mirror of
https://github.com/thornAvery/kep-hack.git
synced 2025-11-14 00:56:40 +13:00
home/pic.asm -> home/uncompress.asm; home/uncompress.asm -> home/pics.asm
One does the actual decompression, the other synthesizes the decompressed data.
This commit is contained in:
Rangi
parent
f9dc42a740
commit
9b144cf647
4
home.asm
4
home.asm
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@ -74,7 +74,7 @@ LoadDestinationWarpPosition::
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INCLUDE "home/pokemon.asm"
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INCLUDE "home/pokemon.asm"
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INCLUDE "home/print_bcd.asm"
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INCLUDE "home/print_bcd.asm"
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INCLUDE "home/uncompress.asm"
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INCLUDE "home/pics.asm"
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INCLUDE "data/tilesets/collision_tile_ids.asm"
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INCLUDE "data/tilesets/collision_tile_ids.asm"
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INCLUDE "home/copy2.asm"
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INCLUDE "home/copy2.asm"
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INCLUDE "home/text.asm"
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INCLUDE "home/text.asm"
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@ -103,7 +103,7 @@ UpdateSprites::
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INCLUDE "data/items/marts.asm"
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INCLUDE "data/items/marts.asm"
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INCLUDE "home/overworld_text.asm"
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INCLUDE "home/overworld_text.asm"
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INCLUDE "home/pic.asm"
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INCLUDE "home/uncompress.asm"
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ResetPlayerSpriteData::
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ResetPlayerSpriteData::
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ld hl, wSpriteStateData1
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ld hl, wSpriteStateData1
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591
home/pic.asm
591
home/pic.asm
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@ -1,591 +0,0 @@
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; bankswitches and runs _UncompressSpriteData
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; bank is given in a, sprite input stream is pointed to in wSpriteInputPtr
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UncompressSpriteData::
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ld b, a
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ld a, [hLoadedROMBank]
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push af
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ld a, b
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ld [hLoadedROMBank], a
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ld [MBC1RomBank], a
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ld a, SRAM_ENABLE
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ld [MBC1SRamEnable], a
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xor a
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ld [MBC1SRamBank], a
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call _UncompressSpriteData
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pop af
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ld [hLoadedROMBank], a
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ld [MBC1RomBank], a
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ret
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; initializes necessary data to load a sprite and runs UncompressSpriteDataLoop
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_UncompressSpriteData::
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ld hl, sSpriteBuffer1
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ld c, (2*SPRITEBUFFERSIZE) % $100
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ld b, (2*SPRITEBUFFERSIZE) / $100
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xor a
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call FillMemory ; clear sprite buffer 1 and 2
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ld a, $1
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ld [wSpriteInputBitCounter], a
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ld a, $3
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ld [wSpriteOutputBitOffset], a
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xor a
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ld [wSpriteCurPosX], a
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ld [wSpriteCurPosY], a
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ld [wSpriteLoadFlags], a
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call ReadNextInputByte ; first byte of input determines sprite width (high nybble) and height (low nybble) in tiles (8x8 pixels)
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ld b, a
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and $f
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add a
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add a
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add a
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ld [wSpriteHeight], a
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ld a, b
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swap a
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and $f
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add a
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add a
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add a
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ld [wSpriteWidth], a
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call ReadNextInputBit
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ld [wSpriteLoadFlags], a ; initialite bit1 to 0 and bit0 to the first input bit
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; this will load two chunks of data to sSpriteBuffer1 and sSpriteBuffer2
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; bit 0 decides in which one the first chunk is placed
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; fall through
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; uncompresses a chunk from the sprite input data stream (pointed to at wd0da) into sSpriteBuffer1 or sSpriteBuffer2
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; each chunk is a 1bpp sprite. A 2bpp sprite consist of two chunks which are merged afterwards
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; note that this is an endless loop which is terminated during a call to MoveToNextBufferPosition by manipulating the stack
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UncompressSpriteDataLoop::
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ld hl, sSpriteBuffer1
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ld a, [wSpriteLoadFlags]
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bit 0, a
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jr z, .useSpriteBuffer1 ; check which buffer to use
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ld hl, sSpriteBuffer2
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.useSpriteBuffer1
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call StoreSpriteOutputPointer
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ld a, [wSpriteLoadFlags]
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bit 1, a
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jr z, .startDecompression ; check if last iteration
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call ReadNextInputBit ; if last chunk, read 1-2 bit unpacking mode
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and a
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jr z, .unpackingMode0 ; 0 -> mode 0
