1 files changed, 322 insertions, 0 deletions
diff --git a/home/map_objects.asm b/home/map_objects.asm
new file mode 100644
index 00000000..51206cc5
--- /dev/null
+++ b/home/map_objects.asm
@@ -0,0 +1,322 @@
+; checks if the player's coordinates match an arrow movement tile's coordinates
+; and if so, decodes the RLE movement data
+; b = player Y
+; c = player X
+DecodeArrowMovementRLE::
+	ld a, [hli]
+	cp $ff
+	ret z ; no match in the list
+	cp b
+	jr nz, .nextArrowMovementTileEntry1
+	ld a, [hli]
+	cp c
+	jr nz, .nextArrowMovementTileEntry2
+	ld a, [hli]
+	ld d, [hl]
+	ld e, a
+	ld hl, wSimulatedJoypadStatesEnd
+	call DecodeRLEList
+	dec a
+	ld [wSimulatedJoypadStatesIndex], a
+	ret
+.nextArrowMovementTileEntry1
+	inc hl
+.nextArrowMovementTileEntry2
+	inc hl
+	inc hl
+	jr DecodeArrowMovementRLE
+
+TextScript_ItemStoragePC::
+	call SaveScreenTilesToBuffer2
+	ld b, BANK(PlayerPC)
+	ld hl, PlayerPC
+	jr bankswitchAndContinue
+
+TextScript_BillsPC::
+	call SaveScreenTilesToBuffer2
+	ld b, BANK(BillsPC_)
+	ld hl, BillsPC_
+	jr bankswitchAndContinue
+
+TextScript_GameCornerPrizeMenu::
+; XXX find a better name for this function
+; special_F7
+	ld b, BANK(CeladonPrizeMenu)
+	ld hl, CeladonPrizeMenu
+bankswitchAndContinue::
+	call Bankswitch
+	jp HoldTextDisplayOpen        ; continue to main text-engine function
+
+TextScript_PokemonCenterPC::
+	ld b, BANK(ActivatePC)
+	ld hl, ActivatePC
+	jr bankswitchAndContinue
+
+StartSimulatingJoypadStates::
+	xor a
+	ld [wOverrideSimulatedJoypadStatesMask], a
+	ld [wSpritePlayerStateData2MovementByte1], a
+	ld hl, wd730
+	set 7, [hl]
+	ret
+
+IsItemInBag::
+; given an item_id in b
+; set zero flag if item isn't in player's bag
+; else reset zero flag
+; related to Pokémon Tower and ghosts
+	predef GetQuantityOfItemInBag
+	ld a, b
+	and a
+	ret
+
+IsSurfingPikachuInParty::
+; set bit 6 of wd472 if true
+; also calls Func_3467, which is a bankswitch to IsStarterPikachuInOurParty
+	ld a, [wd472]
+	and $3f
+	ld [wd472], a
+	ld hl, wPartyMon1
+	ld c, PARTY_LENGTH
+	ld b, SURF
+.loop
+	ld a, [hl]
+	cp PIKACHU
+	jr nz, .notPikachu
+	push hl
+	ld de, $8
+	add hl, de
+	ld a, [hli]
+	cp b ; does pikachu have surf as one of its moves
+	jr z, .hasSurf
+	ld a, [hli]
+	cp b
+	jr z, .hasSurf
+	ld a, [hli]
+	cp b
+	jr z, .hasSurf
+	ld a, [hli]
+	cp b
+	jr nz, .noSurf
+.hasSurf
+	ld a, [wd472]
+	set 6, a
+	ld [wd472], a
+.noSurf
+	pop hl
+.notPikachu
+	ld de, wPartyMon2 - wPartyMon1
+	add hl, de
+	dec c
+	jr nz, .loop
+	call Func_3467
+	ret
+
+Func_3467::
+	push hl
+	push bc
+	callfar IsStarterPikachuInOurParty
+	pop bc
+	pop hl
+	ret nc
+	ld a, [wd472]
+	set 7, a
+	ld [wd472], a
+	ret
+
+DisplayPokedex::
+	ld [wd11e], a
+	farjp _DisplayPokedex
+
+SetSpriteFacingDirectionAndDelay::
+	call SetSpriteFacingDirection
+	ld c, 6
+	jp DelayFrames
+
+SetSpriteFacingDirection::
+	ld a, SPRITESTATEDATA1_FACINGDIRECTION
+	ldh [hSpriteDataOffset], a
+	call GetPointerWithinSpriteStateData1
+	ldh a, [hSpriteFacingDirection]
+	ld [hl], a
+	ret
+
+SetSpriteImageIndexAfterSettingFacingDirection::
+	ld de, SPRITESTATEDATA1_IMAGEINDEX - SPRITESTATEDATA1_FACINGDIRECTION
+	add hl, de
+	ld [hl], a
+	ret
+
+SpriteFunc_34a1::
+	ldh a, [hSpriteIndex]
+	swap a
+	add $e
+	ld l, a
+	ld h, $c2
+	ld c, [hl]
+	dec c
+	swap c
+	ldh a, [hSpriteOffset]
+	add c
+	ld c, a
+	ldh a, [hSpriteHeight]
+	swap a
+	add $2
+	ld l, a
+	dec h
+	ld [hl], c
+	ret
+
+; tests if the player's coordinates are in a specified array
+; INPUT:
+; hl = address of array
+; OUTPUT:
+; [wCoordIndex] = if there is match, the matching array index
+; sets carry if the coordinates are in the array, clears carry if not
+ArePlayerCoordsInArray::
+	ld a, [wYCoord]
+	ld b, a
+	ld a, [wXCoord]
+	ld c, a
+	; fallthrough
+
+CheckCoords::
+	xor a
+	ld [wCoordIndex], a
+.loop
+	ld a, [hli]
+	cp $ff ; reached terminator?
