1 files changed, 228 insertions, 0 deletions
diff --git a/home/copy2.asm b/home/copy2.asm
new file mode 100644
index 00000000..f7e0a9da
--- /dev/null
+++ b/home/copy2.asm
@@ -0,0 +1,228 @@
+FarCopyData2::
+; Identical to FarCopyData, but uses $ff8b
+; as temp space instead of wBuffer.
+	ld [$ff8b],a
+	ld a,[H_LOADEDROMBANK]
+	push af
+	ld a,[$ff8b]
+	ld [H_LOADEDROMBANK],a
+	ld [MBC3RomBank],a
+	call CopyData
+	pop af
+	ld [H_LOADEDROMBANK],a
+	ld [MBC3RomBank],a
+	ret
+
+FarCopyData3::
+; Copy bc bytes from a:de to hl.
+	ld [$ff8b],a
+	ld a,[H_LOADEDROMBANK]
+	push af
+	ld a,[$ff8b]
+	ld [H_LOADEDROMBANK],a
+	ld [MBC3RomBank],a
+	push hl
+	push de
+	push de
+	ld d,h
+	ld e,l
+	pop hl
+	call CopyData
+	pop de
+	pop hl
+	pop af
+	ld [H_LOADEDROMBANK],a
+	ld [MBC3RomBank],a
+	ret
+
+FarCopyDataDouble::
+; Expand bc bytes of 1bpp image data
+; from a:hl to 2bpp data at de.
+	ld [$ff8b],a
+	ld a,[H_LOADEDROMBANK]
+	push af
+	ld a,[$ff8b]
+	ld [H_LOADEDROMBANK],a
+	ld [MBC3RomBank],a
+.loop
+	ld a,[hli]
+	ld [de],a
+	inc de
+	ld [de],a
+	inc de
+	dec bc
+	ld a,c
+	or b
+	jr nz,.loop
+	pop af
+	ld [H_LOADEDROMBANK],a
+	ld [MBC3RomBank],a
+	ret
+
+CopyVideoData::
+; Wait for the next VBlank, then copy c 2bpp
+; tiles from b:de to hl, 8 tiles at a time.
+; This takes c/8 frames.
+
+	ld a, [H_AUTOBGTRANSFERENABLED]
+	push af
+	xor a ; disable auto-transfer while copying
+	ld [H_AUTOBGTRANSFERENABLED], a
+
+	ld a, [H_LOADEDROMBANK]
+	ld [$ff8b], a
+
+	ld a, b
+	ld [H_LOADEDROMBANK], a
+	ld [MBC3RomBank], a
+
+	ld a, e
+	ld [H_VBCOPYSRC], a
+	ld a, d
+	ld [H_VBCOPYSRC + 1], a
+
+	ld a, l
+	ld [H_VBCOPYDEST], a
+	ld a, h
+	ld [H_VBCOPYDEST + 1], a
+
+.loop
+	ld a, c
+	cp 8
+	jr nc, .keepgoing
+
+.done
+	ld [H_VBCOPYSIZE], a
+	call DelayFrame
+	ld a, [$ff8b]
+	ld [H_LOADEDROMBANK], a
+	ld [MBC3RomBank], a
+	pop af
+	ld [H_AUTOBGTRANSFERENABLED], a
+	ret
+
+.keepgoing
+	ld a, 8
+	ld [H_VBCOPYSIZE], a
+	call DelayFrame
+	ld a, c
+	sub 8
+	ld c, a
+	jr .loop
+
+CopyVideoDataDouble::
+; Wait for the next VBlank, then copy c 1bpp
+; tiles from b:de to hl, 8 tiles at a time.
+; This takes c/8 frames.
+	ld a, [H_AUTOBGTRANSFERENABLED]
+	push af
+	xor a ; disable auto-transfer while copying
+	ld [H_AUTOBGTRANSFERENABLED], a
+	ld a, [H_LOADEDROMBANK]
+	ld [$ff8b], a
+
+	ld a, b
+	ld [H_LOADEDROMBANK], a
+	ld [MBC3RomBank], a
+
+	ld a, e
+	ld [H_VBCOPYDOUBLESRC], a
+	ld a, d
+	ld [H_VBCOPYDOUBLESRC + 1], a
+
+	ld a, l
+	ld [H_VBCOPYDOUBLEDEST], a
+	ld a, h
+	ld [H_VBCOPYDOUBLEDEST + 1], a
+
+.loop
+	ld a, c
+	cp 8
+	jr nc, .keepgoing
+
+.done
+	ld [H_VBCOPYDOUBLESIZE], a
+	call DelayFrame
+	ld a, [$ff8b]
+	ld [H_LOADEDROMBANK], a
+	ld [MBC3RomBank], a
+	pop af
+	ld [H_AUTOBGTRANSFERENABLED], a
+	ret
+
+.keepgoing
+	ld a, 8
+	ld [H_VBCOPYDOUBLESIZE], a
+	call DelayFrame
+	ld a, c
+	sub 8
+	ld c, a
+	jr .loop
+
+ClearScreenArea::
+; Clear tilemap area cxb at hl.
+	ld a, $7f ; blank tile
+	ld de, 20 ; screen width
+.y
+	push hl
+	push bc
+.x
+	ld [hli], a
+	dec c
+	jr nz, .x
+	pop bc
+	pop hl
+	add hl, de
+	dec b
+	jr nz, .y
+	ret
+
+CopyScreenTileBufferToVRAM::
+; Copy wTileMap to the BG Map starting at b * $100.
+; This is done in thirds of 6 rows, so it takes 3 frames.
+
+	ld c, 6
+
+	ld hl, $600 * 0
+	ld de, wTileMap + 20 * 6 * 0
+	call .setup
+	call DelayFrame
+
+	ld hl, $600 * 1
+	ld de, wTileMap + 20 * 6 * 1
+	call .setup
+	call DelayFrame
+
+	ld hl, $600 * 2
+	ld de, wTileMap + 20 * 6 * 2
+	call .setup
+	jp DelayFrame
+
+.setup
+	ld a, d
+	ld [H_VBCOPYBGSRC+1], a
+	call GetRowColAddressBgMap
+	ld a, l
+	ld [H_VBCOPYBGDEST], a
+	ld a, h
+	ld [H_VBCOPYBGDEST+1], a
+	ld a, c
+	ld [H_VBCOPYBGNUMROWS], a
+	ld a, e
+	ld [H_VBCOPYBGSRC], a
+	ret
+
+ClearScreen::
+; Clear wTileMap, then wait
+; for the bg map to update.
+	ld bc, 20 * 18
+	inc b
+	ld hl, wTileMap
+	ld a, $7f
+.loop
+	ld [hli], a
+	dec c
+	jr nz, .loop
+	dec b
+	jr nz, .loop
+	jp Delay3