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call ReadNextInputBit ; 1 0 -> mode 1
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inc a ; 1 1 -> mode 2
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.unpackingMode0
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ld [wSpriteUnpackMode], a
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.startDecompression
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call ReadNextInputBit
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and a
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jr z, .readRLEncodedZeros ; if first bit is 0, the input starts with zeroes, otherwise with (non-zero) input
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.readNextInput
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call ReadNextInputBit
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ld c, a
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call ReadNextInputBit
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sla c
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or c ; read next two bits into c
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and a
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jr z, .readRLEncodedZeros ; 00 -> RLEncoded zeroes following
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call WriteSpriteBitsToBuffer ; otherwise write input to output and repeat
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call MoveToNextBufferPosition
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jr .readNextInput
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.readRLEncodedZeros
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ld c, $0 ; number of zeroes it length encoded, the number
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.countConsecutiveOnesLoop ; of consecutive ones determines the number of bits the number has
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call ReadNextInputBit
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and a
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jr z, .countConsecutiveOnesFinished
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inc c
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jr .countConsecutiveOnesLoop
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.countConsecutiveOnesFinished
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ld a, c
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add a
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ld hl, LengthEncodingOffsetList
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add l
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ld l, a
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jr nc, .noCarry
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inc h
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.noCarry
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ld a, [hli] ; read offset that is added to the number later on
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ld e, a ; adding an offset of 2^length - 1 makes every integer uniquely
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ld d, [hl] ; representable in the length encoding and saves bits
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push de
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inc c
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ld e, $0
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ld d, e
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.readNumberOfZerosLoop ; reads the next c+1 bits of input
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call ReadNextInputBit
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or e
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ld e, a
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dec c
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jr z, .readNumberOfZerosDone
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sla e
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rl d
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jr .readNumberOfZerosLoop
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.readNumberOfZerosDone
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pop hl ; add the offset
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add hl, de
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ld e, l
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ld d, h
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.writeZerosLoop
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ld b, e
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xor a ; write 00 to buffer
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call WriteSpriteBitsToBuffer
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ld e, b
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call MoveToNextBufferPosition
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dec de
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ld a, d
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and a
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jr nz, .continueLoop
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ld a, e
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and a
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.continueLoop
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jr nz, .writeZerosLoop
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jr .readNextInput
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; moves output pointer to next position
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; also cancels the calling function if the all output is done (by removing the return pointer from stack)
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; and calls postprocessing functions according to the unpack mode
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MoveToNextBufferPosition::
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ld a, [wSpriteHeight]
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ld b, a
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ld a, [wSpriteCurPosY]
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inc a
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cp b
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jr z, .curColumnDone
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ld [wSpriteCurPosY], a
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ld a, [wSpriteOutputPtr]
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inc a
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ld [wSpriteOutputPtr], a
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ret nz
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ld a, [wSpriteOutputPtr+1]
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inc a
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ld [wSpriteOutputPtr+1], a
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ret
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.curColumnDone
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xor a
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ld [wSpriteCurPosY], a
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ld a, [wSpriteOutputBitOffset]
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and a
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jr z, .bitOffsetsDone
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dec a
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ld [wSpriteOutputBitOffset], a
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ld hl, wSpriteOutputPtrCached
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ld a, [hli]
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ld [wSpriteOutputPtr], a
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ld a, [hl]
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ld [wSpriteOutputPtr+1], a
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ret
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.bitOffsetsDone
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ld a, $3
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ld [wSpriteOutputBitOffset], a
