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|
UpdateBGMapBuffer:: ; 1458 (0:1458)
ld a, [hBGMapUpdate]
and a
ret z
ld [hSPBuffer], sp
ld hl, wBGMapBufferPtrs
ld sp, hl
ld hl, wBGMapPalBuffer
ld de, wBGMapBuffer
.next
rept 2
pop bc
ld a, $1
ld [rVBK], a
ld a, [hli]
ld [bc], a
inc c
ld a, [hli]
ld [bc], a
dec c
ld a, $0
ld [rVBK], a
ld a, [de]
inc de
ld [bc], a
inc c
ld a, [de]
inc de
ld [bc], a
endr
ld a, [hFFDE]
dec a
dec a
ld [hFFDE], a
jr nz, .next
ld a, [hSPBuffer]
ld l, a
ld a, [hSPBuffer + 1]
ld h, a
ld sp, hl
xor a
ld [hBGMapUpdate], a
scf
ret
WaitTop::
ld a, [hBGMapMode]
and a
ret z
ld a, [hBGMapThird]
and a
jr z, .done
call DelayFrame
jr WaitTop
.done
xor a
ld [hBGMapMode], a
ret
UpdateBGMap:: ; 14bb (0:14bb)
ld a, [hBGMapMode]
and a
ret z
dec a
jr z, .Tiles
dec a
jr z, .Attr
dec a
ld a, [hBGMapAddress]
ld l, a
ld a, [hBGMapAddress + 1]
ld h, a
push hl
xor a
ld [hBGMapAddress], a
ld a, $9c
ld [hBGMapAddress + 1], a
ld a, [hBGMapMode]
push af
cp $3
call z, .Tiles
pop af
cp $4
call z, .Attr
pop hl
ld a, l
ld [hBGMapAddress], a
ld a, h
ld [hBGMapAddress + 1], a
ret
.Attr
ld a, $1
ld [rVBK], a
hlcoord 0, 0, wAttrMap
call .update
ld a, $0
ld [rVBK], a
ret
.Tiles
hlcoord 0, 0
.update
ld [hSPBuffer], sp
ld a, [hBGMapThird]
and a
jr z, .top
dec a
jr z, .middle
THIRD_HEIGHT EQU SCREEN_HEIGHT / 3
ld de, 2 * THIRD_HEIGHT * SCREEN_WIDTH
add hl, de
ld sp, hl
ld a, [hBGMapAddress + 1]
ld h, a
ld a, [hBGMapAddress]
ld l, a
ld de, 2 * THIRD_HEIGHT * BG_MAP_WIDTH
add hl, de
xor a
jr .start
.middle
ld de, THIRD_HEIGHT * SCREEN_WIDTH
add hl, de
ld sp, hl
ld a, [hBGMapAddress + 1]
ld h, a
ld a, [hBGMapAddress]
ld l, a
ld de, THIRD_HEIGHT * BG_MAP_WIDTH
add hl, de
ld a, $2
jr .start
.top
ld sp, hl
ld a, [hBGMapAddress + 1]
ld h, a
ld a, [hBGMapAddress]
ld l, a
ld a, $1
.start
ld [hBGMapThird], a
ld a, SCREEN_HEIGHT / 3
; Discrepancy between TileMap and BGMap
ld bc, BG_MAP_WIDTH - (SCREEN_WIDTH - 1)
.row
rept SCREEN_WIDTH / 2 - 1
pop de
ld [hl], e
inc l
ld [hl], d
inc l
endr
pop de
ld [hl], e
inc l
ld [hl], d
add hl, bc
dec a
jr nz, .row
ld a, [hSPBuffer]
ld l, a
ld a, [hSPBuffer + 1]
ld h, a
ld sp, hl
ret
Serve1bppRequest:: ; 1579 (0:1579)
ld a, [wRequested1bpp]
and a
ret z
ld [hSPBuffer], sp
ld hl, wRequested1bppSource
ld a, [hli]
ld h, [hl]
ld l, a
ld sp, hl
ld hl, wRequested1bppDest
ld a, [hli]
ld h, [hl]
ld l, a
ld a, [wRequested1bpp]
ld b, a
xor a
ld [wRequested1bpp], a
.next
rept 3
pop de
ld [hl], e
inc l
ld [hl], e
inc l
ld [hl], d
inc l
ld [hl], d
inc l
endr
pop de
ld [hl], e
inc l
ld [hl], e
inc l
ld [hl], d
inc l
ld [hl], d
inc hl
dec b
jr nz, .next
ld a, l
ld [wRequested1bppDest], a
ld a, h
ld [wRequested1bppDest + 1], a
ld [wRequested1bppSource], sp
ld a, [hSPBuffer]
ld l, a
ld a, [hSPBuffer + 1]
ld h, a
ld sp, hl
ret
Serve2bppRequest:: ; 15d0 (0:15d0)
ld a, [wRequested2bpp]
and a
ret z
ld [hSPBuffer], sp
ld hl, wRequested2bppSource
ld a, [hli]
ld h, [hl]
ld l, a
ld sp, hl
ld hl, wRequested2bppDest
ld a, [hli]
ld h, [hl]
ld l, a
ld a, [wRequested2bpp]
ld b, a
xor a
ld [wRequested2bpp], a
.next
rept 7
pop de
ld [hl], e
inc l
ld [hl], d
inc l
endr
pop de
ld [hl], e
inc l
ld [hl], d
inc hl
dec b
jr nz, .next
ld a, l
ld [wRequested2bppDest], a
ld a, h
ld [wRequested2bppDest + 1], a
ld [wRequested2bppSource], sp
ld a, [hSPBuffer]
ld l, a
ld a, [hSPBuffer + 1]
ld h, a
ld sp, hl
ret
AnimateTileset:: ; 162b (0:162b)
ld a, [hMapAnims]
and a
ret z
ld a, [hROMBank]
push af
ld a, $3f
rst Bankswitch
call $4003
pop af
rst Bankswitch
ret
ret
ld hl, rLCDC
set 1, [hl]
ret
Function1642:: ; 1642 (0:1642)
nop
ld a, [hFF9E]
and a
ret z
dec a
jr z, .one
dec a
jr z, .two
ld a, $2
ld [hFF9E], a
ld hl, hBGMapAddress
ld a, [hli]
ld h, [hl]
ld l, a
ld de, SCREEN_WIDTH
add hl, de
ld b, $12
ld a, $60
.loop1
rept 12
ld [hli], a
endr
add hl, de
dec b
jr nz, .loop1
ret
.two
ld a, $1
ld de, $240
jr .go
.one
xor a
ld de, $320
.go
ld [hFF9E], a
ld hl, hBGMapAddress
ld a, [hli]
ld h, [hl]
ld l, a
add hl, de
ld b, $e
ld a, $60
.loop2
rept 16
ld [hli], a
endr
dec b
jr nz, .loop2
ret
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