pokecrystal-board/engine/phone/phonering_copytilemapatonce.asm
Rangi eb1e3636bb Use labels instead of constants for HRAM
Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld
2018-08-25 14:28:22 -04:00

81 lines
1.1 KiB
NASM

PhoneRing_CopyTilemapAtOnce:
ldh a, [hCGB]
and a
jp z, WaitBGMap
ld a, [wSpriteUpdatesEnabled]
cp $0
jp z, WaitBGMap
; What follows is a modified version of CopyTilemapAtOnce.
ldh a, [hBGMapMode]
push af
xor a
ldh [hBGMapMode], a
ldh a, [hMapAnims]
push af
xor a
ldh [hMapAnims], a
.wait
ldh a, [rLY]
cp LY_VBLANK - 1
jr c, .wait
di
ld a, BANK(vBGMap2)
ldh [rVBK], a
hlcoord 0, 0, wAttrMap
call .CopyTilemapAtOnce
ld a, BANK(vBGMap0)
ldh [rVBK], a
hlcoord 0, 0
call .CopyTilemapAtOnce
.wait2
ldh a, [rLY]
cp LY_VBLANK - 1
jr c, .wait2
ei
pop af
ldh [hMapAnims], a
pop af
ldh [hBGMapMode], a
ret
.CopyTilemapAtOnce:
ld [hSPBuffer], sp
ld sp, hl
ldh a, [hBGMapAddress + 1]
ld h, a
ld l, 0
ld a, SCREEN_HEIGHT
ldh [hTilesPerCycle], a
ld b, 1 << 1 ; not in v/hblank
ld c, LOW(rSTAT)
.loop
rept SCREEN_WIDTH / 2
pop de
.loop\@
ld a, [$ff00+c]
and b
jr nz, .loop\@
ld [hl], e
inc l
ld [hl], d
inc l
endr
ld de, BG_MAP_WIDTH - SCREEN_WIDTH
add hl, de
ldh a, [hTilesPerCycle]
dec a
ldh [hTilesPerCycle], a
jr nz, .loop
ldh a, [hSPBuffer]
ld l, a
ldh a, [hSPBuffer + 1]
ld h, a
ld sp, hl
ret