+	jr z, .notInArray
+	push hl
+	ld hl, wCoordIndex
+	inc [hl]
+	pop hl
+.compareYCoord
+	cp b
+	jr z, .compareXCoord
+	inc hl
+	jr .loop
+.compareXCoord
+	ld a, [hli]
+	cp c
+	jr nz, .loop
+.inArray
+	scf
+	ret
+.notInArray
+	and a
+	ret
+
+; tests if a boulder's coordinates are in a specified array
+; INPUT:
+; hl = address of array
+; [hSpriteIndex] = index of boulder sprite
+; OUTPUT:
+; [wCoordIndex] = if there is match, the matching array index
+; sets carry if the coordinates are in the array, clears carry if not
+CheckBoulderCoords::
+	push hl
+	ld hl, wSpritePlayerStateData2MapY
+	ldh a, [hSpriteIndex]
+	swap a
+	ld d, $0
+	ld e, a
+	add hl, de
+	ld a, [hli]
+	sub $4 ; because sprite coordinates are offset by 4
+	ld b, a
+	ld a, [hl]
+	sub $4 ; because sprite coordinates are offset by 4
+	ld c, a
+	pop hl
+	jp CheckCoords
+
+GetPointerWithinSpriteStateData1::
+	ld h, HIGH(wSpriteStateData1)
+	jr _GetPointerWithinSpriteStateData
+
+GetPointerWithinSpriteStateData2::
+	ld h, HIGH(wSpriteStateData2)
+
+_GetPointerWithinSpriteStateData:
+	ldh a, [hSpriteDataOffset]
+	ld b, a
+	ldh a, [hSpriteIndex]
+	swap a
+	add b
+	ld l, a
+	ret
+
+; decodes a $ff-terminated RLEncoded list
+; each entry is a pair of bytes <byte value> <repetitions>
+; the final $ff will be replicated in the output list and a contains the number of bytes written
+; de: input list
+; hl: output list
+DecodeRLEList::
+	xor a
+	ld [wRLEByteCount], a     ; count written bytes here
+.listLoop
+	ld a, [de]
+	cp $ff
+	jr z, .endOfList
+	ldh [hRLEByteValue], a ; store byte value to be written
+	inc de
+	ld a, [de]
+	ld b, $0
+	ld c, a                      ; number of bytes to be written
+	ld a, [wRLEByteCount]
+	add c
+	ld [wRLEByteCount], a     ; update total number of written bytes
+	ldh a, [hRLEByteValue]
+	call FillMemory              ; write a c-times to output
+	inc de
+	jr .listLoop
+.endOfList
+	ld a, $ff
+	ld [hl], a                   ; write final $ff
+	ld a, [wRLEByteCount]
+	inc a                        ; include sentinel in counting
+	ret
+
+; sets movement byte 1 for sprite [hSpriteIndex] to $FE and byte 2 to [hSpriteMovementByte2]
+SetSpriteMovementBytesToFE::
+	push hl
+	call GetSpriteMovementByte1Pointer
+	ld [hl], $fe
+	call GetSpriteMovementByte2Pointer
+	ldh a, [hSpriteMovementByte2]
+	ld [hl], a
+	pop hl
+	ret
+
+; sets both movement bytes for sprite [hSpriteIndex] to $FF
+SetSpriteMovementBytesToFF::
+	push hl
+	call GetSpriteMovementByte1Pointer
+	ld [hl], $FF
+	call GetSpriteMovementByte2Pointer
+	ld [hl], $FF ; prevent person from walking?
+	pop hl
+	ret
+
+; returns the sprite movement byte 1 pointer for sprite [hSpriteIndex] in hl
+GetSpriteMovementByte1Pointer::
+	ld h, $C2
+	ldh a, [hSpriteIndex]
+	swap a
+	add 6
+	ld l, a
+	ret
+
+; returns the sprite movement byte 2 pointer for sprite [hSpriteIndex] in hl
+GetSpriteMovementByte2Pointer::
+	push de
+	ld hl, wMapSpriteData
+	ldh a, [hSpriteIndex]
+	dec a
+	add a
+	ld e, a
+	ld d, 0
+	add hl, de
+	pop de
+	ret