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ld a, [wSpriteCurPosX]
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add $8
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ld [wSpriteCurPosX], a
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ld b, a
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ld a, [wSpriteWidth]
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cp b
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jr z, .allColumnsDone
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ld a, [wSpriteOutputPtr]
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ld l, a
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ld a, [wSpriteOutputPtr+1]
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ld h, a
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inc hl
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jp StoreSpriteOutputPointer
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.allColumnsDone
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pop hl
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xor a
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ld [wSpriteCurPosX], a
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ld a, [wSpriteLoadFlags]
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bit 1, a
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jr nz, .done ; test if there is one more sprite to go
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xor $1
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set 1, a
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ld [wSpriteLoadFlags], a
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jp UncompressSpriteDataLoop
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.done
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jp UnpackSprite
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; writes 2 bits (from a) to the output buffer (pointed to from wSpriteOutputPtr)
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WriteSpriteBitsToBuffer::
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ld e, a
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ld a, [wSpriteOutputBitOffset]
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and a
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jr z, .offset0
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cp $2
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jr c, .offset1
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jr z, .offset2
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rrc e ; offset 3
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rrc e
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jr .offset0
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.offset1
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sla e
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sla e
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jr .offset0
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.offset2
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swap e
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.offset0
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ld a, [wSpriteOutputPtr]
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ld l, a
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ld a, [wSpriteOutputPtr+1]
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ld h, a
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ld a, [hl]
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or e
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ld [hl], a
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ret
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; reads next bit from input stream and returns it in a
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ReadNextInputBit::
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ld a, [wSpriteInputBitCounter]
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dec a
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jr nz, .curByteHasMoreBitsToRead
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call ReadNextInputByte
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ld [wSpriteInputCurByte], a
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ld a, $8
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.curByteHasMoreBitsToRead
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ld [wSpriteInputBitCounter], a
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ld a, [wSpriteInputCurByte]
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rlca
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ld [wSpriteInputCurByte], a
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and $1
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ret
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; reads next byte from input stream and returns it in a
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ReadNextInputByte::
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ld a, [wSpriteInputPtr]
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ld l, a
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ld a, [wSpriteInputPtr+1]
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ld h, a
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ld a, [hli]
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ld b, a
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ld a, l
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ld [wSpriteInputPtr], a
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ld a, h
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ld [wSpriteInputPtr+1], a
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ld a, b
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ret
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; the nth item is 2^n - 1
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LengthEncodingOffsetList::
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dw %0000000000000001
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dw %0000000000000011
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dw %0000000000000111
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dw %0000000000001111
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dw %0000000000011111
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dw %0000000000111111
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dw %0000000001111111
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dw %0000000011111111
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dw %0000000111111111
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dw %0000001111111111
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dw %0000011111111111
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dw %0000111111111111
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dw %0001111111111111
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dw %0011111111111111
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dw %0111111111111111
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dw %1111111111111111
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; unpacks the sprite data depending on the unpack mode
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UnpackSprite::
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ld a, [wSpriteUnpackMode]
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cp $2
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jp z, UnpackSpriteMode2
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and a
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jp nz, XorSpriteChunks
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ld hl, sSpriteBuffer1
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call SpriteDifferentialDecode
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ld hl, sSpriteBuffer2
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; fall through
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; decodes differential encoded sprite data
