Decipher and label the $1c duel-gfx block (Gfx2)

The bank switch in CopyFontsOrDuelGraphicsTiles is done by BankpushROM
(src/home/switch_rom.asm): it sets bank = BANK(Fonts) + the top 2 bits of
hl and masks the address into $4000-$7fff. So an operand hl<$4000 reads
Gfx1 (bank $1b) at hl+$4000, while $4000<=hl<$8000 reads Gfx2 (bank $1c)
at hl. A SameBoy trace confirmed this (header/symbol loaders read $1b;
the draw-cards/box-message loaders read $1c).

With that, the formerly anonymous $1c:4000-4a30 blob (gfx_070000.bin) is
fully identified -- 163 tiles partition exactly into 7 duel-screen
graphics, each carved out as a labeled region and INCBIN'd:

  $4000 (36t) DuelCheckPokemonScreenGfx     face-down cards + ACT/BPx
  $4240 (45t) DuelPlayAreaScreenGfx         play-area screen (CGB)
  $4510 (45t) DuelPlayAreaScreenGfxDMG      play-area screen (DMG/SGB)
  $47e0 (13t) DuelDeckAndDiscardPileIcons
  $48b0  (8t) DuelCoinTossResultTiles       [O]/[X]
  $4930  (8t) DuelMenuAndCardPicBorderTiles
  $49b0  (8t) DuelDrawCardsScreenIcons      Deck/Hand

The raw $4xxx operands in tiles.asm/bills_pc.asm now reference these
labels (byte-faithful: each label resolves to the old constant), and
Func_1dff -> LoadDuelPlayAreaScreenTiles since it loads that region.

make compare: poketcg2.gbc OK (byte-identical).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/engine/bank02.asm

@@ -543,7 +543,7 @@ _DrawYourOrOppPlayAreaScreen::
 
 DrawYourOrOppPlayAreaScreen_EmptiedScreen:
 	call LoadSymbolsFont
-	call Func_1dff
+	call LoadDuelPlayAreaScreenTiles
 	bank1call SetDefaultPalettes
 	lb de, 6, 0
 	call InitTextPrinting
@@ -637,7 +637,7 @@ DrawInPlayAreaScreen::
 	push af
 	ld a, CONSOLE_DMG
 	ld [wConsole], a
-	call Func_1dff
+	call LoadDuelPlayAreaScreenTiles
 	pop af
 	ld [wConsole], a
 	bank1call SetDefaultPalettes
@@ -694,7 +694,7 @@ _DrawPlayersPrizeAndBenchCards::
 	call DoFrame
 	call EmptyScreen
 	call LoadSymbolsFont
-	call Func_1dff
+	call LoadDuelPlayAreaScreenTiles
 ; player cards
 	ld a, PLAYER_TURN
 	ld [wCheckMenuPlayAreaWhichDuelist], a

src/engine/bills_pc.asm

@@ -76,7 +76,7 @@ _BillsPC:
 	call SetupText
 
 	call EmptyScreen
-	ld hl, $4930 ; DuelOtherGraphics + $30 tiles
+	ld hl, DuelMenuAndCardPicBorderTiles
 	ld de, v0Tiles2 + $30 tiles
 	ld b, 8
 	call CopyFontsOrDuelGraphicsTiles

src/gfx/card_graphics.asm

@@ -19,7 +19,20 @@ DuelOtherGraphics::
 	INCBIN "gfx/duel/duel_other_gfx.bin"
 
 SECTION "Gfx 1c", ROMX[$4000], BANK[$1c]
-	INCBIN "gfx/cards/misc/gfx_070000.bin"
+DuelCheckPokemonScreenGfx::
+	INCBIN "gfx/duel/check_pokemon_screen.bin"
+DuelPlayAreaScreenGfx::
+	INCBIN "gfx/duel/play_area_screen.bin"
+DuelPlayAreaScreenGfxDMG::
+	INCBIN "gfx/duel/play_area_screen_dmg.bin"
+DuelDeckAndDiscardPileIcons::
+	INCBIN "gfx/duel/deck_discard_icons.bin"
+DuelCoinTossResultTiles::
+	INCBIN "gfx/duel/coin_toss_result_symbols.bin"
+DuelMenuAndCardPicBorderTiles::
+	INCBIN "gfx/duel/menu_card_pic_border.bin"
+DuelDrawCardsScreenIcons::
+	INCBIN "gfx/duel/draw_cards_icons.bin"
 DuelBoxMessages::
 	INCBIN "gfx/duel/box_messages.2bpp"
 	ds $2450, $ff

src/home/tiles.asm

@@ -64,7 +64,7 @@ LoadCardSet2Tiles::
 	add hl, hl
 	add hl, hl
 	add hl, hl
-	ld de, $3dd0 ; DuelOtherGraphics + $1d tiles
+	ld de, DuelOtherGraphics + $1d tiles - $4000 ; card set 2 icons
 	add hl, de
 	ld de, v0Tiles1 + $7c tiles
 	ld b, $04
@@ -86,7 +86,7 @@ LoadCardSet2Tiles::
 
