underwater tileset shit, brings number of errors down to 20

it's currently missing the custom palette but if I did I'd need to fuck with the code for it anyway when I add it properly when this stuff works so I dont think that's a big deal

constants/tileset_constants.asm

@@ -53,6 +53,7 @@
 	const TILESET_NIHON_WHITECITY	   ; 33
 	const TILESET_SEVII				   ; 34
 	const TILESET_LUSHCAVE			   ; 35
+	const TILESET_UNDERWATER		   ; 36
 DEF NUM_TILESETS EQU const_value - 1
 
 ; wTileset struct size

data/tilesets.asm

@@ -65,4 +65,5 @@ Tilesets::
 	tileset TilesetNihonWhiteCity
 	tileset TilesetSevii
 	tileset TilesetLushCave
+	tileset TilesetUnderwater
 	assert_table_length NUM_TILESETS + 1

engine/tilesets/tileset_palettes.asm

@@ -228,3 +228,26 @@ LoadDesertPalette:
 	ret
 	
 INCLUDE "gfx/tilesets/desert.pal"
+
+
+LoadSpecialMapObjectPalette:
+	ld a, [wMapTileset]
+	cp TILESET_UNDERWATER
+	jr z, .underwater
+	jr .do_nothing
+.underwater
+	call LoadUnderwaterObjectPalette
+	scf
+	ret
+.do_nothing
+	and a
+	ret
+LoadUnderwaterObjectPalette:
+	ld a, BANK(wOBPals1)
+	ld de, wOBPals1
+	ld hl, UnderwaterObjectPalette
+	ld bc, 8 palettes
+	call FarCopyWRAM
+	ret
+UnderwaterObjectPalette:
+INCLUDE "gfx/tilesets/underwater_sprites.pal"

gfx/tilesets.asm

@@ -668,3 +668,15 @@ INCBIN "data/tilesets/players_room_metatiles.bin"
 
 TilesetPlayersRoomColl::
 INCLUDE "data/tilesets/players_room_collision.asm"
+
+TilesetUnderwaterGFX::
+INCBIN "gfx/tilesets/underwater.2bpp.lz"
+
+TilesetUnderwaterMeta::
+INCBIN "data/tilesets/underwater_metatiles.bin"
+
+TilesetUnderwaterColl::
+INCLUDE "data/tilesets/underwater_collision.asm"
+
+TilesetUnderwaterAttr::
+INCBIN "data/tilesets/underwater_attributes.bin"

gfx/tilesets/underwater_sprites.pal

@@ -0,0 +1,40 @@
+; red
+	RGB 14, 17, 24
+	RGB 11, 19, 10
+	RGB 11, 07, 01
+	RGB 00, 00, 00
+; blue
+	RGB 14, 17, 24
+	RGB 11, 19, 10
+	RGB 10, 09, 29
+	RGB 00, 00, 00
+; green
+	RGB 14, 17, 24
+	RGB 11, 19, 10
+	RGB 07, 22, 03
+	RGB 00, 00, 00
+; brown
+	RGB 14, 17, 24
+	RGB 11, 19, 10
+	RGB 11, 10, 03
+	RGB 00, 00, 00
+; pink
+	RGB 14, 17, 24
+	RGB 11, 19, 10
+	RGB 10, 09, 02
+	RGB 00, 00, 00
+; silver
+	RGB 31, 31, 31
+	RGB 31, 31, 31
+	RGB 13, 13, 13
+	RGB 00, 00, 00
+; tree (bg green)
+	RGB 19, 31, 19
+	RGB 11, 21, 28
+	RGB 04, 16, 24
+	RGB 00, 00, 00
+; rock (bg brown)
+	RGB 14, 17, 24
+	RGB 08, 09, 16
+	RGB 04, 05, 10
+	RGB 02, 02, 04