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; input bit value 0 preserves the current bit value and input bit value 1 toggles it (starting from initial value 0).
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SpriteDifferentialDecode::
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xor a
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ld [wSpriteCurPosX], a
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ld [wSpriteCurPosY], a
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call StoreSpriteOutputPointer
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ld a, [wSpriteFlipped]
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and a
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jr z, .notFlipped
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ld hl, DecodeNybble0TableFlipped
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ld de, DecodeNybble1TableFlipped
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jr .storeDecodeTablesPointers
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.notFlipped
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ld hl, DecodeNybble0Table
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ld de, DecodeNybble1Table
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.storeDecodeTablesPointers
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ld a, l
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ld [wSpriteDecodeTable0Ptr], a
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ld a, h
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ld [wSpriteDecodeTable0Ptr+1], a
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ld a, e
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ld [wSpriteDecodeTable1Ptr], a
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ld a, d
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ld [wSpriteDecodeTable1Ptr+1], a
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ld e, $0 ; last decoded nybble, initialized to 0
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.decodeNextByteLoop
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ld a, [wSpriteOutputPtr]
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ld l, a
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ld a, [wSpriteOutputPtr+1]
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ld h, a
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ld a, [hl]
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ld b, a
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swap a
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and $f
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call DifferentialDecodeNybble ; decode high nybble
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swap a
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ld d, a
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ld a, b
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and $f
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call DifferentialDecodeNybble ; decode low nybble
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or d
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ld b, a
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ld a, [wSpriteOutputPtr]
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ld l, a
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ld a, [wSpriteOutputPtr+1]
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ld h, a
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ld a, b
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ld [hl], a ; write back decoded data
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ld a, [wSpriteHeight]
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add l ; move on to next column
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jr nc, .noCarry
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inc h
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.noCarry
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ld [wSpriteOutputPtr], a
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ld a, h
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ld [wSpriteOutputPtr+1], a
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ld a, [wSpriteCurPosX]
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add $8
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ld [wSpriteCurPosX], a
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ld b, a
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ld a, [wSpriteWidth]
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cp b
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jr nz, .decodeNextByteLoop ; test if current row is done
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xor a
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ld e, a
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ld [wSpriteCurPosX], a
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ld a, [wSpriteCurPosY] ; move on to next row
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inc a
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ld [wSpriteCurPosY], a
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ld b, a
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ld a, [wSpriteHeight]
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cp b
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jr z, .done ; test if all rows finished
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ld a, [wSpriteOutputPtrCached]
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ld l, a
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ld a, [wSpriteOutputPtrCached+1]
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|
||||||
ld h, a
|
|
||||||
inc hl
|
|
||||||
call StoreSpriteOutputPointer
|
|
||||||
jr .decodeNextByteLoop
|
|
||||||
.done
|
|
||||||
xor a
|
|
||||||
ld [wSpriteCurPosY], a
|
|
||||||
ret
|
|
||||||
|
|
||||||
; decodes the nybble stored in a. Last decoded data is assumed to be in e (needed to determine if initial value is 0 or 1)
|
|
||||||
DifferentialDecodeNybble::
|
|
||||||
srl a ; c=a%2, a/=2
|
|
||||||
ld c, $0
|
|
||||||
jr nc, .evenNumber
|
|
||||||
ld c, $1
|
|
||||||
.evenNumber
|
|
||||||
ld l, a
|
|
||||||
ld a, [wSpriteFlipped]
|
|
||||||
and a
|
|
||||||
jr z, .notFlipped ; determine if initial value is 0 or one
|
|
||||||
bit 3, e ; if flipped, consider MSB of last data
|
|
||||||
jr .selectLookupTable
|
|
||||||
.notFlipped
|
|
||||||
bit 0, e ; else consider LSB
|
|
||||||
.selectLookupTable
|
|
||||||
ld e, l
|
|
||||||
jr nz, .initialValue1 ; load the appropriate table
|
|
||||||
ld a, [wSpriteDecodeTable0Ptr]
|
|
||||||
ld l, a
|
|
||||||
ld a, [wSpriteDecodeTable0Ptr+1]
|
|
||||||
jr .tableLookup
|
|
||||||
.initialValue1
|
|
||||||
ld a, [wSpriteDecodeTable1Ptr]
|
|
||||||
ld l, a
|
|
||||||
ld a, [wSpriteDecodeTable1Ptr+1]
|
|
||||||
.tableLookup
|
|
||||||
ld h, a
|
|
||||||
ld a, e
|
|
||||||
add l
|
|
||||||
ld l, a
|
|
||||||
jr nc, .noCarry
|
|
||||||
inc h
|
|
||||||
.noCarry
|
|
||||||
ld a, [hl]
|
|
||||||
bit 0, c
|
|
||||||
jr nz, .selectLowNybble
|
|
||||||
swap a ; select high nybble
|
|
||||||
.selectLowNybble
|
|
||||||
and $f
|
|
||||||
ld e, a ; update last decoded data
|
|
||||||
ret
|
|
||||||
|
|
||||||
DecodeNybble0Table::
|
|
||||||
dn $0, $1
|
|
||||||
dn $3, $2
|
|
||||||
dn $7, $6
|
|
||||||
dn $4, $5
|
|
||||||
dn $f, $e
|
|
||||||
dn $c, $d
|
|
||||||
dn $8, $9
|
|
||||||
dn $b, $a
|
|
||||||
DecodeNybble1Table::
|
|
||||||
dn $f, $e
|
|
||||||
dn $c, $d
|
|
||||||
dn $8, $9
|
|
||||||
dn $b, $a
|
|
||||||
dn $0, $1
|
|
||||||
dn $3, $2
|
|
||||||
dn $7, $6
|
|
||||||
dn $4, $5
|
|
||||||
DecodeNybble0TableFlipped::
|
|
||||||
dn $0, $8
|
|
||||||
dn $c, $4
|
|
||||||
dn $e, $6
|
|
||||||
dn $2, $a
|
|
||||||
dn $f, $7
|
|
||||||
dn $3, $b
|
|
||||||
dn $1, $9
|
|
||||||
dn $d, $5
|
|
||||||
DecodeNybble1TableFlipped::
|
|
||||||
dn $f, $7
|
|
||||||
dn $3, $b
|
|
||||||
dn $1, $9
|
|
||||||
dn $d, $5
|
|
||||||
dn $0, $8
|
|
||||||
dn $c, $4
|
|
||||||
dn $e, $6
|
|
||||||
dn $2, $a
|
|
||||||
|
|
||||||
; combines the two loaded chunks with xor (the chunk loaded second is the destination). The source chunk is differeintial decoded beforehand.
