to either VRAM or SRAM, depending on wWriteBGMapToSRAM
+; de is the target address in VRAM,
+; if SRAM is the target address to copy,
+; copies data to sGfxBuffer0 or sGfxBuffer1
+; for VRAM0 or VRAM1 respectively
+CopyBGDataToVRAMOrSRAM:
+	ld a, [wWriteBGMapToSRAM]
+	or a
+	jp z, SafeCopyDataHLtoDE
+
+; copies b bytes from hl to SRAM1
+	push hl
+	push bc
+	push de
+	ldh a, [hBankSRAM]
+	push af
+	ld a, BANK("SRAM1")
+	call BankswitchSRAM
+	push hl
+	ld hl, sGfxBuffer0 - v0BGMap0
+	ldh a, [hBankVRAM]
+	or a
+	jr z, .got_pointer
+	ld hl, sGfxBuffer1 - v1BGMap0
+.got_pointer
+	add hl, de
+	ld e, l
+	ld d, h
+	pop hl
+.loop
+	ld a, [hli]
+	ld [de], a
+	inc de
+	dec b
+	jr nz, .loop
+	pop af
+	call BankswitchSRAM
+	call DisableSRAM
+	pop de
+	pop bc
+	pop hl
+	ret
+
+; safely copies $20 bytes at a time
+; sGfxBuffer0 -> v0BGMap0
+; sGfxBuffer1 -> v0BGMap1 (if in CGB)
+SafelyCopyBGMapFromSRAMToVRAM:
+	push hl
+	push bc
+	push de
+	ldh a, [hBankSRAM]
+	push af
+	ld a, BANK("SRAM1")
+	call BankswitchSRAM
+	ld hl, sGfxBuffer0
+	ld de, v0BGMap0
+	ld c, $20
+.loop
+	push bc
+	push hl
+	push de
+	ld b, $20
+	call SafeCopyDataHLtoDE
+	ld a, [wConsole]
+	cp CONSOLE_CGB
+	jr nz, .skip_vram1
+	pop de
+	pop hl
+	push hl
+	push de
+	ld bc, sGfxBuffer1 - sGfxBuffer0 ; $400
+	add hl, bc
+	call BankswitchVRAM1
+	ld b, $20
+	call SafeCopyDataHLtoDE
+	call BankswitchVRAM0
+.skip_vram1
+
+	pop hl
+	ld de, $20
+	add hl, de
+	ld e, l
+	ld d, h
+	pop hl
+	ld bc, $20
+	add hl, bc
+	pop bc
+	dec c
+	jr nz, .loop
+	pop af
+	call BankswitchSRAM
+	call DisableSRAM
+	pop de
+	pop bc
+	pop hl
+	ret
+
+; clears sGfxBuffer0 and sGfxBuffer1
+ClearSRAMBGMaps:
+	push hl
+	push bc
+	ldh a, [hBankSRAM]
+	push af
+	ld a, BANK(sGfxBuffer0) ; SRAM 1
+	call BankswitchSRAM
+	ld hl, sGfxBuffer0
+	ld bc, $800 ; sGfxBuffer0 + sGfxBuffer1
+	xor a
+	call FillMemoryWithA
+	pop af
+	call BankswitchSRAM
+	call DisableSRAM
+	pop bc
+	pop hl
+	ret
+
 ; l - GFXTABLE_* constant (banks 0,1,2,3,4)
 ; a - map index (inside of the given bank)
 GetMapDataPointer:
diff --git a/src/engine/gfx/load_tilemap.asm b/src/engine/gfx/load_tilemap.asm
deleted file mode 100644
index b96b8c5..0000000
--- a/src/engine/gfx/load_tilemap.asm
+++ /dev/null
@@ -1,309 +0,0 @@
-; loads the BG map corresponding to wCurTilemap to SRAM
-; bc = starting coordinates
-LoadTilemap_ToSRAM:
-	ld a, TRUE
-	ld [wWriteBGMapToSRAM], a
-	jr LoadTilemap
-
-; loads the BG map corresponding to wCurTilemap to VRAM
-; bc = starting coordinates
-LoadTilemap_ToVRAM:
-	xor a ; FALSE
-	ld [wWriteBGMapToSRAM], a
-;	fallthrough
-
-; loads the BG map corresponding to wCurTilemap
-; either loads them in VRAM or SRAM,
-; depending on wWriteBGMapToSRAM
-; bc = starting coordinates
-LoadTilemap:
-	push hl
-	push bc
-	push de
-	call BCCoordToBGMap0Address
