ref: 01d6e6c75843fdc0035499ce0214c19be74a9bda
dir: /engine/gfx/dma_transfer.asm/
HDMATransferAttrmapAndTilemapToWRAMBank3:: ld hl, .Function jp CallInSafeGFXMode .Function: decoord 0, 0, wAttrmap ld hl, wScratchAttrmap call PadAttrmapForHDMATransfer decoord 0, 0 ld hl, wScratchTilemap call PadTilemapForHDMATransfer ld a, $0 ldh [rVBK], a ld hl, wScratchTilemap call HDMATransferToWRAMBank3 ld a, $1 ldh [rVBK], a ld hl, wScratchAttrmap call HDMATransferToWRAMBank3 ret HDMATransferTilemapToWRAMBank3:: ld hl, .Function jp CallInSafeGFXMode .Function: decoord 0, 0 ld hl, wScratchTilemap call PadTilemapForHDMATransfer ld a, $0 ldh [rVBK], a ld hl, wScratchTilemap call HDMATransferToWRAMBank3 ret HDMATransferAttrmapToWRAMBank3: ld hl, .Function jp CallInSafeGFXMode .Function: decoord 0, 0, wAttrmap ld hl, wScratchAttrmap call PadAttrmapForHDMATransfer ld a, $1 ldh [rVBK], a ld hl, wScratchAttrmap call HDMATransferToWRAMBank3 ret ReloadMapPart:: ld hl, .Function jp CallInSafeGFXMode .Function: decoord 0, 0, wAttrmap ld hl, wScratchAttrmap call PadAttrmapForHDMATransfer decoord 0, 0 ld hl, wScratchTilemap call PadTilemapForHDMATransfer call DelayFrame di ldh a, [rVBK] push af ld a, $1 ldh [rVBK], a ld hl, wScratchAttrmap call HDMATransfer_Wait127Scanlines_toBGMap ld a, $0 ldh [rVBK], a ld hl, wScratchTilemap call HDMATransfer_Wait127Scanlines_toBGMap pop af ldh [rVBK], a ei ret Mobile_ReloadMapPart: ld hl, ReloadMapPart ; useless ld hl, .Function jp CallInSafeGFXMode .Function: decoord 0, 0, wAttrmap ld hl, wScratchAttrmap call PadAttrmapForHDMATransfer decoord 0, 0 ld hl, wScratchTilemap call PadTilemapForHDMATransfer call DelayFrame di ldh a, [rVBK] push af ld a, $1 ldh [rVBK], a ld hl, wScratchAttrmap call HDMATransfer_NoDI ld a, $0 ldh [rVBK], a ld hl, wScratchTilemap call HDMATransfer_NoDI pop af ldh [rVBK], a ei ret Function1040d4: ; unreferenced ld hl, .Function jp CallInSafeGFXMode .Function ld a, $1 ldh [rVBK], a ld a, BANK(w3_d800) ldh [rSVBK], a ld de, w3_d800 ldh a, [hBGMapAddress + 1] ldh [rHDMA1], a ldh a, [hBGMapAddress] ldh [rHDMA2], a ld a, d ldh [rHDMA3], a ld a, e ldh [rHDMA4], a ld a, $23 ldh [hDMATransfer], a call WaitDMATransfer ret Function1040fb: ; unreferenced ld hl, .Function jp CallInSafeGFXMode .Function ld a, $1 ldh [rVBK], a ld a, BANK(w3_d800) ldh [rSVBK], a ld hl, w3_d800 call HDMATransferToWRAMBank3 ret OpenAndCloseMenu_HDMATransferTilemapAndAttrmap:: ; OpenText ld hl, .Function jp CallInSafeGFXMode .Function: ; Transfer wAttrmap and Tilemap to BGMap ; Fill vBGAttrs with $00 ; Fill vBGTiles with " " decoord 0, 0, wAttrmap ld hl, wScratchAttrmap call PadAttrmapForHDMATransfer decoord 0, 0 ld hl, wScratchTilemap call PadTilemapForHDMATransfer call DelayFrame di ldh a, [rVBK] push af ld a, $1 ldh [rVBK], a ld hl, wScratchAttrmap call HDMATransfer_Wait123Scanlines_toBGMap ld a, $0 ldh [rVBK], a ld hl, wScratchTilemap call HDMATransfer_Wait123Scanlines_toBGMap pop af ldh [rVBK], a ei ret Mobile_OpenAndCloseMenu_HDMATransferTilemapAndAttrmap: ld hl, .Function jp CallInSafeGFXMode .Function: ; Transfer wAttrmap and Tilemap to BGMap ; Fill vBGAttrs with $00 ; Fill vBGTiles with $ff decoord 0, 0, wAttrmap ld hl, wScratchAttrmap call PadAttrmapForHDMATransfer ld c, $ff decoord 0, 0 ld hl, wScratchTilemap call PadMapForHDMATransfer ld a, $1 ldh [rVBK], a ld hl, wScratchAttrmap call HDMATransfer_Wait127Scanlines_toBGMap ld a, $0 ldh [rVBK], a ld hl, wScratchTilemap call HDMATransfer_Wait127Scanlines_toBGMap ret CallInSafeGFXMode: ldh a, [hBGMapMode] push af ldh a, [hMapAnims] push af xor a ldh [hBGMapMode], a ldh [hMapAnims], a ldh a, [rSVBK] push af ld a, BANK(wScratchTilemap) ldh [rSVBK], a ldh a, [rVBK] push af call ._hl_ pop af ldh [rVBK], a pop af ldh [rSVBK], a pop af ldh [hMapAnims], a pop af ldh [hBGMapMode], a ret ._hl_ jp hl HDMATransferToWRAMBank3: call _LoadHDMAParameters ld a, $23 ldh [hDMATransfer], a WaitDMATransfer: .loop call DelayFrame ldh a, [hDMATransfer] and a jr nz, .loop ret HDMATransfer_Wait127Scanlines_toBGMap: ; HDMA transfer from hl to [hBGMapAddress] ; hBGMapAddress -> de ; 2 * SCREEN_HEIGHT -> c ldh a, [hBGMapAddress + 1] ld d, a ldh a, [hBGMapAddress] ld e, a ld c, 2 * SCREEN_HEIGHT jr HDMATransfer_Wait127Scanlines HDMATransfer_Wait123Scanlines_toBGMap: ; HDMA transfer from hl to [hBGMapAddress] ; hBGMapAddress -> de ; 2 * SCREEN_HEIGHT -> c ; $7b --> b ldh a, [hBGMapAddress + 1] ld d, a ldh a, [hBGMapAddress] ld e, a ld c, 2 * SCREEN_HEIGHT jr HDMATransfer_Wait123Scanlines HDMATransfer_NoDI: ; HDMA transfer from hl to [hBGMapAddress] ; [hBGMapAddress] --> de ; 2 * SCREEN_HEIGHT --> c ldh a, [hBGMapAddress + 1] ld d, a ldh a, [hBGMapAddress] ld e, a ld c, 2 * SCREEN_HEIGHT ; [rHDMA1, rHDMA2] = hl & $fff0 ld a, h ldh [rHDMA1], a ld a, l and $f0 ldh [rHDMA2], a ; [rHDMA3, rHDMA4] = de & $1ff0 ld a, d and $1f ldh [rHDMA3], a ld a, e and $f0 ldh [rHDMA4], a ; b = c | %10000000 ld a, c dec c or $80 ld b, a ; d = $7f - c + 1 ld a, $7f sub c ld d, a ; while [rLY] >= d: pass .loop1 ldh a, [rLY] cp d jr nc, .loop1 ; while not [rSTAT] & 3: pass .loop2 ldh a, [rSTAT] and $3 jr z, .loop2 ; load the 5th byte of HDMA ld a, b ldh [rHDMA5], a ; wait until rLY advances (c + 1) times ldh a, [rLY] inc c ld hl, rLY .loop3 cp [hl] jr z, .loop3 ld a, [hl] dec c jr nz, .loop3 ld hl, rHDMA5 res 7, [hl] ret HDMATransfer_Wait123Scanlines: ld b, $7b jr _continue_HDMATransfer HDMATransfer_Wait127Scanlines: ld b, $7f _continue_HDMATransfer: ; a lot of waiting around for hardware registers ; [rHDMA1, rHDMA2] = hl & $fff0 ld a, h ldh [rHDMA1], a ld a, l and $f0 ; high nybble ldh [rHDMA2], a ; [rHDMA3, rHDMA4] = de & $1ff0 ld a, d and $1f ; lower 5 bits ldh [rHDMA3], a ld a, e and $f0 ; high nybble ldh [rHDMA4], a ; e = c | %10000000 ld a, c dec c or $80 ld e, a ; d = b - c + 1 ld a, b sub c ld d, a ; while [rLY] >= d: pass .ly_loop ldh a, [rLY] cp d jr nc, .ly_loop di ; while [rSTAT] & 3: pass .rstat_loop_1 ldh a, [rSTAT] and $3 jr nz, .rstat_loop_1 ; while not [rSTAT] & 3: pass .rstat_loop_2 ldh a, [rSTAT] and $3 jr z, .rstat_loop_2 ; load the 5th byte of HDMA ld a, e ldh [rHDMA5], a ; wait until