|
|
||||||
XorSpriteChunks::
|
|
||||||
xor a
|
|
||||||
ld [wSpriteCurPosX], a
|
|
||||||
ld [wSpriteCurPosY], a
|
|
||||||
call ResetSpriteBufferPointers
|
|
||||||
ld a, [wSpriteOutputPtr] ; points to buffer 1 or 2, depending on flags
|
|
||||||
ld l, a
|
|
||||||
ld a, [wSpriteOutputPtr+1]
|
|
||||||
ld h, a
|
|
||||||
call SpriteDifferentialDecode ; decode buffer 1 or 2, depending on flags
|
|
||||||
call ResetSpriteBufferPointers
|
|
||||||
ld a, [wSpriteOutputPtr] ; source buffer, points to buffer 1 or 2, depending on flags
|
|
||||||
ld l, a
|
|
||||||
ld a, [wSpriteOutputPtr+1]
|
|
||||||
ld h, a
|
|
||||||
ld a, [wSpriteOutputPtrCached] ; destination buffer, points to buffer 2 or 1, depending on flags
|
|
||||||
ld e, a
|
|
||||||
ld a, [wSpriteOutputPtrCached+1]
|
|
||||||
ld d, a
|
|
||||||
.xorChunksLoop
|
|
||||||
ld a, [wSpriteFlipped]
|
|
||||||
and a
|
|
||||||
jr z, .notFlipped
|
|
||||||
push de
|
|
||||||
ld a, [de]
|
|
||||||
ld b, a
|
|
||||||
swap a
|
|
||||||
and $f
|
|
||||||
call ReverseNybble ; if flipped reverse the nybbles in the destination buffer
|
|
||||||
swap a
|
|
||||||
ld c, a
|
|
||||||
ld a, b
|
|
||||||
and $f
|
|
||||||
call ReverseNybble
|
|
||||||
or c
|
|
||||||
pop de
|
|
||||||
ld [de], a
|
|
||||||
.notFlipped
|
|
||||||
ld a, [hli]
|
|
||||||
ld b, a
|
|
||||||
ld a, [de]
|
|
||||||
xor b
|
|
||||||
ld [de], a
|
|
||||||
inc de
|
|
||||||
ld a, [wSpriteCurPosY]
|
|
||||||
inc a
|
|
||||||
ld [wSpriteCurPosY], a ; go to next row
|
|
||||||
ld b, a
|
|
||||||
ld a, [wSpriteHeight]
|
|
||||||
cp b
|
|
||||||
jr nz, .xorChunksLoop ; test if column finished
|
|
||||||
xor a
|
|
||||||
ld [wSpriteCurPosY], a
|
|
||||||
ld a, [wSpriteCurPosX]
|
|
||||||
add $8
|
|
||||||
ld [wSpriteCurPosX], a ; go to next column
|
|
||||||
ld b, a
|
|
||||||
ld a, [wSpriteWidth]
|
|
||||||
cp b
|
|
||||||
jr nz, .xorChunksLoop ; test if all columns finished
|
|
||||||
xor a
|
|
||||||
ld [wSpriteCurPosX], a
|
|
||||||
ret
|
|
||||||
|
|
||||||
; reverses the bits in the nybble given in register a
|
|
||||||
ReverseNybble::
|
|
||||||
ld de, NybbleReverseTable
|
|
||||||
add e
|
|
||||||
ld e, a
|
|
||||||
jr nc, .noCarry
|
|
||||||
inc d
|
|
||||||
.noCarry
|
|
||||||
ld a, [de]
|
|
||||||
ret
|
|
||||||
|
|
||||||
; resets sprite buffer pointers to buffer 1 and 2, depending on wSpriteLoadFlags
|
|
||||||
ResetSpriteBufferPointers::
|
|
||||||
ld a, [wSpriteLoadFlags]
|
|
||||||
bit 0, a
|
|
||||||
jr nz, .buffer2Selected
|
|
||||||
ld de, sSpriteBuffer1
|
|
||||||
ld hl, sSpriteBuffer2
|
|
||||||
jr .storeBufferPointers
|
|
||||||
.buffer2Selected
|
|
||||||
ld de, sSpriteBuffer2
|
|
||||||
ld hl, sSpriteBuffer1
|
|
||||||
.storeBufferPointers
|
|
||||||
ld a, l
|
|
||||||
ld [wSpriteOutputPtr], a
|
|
||||||
ld a, h
|
|
||||||
ld [wSpriteOutputPtr+1], a
|
|
||||||
ld a, e
|
|
||||||
ld [wSpriteOutputPtrCached], a
|
|
||||||
ld a, d
|
|
||||||
ld [wSpriteOutputPtrCached+1], a
|
|
||||||
ret
|
|
||||||
|
|
||||||
; maps each nybble to its reverse
|
|
||||||
NybbleReverseTable::
|
|
||||||
db $0, $8, $4, $c, $2, $a, $6 ,$e, $1, $9, $5, $d, $3, $b, $7 ,$f
|
|
||||||
|
|
||||||
; combines the two loaded chunks with xor (the chunk loaded second is the destination). Both chunks are differeintial decoded beforehand.