-	ld hl, wVRAMPointer
-	ld [hl], e
-	inc hl
-	ld [hl], d
-
-; get pointer and bank for BG Map
-	call Func_803b9
-	ld a, [wTempPointerBank]
-	ld [wBGMapBank], a
-
-; store header data
-	ld de, wDecompressionBuffer
-	ld bc, $6 ; header + 1st instruction
-	call CopyBankedDataToDE
-	ld l, e
-	ld h, d
-	ld a, [hli]
-	ld [wBGMapWidth], a
-	ld a, [hli]
-	ld [wBGMapHeight], a
-	ld a, [hli]
-	ld [wBGMapPermissionDataPtr], a
-	ld a, [hli]
-	ld [wBGMapPermissionDataPtr + 1], a
-	ld a, [hli]
-	ld [wBGMapCGBMode], a
-	call .InitAndDecompressBGMap
-	pop de
-	pop bc
-	pop hl
-	ret
-
-; prepares the pointers for decompressing BG Map
-; and calls InitDataDecompression
-; then decompresses the data
-.InitAndDecompressBGMap
-	push hl
-	push bc
-	push de
-	ld a, [wTempPointer]
-	add $5 ; header
-	ld e, a
-	ld a, [wTempPointer + 1]
-	adc 0
-	ld d, a
-	ld b, HIGH(wDecompressionSecondaryBuffer)
-	call InitDataDecompression
-	ld a, [wVRAMPointer]
-	ld e, a
-	ld a, [wVRAMPointer + 1]
-	ld d, a
-	call .Decompress
-	pop de
-	pop bc
-	pop hl
-	ret
-
-; wTempBank:wTempPointer = source of compressed data
-; wVRAMPointer = destination of decompressed data
-.Decompress
-; if wBGMapCGBMode is true, then use double wBGMapWidth
-; since one "width" length goes to VRAM0
-; and the other "width" length goes to VRAM1
-	push hl
-	ld hl, wDecompressionRowWidth
-	ld a, [wBGMapWidth]
-	ld [hl], a
-	ld a, [wBGMapCGBMode]
-	or a
-	jr z, .skip_doubling_width
-	sla [hl]
-.skip_doubling_width
-
-; clear wDecompressionBuffer
-	ld c, $40
-	ld hl, wDecompressionBuffer
-	xor a
-.loop_clear
-	ld [hli], a
-	dec c
-	jr nz, .loop_clear
-
-; loop each row, up to the number of tiles in height
-	ld a, [wBGMapHeight]
-	ld c, a
-.loop
-	push bc
-	push de
-	ld b, $00
-	ld a, [wDecompressionRowWidth]
-	ld c, a
-	ld de, wDecompressionBuffer
-	call DecompressDataFromBank
-
-	; copy to VRAM0
-	ld a, [wBGMapWidth]
-	ld b, a
-	pop de
-	push de
-	ld hl, wDecompressionBuffer
-	call CopyBGDataToVRAMOrSRAM
-	ld a, [wConsole]
-	cp CONSOLE_CGB
-	jr nz, .next_row
-
-	; cgb only
-	; copy the second "half" to VRAM1
-	call BankswitchVRAM1
-	ld a, [wBGMapWidth]
-	ld c, a
-	ld b, $0
-	ld hl, wDecompressionBuffer
-	add hl, bc
-	pop de
-	push de
-	ld a, [wBGMapWidth]
-	ld b, a
-	call Func_80148 ; adds some wd291 offset to tiles
-	call CopyBGDataToVRAMOrSRAM
-	call BankswitchVRAM0
-
-.next_row
-	pop de
-	ld hl, TILEMAP_WIDTH
-	add hl, de
-	ld e, l
-	ld d, h
-	pop bc
-	dec c
-	jr nz, .loop
-
-	pop hl
-	ret
-
-Func_80148:
-	ld a, [wd291]
-	or a
-	ret z
-	ld a, [wBGMapCGBMode]
-	or a
-	jr z, .asm_80162
-
-; add wd291 to b bytes in hl
-	push hl
-	push bc
-.loop_1
-	push bc
-	ld a, [wd291]
-	add [hl]
-	ld [hli], a
-	pop bc
-	dec b
-	jr nz, .loop_1
-	pop bc
-	pop hl
-	ret
-
-; store wd291 to b bytes in hl