 ; loads the Deck and Hand icons for the "Draw X card(s) from the deck." screen
 LoadDuelDrawCardsScreenTiles::
-	ld hl, $49b0 ; DuelOtherGraphics + $29 tiles
+	ld hl, DuelDrawCardsScreenIcons
 	ld de, v0Tiles1 + $74 tiles
 	ld b, $08
 	jp CopyFontsOrDuelGraphicsTiles
@@ -102,7 +102,7 @@ LoadDuelCheckPokemonScreenTiles::
 ;	fallthrough
 
 .got_num_tiles
-	ld hl, $4000
+	ld hl, DuelCheckPokemonScreenGfx
 	ld de, v0Tiles1 + $50 tiles
 	call CopyFontsOrDuelGraphicsTiles
 	bank1call Func_6c12
@@ -111,7 +111,7 @@ LoadDuelCheckPokemonScreenTiles::
 ; loads the 8 tiles that make up the border of the main duel menu as well as the border
 ; of a large card picture (displayed after drawing the card or placing it in the arena).
 LoadCardOrDuelMenuBorderTiles::
-	ld hl, $4930 ; DuelOtherGraphics + $15 tiles
+	ld hl, DuelMenuAndCardPicBorderTiles
 	ld de, v0Tiles1 + $50 tiles
 	ld b, $08
 	jr CopyFontsOrDuelGraphicsTiles
@@ -150,16 +150,18 @@ LoadDeckAndDiscardPileIcons::
 	ld de, $cb16
 	ld c, $08
 	call CopyFontsOrDuelGraphicsBytes
-	ld hl, $47e0
+	ld hl, DuelDeckAndDiscardPileIcons
 	ld de, $8a00
 	ld b, $0d
 	call CopyFontsOrDuelGraphicsTiles
-Func_1dff::
-	ld hl, $4240
+; load the tiles for the player's / opponent's Play Area screen
+; (uses a separate set of tiles on CGB vs DMG/SGB)
+LoadDuelPlayAreaScreenTiles::
+	ld hl, DuelPlayAreaScreenGfx
 	ld a, [wConsole]
 	cp CONSOLE_CGB
 	jr z, .copy
-	ld hl, $4510
+	ld hl, DuelPlayAreaScreenGfxDMG
 .copy
 	ld de, v0Tiles1 + $50 tiles
 	ld b, $30
@@ -171,7 +173,7 @@ LoadDuelCoinTossResultTiles::
 	ld de, $cafe
 	ld c, $08
 	call CopyFontsOrDuelGraphicsBytes
-	ld hl, $48b0 ; DuelOtherGraphics + $d tiles
+	ld hl, DuelCoinTossResultTiles
 	ld de, v0Tiles2 + $30 tiles
 	ld b, $08
 	jr CopyFontsOrDuelGraphicsTiles
@@ -203,7 +205,7 @@ Func_212f::
 	ld b, $30
 	call CopyFontsOrDuelGraphicsTiles
 ; text box frame tiles
-	ld hl, $4930 ; DuelOtherGraphics + $15 tiles
+	ld hl, DuelMenuAndCardPicBorderTiles
 	ld de, sGfxBuffer1 + $30 tiles
 	ld b, $8
 	call CopyFontsOrDuelGraphicsTiles

