ReanchorBGMap_NoOAMUpdate::
	call DelayFrame
	ldh a, [hOAMUpdate]
	push af

	ld a, $1
	ldh [hOAMUpdate], a
	ldh a, [hBGMapMode]
	push af
	xor a
	ldh [hBGMapMode], a

	call .ReanchorBGMap

	pop af
	ldh [hBGMapMode], a
	pop af
	ldh [hOAMUpdate], a

	ld hl, wVramState
	set 6, [hl]
	ret

.ReanchorBGMap:
	xor a
	ldh [hLCDCPointer], a
	ldh [hBGMapMode], a
	; prepare vBGMap1/vBGMap3 to be displayed while vBGMap0/vBGMap2 is reanchored.
	; draw screen at wTilemap and wAttrmap and then transfer it.
	ld a, $90
	ldh [hWY], a
	call LoadScreenTilemapAndAttrmapPals
	call LoadWindowHUD
	ld a, HIGH(vBGMap1)
	call .LoadBGMapAddrIntoHRAM
	call HDMATransferTilemapAndAttrmap_OpenAndCloseMenu
	farcall ApplyPals
	ld a, TRUE
	ldh [hCGBPalUpdate], a
	; display window using vBGMap1/vBGMap3 while vBGMap0/vBGMap2 is reanchored.
	; disable LCD interrupt to prevent cropping the window if window HUD is active
	; (caller must re-enable when window is hidden again).
	xor a
	ldh [rSTAT], a
	ldh [hBGMapMode], a
	ldh [hWY], a
	farcall HDMATransfer_FillBGMap0WithBlack ; no need to farcall
	ld a, HIGH(vBGMap0)
	call .LoadBGMapAddrIntoHRAM
	xor a ; LOW(vBGMap0)
	ld [wBGMapAnchor], a
	ld a, HIGH(vBGMap0)
	ld [wBGMapAnchor + 1], a
	xor a
	ldh [hSCX], a
	ldh [hSCY], a
	call ApplyBGMapAnchorToObjects
	ret

.LoadBGMapAddrIntoHRAM:
	ldh [hBGMapAddress + 1], a
	xor a
	ldh [hBGMapAddress], a
	ret

LoadFont_NoOAMUpdate::
	ldh a, [hOAMUpdate]
	push af
	ld a, $1
	ldh [hOAMUpdate], a

	call LoadFrame
	call HideWindow_EnableLCDInt
	call SafeUpdateSprites
	call LoadStandardFont

	pop af
	ldh [hOAMUpdate], a
	ret

LoadOverworldFont_NoOAMUpdate::
	ldh a, [hOAMUpdate]
	push af
	ld a, $1
	ldh [hOAMUpdate], a

	call LoadOverworldFontAndFrame
	ld a, $90
	ldh [hWY], a
	call SafeUpdateSprites

	pop af
	ldh [hOAMUpdate], a
	ret

HDMATransfer_FillBGMap0WithBlack:
	ldh a, [rSVBK]
	push af
	ld a, BANK(wDecompressScratch)
	ldh [rSVBK], a

	ld a, "■"
	ld hl, wDecompressScratch
	ld bc, wScratchAttrmap - wDecompressScratch
	call ByteFill
	ld a, HIGH(wDecompressScratch)
	ldh [rHDMA1], a
	ld a, LOW(wDecompressScratch)
	ldh [rHDMA2], a
	ld a, HIGH(vBGMap0 - VRAM_Begin)
	ldh [rHDMA3], a
	ld a, LOW(vBGMap0 - VRAM_Begin)
	ldh [rHDMA4], a
	ld a, $3f
	ldh [hDMATransfer], a
	call DelayFrame

	pop af
	ldh [rSVBK], a
	ret