rLY advances (c + 1) times ldh a, [rLY] inc c ld hl, rLY .final_ly_loop cp [hl] jr z, .final_ly_loop ld a, [hl] dec c jr nz, .final_ly_loop ld hl, rHDMA5 res 7, [hl] ei ret _LoadHDMAParameters: ld a, h ldh [rHDMA1], a ld a, l ldh [rHDMA2], a ldh a, [hBGMapAddress + 1] and $1f ldh [rHDMA3], a ldh a, [hBGMapAddress] ldh [rHDMA4], a ret PadTilemapForHDMATransfer: ld c, " " jr PadMapForHDMATransfer PadAttrmapForHDMATransfer: ld c, $0 PadMapForHDMATransfer: ; pad a 20x18 map to 32x18 for HDMA transfer ; back up the padding value in c to hMapObjectIndexBuffer ldh a, [hMapObjectIndexBuffer] push af ld a, c ldh [hMapObjectIndexBuffer], a ; for each row on the screen ld c, SCREEN_HEIGHT .loop1 ; for each tile in the row ld b, SCREEN_WIDTH .loop2 ; copy from de to hl ld a, [de] inc de ld [hli], a dec b jr nz, .loop2 ; load the original padding value of c into hl for 32 - 20 = 12 rows ldh a, [hMapObjectIndexBuffer] ld b, BG_MAP_WIDTH - SCREEN_WIDTH .loop3 ld [hli], a dec b jr nz, .loop3 dec c jr nz, .loop1 ; restore the original value of hMapObjectIndexBuffer pop af ldh [hMapObjectIndexBuffer], a ret HDMATransfer2bpp:: ; 2bpp when [rLCDC] & $80 ; switch to WRAM bank 6 ldh a, [rSVBK] push af ld a, BANK(wScratchTilemap) ldh [rSVBK], a push bc push hl ; Copy c tiles of the 2bpp from b:de to wScratchTilemap ld a, b ; bank ld l, c ; number of tiles ld h, $0 ; multiply by 16 (16 bytes of a 2bpp = 8 x 8 tile) add hl, hl add hl, hl add hl, hl add hl, hl ld b, h ld c, l ld h, d ; address ld l, e ld de, wScratchTilemap call FarCopyBytes pop hl pop bc push bc call DelayFrame pop bc ld d, h ld e, l ld hl, wScratchTilemap call HDMATransfer_Wait127Scanlines ; restore the previous bank pop af ldh [rSVBK], a ret HDMATransfer1bpp:: ; 1bpp when [rLCDC] & $80 .loop ld a, c cp $10 jp c, .bankswitch jp z, .bankswitch push bc push hl push de ld c, $10 call .bankswitch pop de ld hl, $80 add hl, de ld d, h ld e, l pop hl lb bc, 1, 0 add hl, bc pop bc ld a, c sub $10 ld c, a jr .loop .bankswitch ldh a, [rSVBK] push af ld a, BANK(wScratchTilemap) ldh [rSVBK], a push bc push hl ld a, b ld l, c ld h, $0 add hl, hl ; multiply by 8 add hl, hl ; multiply by 8 add hl, hl ; multiply by 8 ld c, l ld b, h ld h, d ld l, e ld de, wScratchTilemap call FarCopyBytesDouble_DoubleBankSwitch pop hl pop bc push bc call DelayFrame pop bc ld d, h ld e, l ld hl, wScratchTilemap call HDMATransfer_Wait127Scanlines pop af ldh [rSVBK], a ret HDMATransfer_OnlyTopFourRows: ld hl, .Function jp CallInSafeGFXMode .Function: ld hl, wScratchTilemap decoord 0, 0 call .Copy ld hl, wScratchTilemap + $80 decoord 0, 0, wAttrmap call .Copy ld a, $1 ldh [rVBK], a ld c, $8 ld hl, wScratchTilemap + $80 debgcoord 0, 0, vBGMap1 call HDMATransfer_Wait127Scanlines ld a, $0 ldh [rVBK], a ld c, $8 ld hl, wScratchTilemap debgcoord 0, 0, vBGMap1 call HDMATransfer_Wait127Scanlines ret .Copy: ld b, 4 .outer_loop ld c, SCREEN_WIDTH .inner_loop ld a, [de] ld [hli], a inc de dec c jr nz, .inner_loop ld a, l add BG_MAP_WIDTH - SCREEN_WIDTH ld l, a ld a, h adc 0 ld h, a dec b jr nz, .outer_loop ret