tools/extract_card_gfx.py

@@ -37,12 +37,26 @@ REGION_END   = 0xd9818  # end of last card; rest of region is 0xff pad
 # tiles = 48+48+19+64). The loaders keep their raw operands; these labels just
 # document and source the data.
 #   (file offset, size, label, gfx path stem, png width in tiles | None for raw .bin)
+# Bank-layout note: these duel graphics are reached through CopyFontsOrDuelGraphicsTiles,
+# whose BankpushROM (src/home/switch_rom.asm) sets bank = BANK(Fonts) + hl's top 2 bits and
+# masks the address into $4000-$7fff. So an operand hl<$4000 reads Gfx1 (bank $1b) at hl+$4000,
+# while $4000<=hl<$8000 reads Gfx2 (bank $1c) at hl. That's why the $1b tail (file 0x6f4d0..0x70000)
+# and the $1c block (file 0x70000..) are one logical duel-gfx region split across two banks.
 KNOWN_PRE = [
+    # --- Gfx1 tail (bank $1b), referenced as `<label> - $4000` -------------------------------
     (0x6f4d0, 48*16,   'DuelCardHeaderGraphics',   'gfx/duel/card_type_headers',    None),  # TRAINER/ENERGY/POKEMON
     (0x6f7d0, 48*16,   'DuelCgbSymbolGraphics',    'gfx/duel/cgb_card_symbols',     None),  # CGB rarity/type symbols
     (0x6fad0, 19*16,   'DuelDmgSgbSymbolGraphics', 'gfx/duel/dmg_sgb_card_symbols', None),  # DMG/SGB symbols
-    (0x6fc00, 64*16,   'DuelOtherGraphics',        'gfx/duel/duel_other_gfx',       None),
-    (0x70a30, 7*40*16, 'DuelBoxMessages',          'gfx/duel/box_messages',         10),    # 7 box msgs, 10x4
+    (0x6fc00, 64*16,   'DuelOtherGraphics',        'gfx/duel/duel_other_gfx',       None),  # incl. card set 2 icons (LoadCardSet2Tiles)
+    # --- Gfx2 ($1c:4000..4a30), referenced by the raw $4xxx operands directly ----------------
+    (0x70000, 36*16,   'DuelCheckPokemonScreenGfx',     'gfx/duel/check_pokemon_screen', None),  # face-down cards + ACT/BPx (LoadDuelCheckPokemonScreenTiles)
+    (0x70240, 45*16,   'DuelPlayAreaScreenGfx',         'gfx/duel/play_area_screen',     None),  # CGB play-area screen (Func_1dff)
+    (0x70510, 45*16,   'DuelPlayAreaScreenGfxDMG',      'gfx/duel/play_area_screen_dmg', None),  # DMG/SGB variant
+    (0x707e0, 13*16,   'DuelDeckAndDiscardPileIcons',   'gfx/duel/deck_discard_icons',   None),  # LoadDeckAndDiscardPileIcons
+    (0x708b0,  8*16,   'DuelCoinTossResultTiles',       'gfx/duel/coin_toss_result_symbols', None),  # [O]/[X] (LoadDuelCoinTossResultTiles); distinct from CoinTossResultGfx
+    (0x70930,  8*16,   'DuelMenuAndCardPicBorderTiles', 'gfx/duel/menu_card_pic_border', None),  # LoadCardOrDuelMenuBorderTiles
+    (0x709b0,  8*16,   'DuelDrawCardsScreenIcons',      'gfx/duel/draw_cards_icons',     None),  # Deck/Hand (LoadDuelDrawCardsScreenTiles)
+    (0x70a30, 7*40*16, 'DuelBoxMessages',               'gfx/duel/box_messages',         10),    # 7 box msgs, 10x4
 ]
 ROOT = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
 GFXDIR = os.path.join(ROOT, "src/gfx/cards")

tools/trace_gfx_reads.py

@@ -56,10 +56,18 @@ def classify(bank, addr):
             if lo <= addr < hi:
                 return off, f"{name} + ${addr-lo:x} ($1b:{addr:04x})"
     if bank == 0x1c:
-        if 0x4000 <= addr < 0x4a30:
-            return off, f"$1c:4000-4a30 UNLABELED blob (gfx_070000) + ${addr-0x4000:x}"
-        if 0x4a30 <= addr < 0x5bb0:
-            return off, f"DuelBoxMessages + ${addr-0x4a30:x} ($1c:{addr:04x})"
+        for lo, hi, name in [
+            (0x4000, 0x4240, "DuelCheckPokemonScreenGfx"),
+            (0x4240, 0x4510, "DuelPlayAreaScreenGfx"),
+            (0x4510, 0x47e0, "DuelPlayAreaScreenGfxDMG"),
+            (0x47e0, 0x48b0, "DuelDeckAndDiscardPileIcons"),
+            (0x48b0, 0x4930, "DuelCoinTossResultTiles"),
+            (0x4930, 0x49b0, "DuelMenuAndCardPicBorderTiles"),
+            (0x49b0, 0x4a30, "DuelDrawCardsScreenIcons"),
+            (0x4a30, 0x5bb0, "DuelBoxMessages"),
+        ]:
+            if lo <= addr < hi:
+                return off, f"{name} + ${addr-lo:x} ($1c:{addr:04x})"
         return off, f"$1c:{addr:04x} (padding region)"
     if 0x1d <= bank <= 0x36:
         idx = (off - CG) // 8