-.asm_80162
-	push hl
-	push bc
-	ld a, [wd291]
-.loop_2
-	ld [hli], a
-	dec b
-	jr nz, .loop_2
-	pop bc
-	pop hl
-	ret
-
-; copies BG Map data pointed by hl
-; to either VRAM or SRAM, depending on wWriteBGMapToSRAM
-; de is the target address in VRAM,
-; if SRAM is the target address to copy,
-; copies data to sGfxBuffer0 or sGfxBuffer1
-; for VRAM0 or VRAM1 respectively
-CopyBGDataToVRAMOrSRAM:
-	ld a, [wWriteBGMapToSRAM]
-	or a
-	jp z, SafeCopyDataHLtoDE
-
-; copies b bytes from hl to SRAM1
-	push hl
-	push bc
-	push de
-	ldh a, [hBankSRAM]
-	push af
-	ld a, BANK("SRAM1")
-	call BankswitchSRAM
-	push hl
-	ld hl, sGfxBuffer0 - v0BGMap0
-	ldh a, [hBankVRAM]
-	or a
-	jr z, .got_pointer
-	ld hl, sGfxBuffer1 - v1BGMap0
-.got_pointer
-	add hl, de
-	ld e, l
-	ld d, h
-	pop hl
-.loop
-	ld a, [hli]
-	ld [de], a
-	inc de
-	dec b
-	jr nz, .loop
-	pop af
-	call BankswitchSRAM
-	call DisableSRAM
-	pop de
-	pop bc
-	pop hl
-	ret
-
-; safely copies $20 bytes at a time
-; sGfxBuffer0 -> v0BGMap0
-; sGfxBuffer1 -> v0BGMap1 (if in CGB)
-SafelyCopyBGMapFromSRAMToVRAM:
-	push hl
-	push bc
-	push de
-	ldh a, [hBankSRAM]
-	push af
-	ld a, BANK("SRAM1")
-	call BankswitchSRAM
-	ld hl, sGfxBuffer0
-	ld de, v0BGMap0
-	ld c, $20
-.loop
-	push bc
-	push hl
-	push de
-	ld b, $20
-	call SafeCopyDataHLtoDE
-	ld a, [wConsole]
-	cp CONSOLE_CGB
-	jr nz, .skip_vram1
-	pop de
-	pop hl
-	push hl
-	push de
-	ld bc, sGfxBuffer1 - sGfxBuffer0 ; $400
-	add hl, bc
-	call BankswitchVRAM1
-	ld b, $20
-	call SafeCopyDataHLtoDE
-	call BankswitchVRAM0
-.skip_vram1
-
-	pop hl
-	ld de, $20
-	add hl, de
-	ld e, l
-	ld d, h
-	pop hl
-	ld bc, $20
-	add hl, bc
-	pop bc
-	dec c
-	jr nz, .loop
-	pop af
-	call BankswitchSRAM
-	call DisableSRAM
-	pop de
-	pop bc
-	pop hl
-	ret
-
-; clears sGfxBuffer0 and sGfxBuffer1
-ClearSRAMBGMaps:
-	push hl
-	push bc
-	ldh a, [hBankSRAM]
-	push af
-	ld a, BANK(sGfxBuffer0) ; SRAM 1
-	call BankswitchSRAM
-	ld hl, sGfxBuffer0
-	ld bc, $800 ; sGfxBuffer0 + sGfxBuffer1
-	xor a
-	call FillMemoryWithA
-	pop af
-	call BankswitchSRAM
-	call DisableSRAM
-	pop bc
-	pop hl
-	ret
diff --git a/src/layout.link b/src/layout.link
index 7f5e451..07c661d 100644
--- a/src/layout.link
+++ b/src/layout.link
@@ -114,7 +114,7 @@ ROMX $1d
 ROMX $1e
 	"Gfx 2"
 ROMX $20
-	"Bank 20"
+	"Load Gfx"
 	"Gfx"
 ROMX $21
 	"Gfx 3"
diff --git a/src/main.asm b/src/main.asm
index 0199fa8..244814b 100644
--- a/src/main.asm
+++ b/src/main.asm
@@ -171,9 +171,8 @@ INCLUDE "data/cards.asm"
 SECTION "SGB", ROMX
 INCLUDE "engine/sgb.asm"
 
-SECTION "Bank 20", ROMX
+SECTION "Load Gfx", ROMX
 INCLUDE "engine/overworld/load_overworld.asm"
-INCLUDE "engine/gfx/load_tilemap.asm"
 INCLUDE "engine/gfx/load_gfx.asm"
 INCLUDE "engine/overworld/animation.asm"
 INCLUDE "engine/overworld/map_events.asm"