|
|
||||||
UnpackSpriteMode2::
|
|
||||||
call ResetSpriteBufferPointers
|
|
||||||
ld a, [wSpriteFlipped]
|
|
||||||
push af
|
|
||||||
xor a
|
|
||||||
ld [wSpriteFlipped], a ; temporarily clear flipped flag for decoding the destination chunk
|
|
||||||
ld a, [wSpriteOutputPtrCached]
|
|
||||||
ld l, a
|
|
||||||
ld a, [wSpriteOutputPtrCached+1]
|
|
||||||
ld h, a
|
|
||||||
call SpriteDifferentialDecode
|
|
||||||
call ResetSpriteBufferPointers
|
|
||||||
pop af
|
|
||||||
ld [wSpriteFlipped], a
|
|
||||||
jp XorSpriteChunks
|
|
||||||
|
|
||||||
; stores hl into the output pointers
|
|
||||||
StoreSpriteOutputPointer::
|
|
||||||
ld a, l
|
|
||||||
ld [wSpriteOutputPtr], a
|
|
||||||
ld [wSpriteOutputPtrCached], a
|
|
||||||
ld a, h
|
|
||||||
ld [wSpriteOutputPtr+1], a
|
|
||||||
ld [wSpriteOutputPtrCached+1], a
|
|
||||||
ret
|
|
||||||
196
home/pics.asm
Normal file
196
home/pics.asm
Normal file
|
|
@ -0,0 +1,196 @@
|
||||||
|
; uncompresses the front or back sprite of the specified mon
|
||||||
|
; assumes the corresponding mon header is already loaded
|
||||||
|
; hl contains offset to sprite pointer ($b for front or $d for back)
|
||||||
|
UncompressMonSprite::
|
||||||
|
ld bc, wMonHeader
|
||||||
|
add hl, bc
|
||||||
|
ld a, [hli]
|
||||||
|
ld [wSpriteInputPtr], a ; fetch sprite input pointer
|
||||||
|
ld a, [hl]
|
||||||
|
ld [wSpriteInputPtr+1], a
|
||||||
|
; define (by index number) the bank that a pokemon's image is in
|
||||||
|
; index = Mew, bank 1
|
||||||
|
; index = Kabutops fossil, bank $B
|
||||||
|
; index < $1F, bank 9
|
||||||
|
; $1F ≤ index < $4A, bank $A
|
||||||
|
; $4A ≤ index < $74, bank $B
|
||||||
|
; $74 ≤ index < $99, bank $C
|
||||||
|
; $99 ≤ index, bank $D
|
||||||
|
ld a, [wcf91] ; XXX name for this ram location
|
||||||
|
ld b, a
|
||||||
|
cp MEW
|
||||||
|
ld a, BANK(MewPicFront)
|
||||||
|
jr z, .GotBank
|
||||||
|
ld a, b
|
||||||
|
cp FOSSIL_KABUTOPS
|
||||||
|
ld a, BANK(FossilKabutopsPic)
|
||||||
|
jr z, .GotBank
|
||||||
|
ld a, b
|
||||||
|
cp TANGELA + 1
|
||||||
|
ld a, BANK(TangelaPicFront)
|
||||||
|
jr c, .GotBank
|
||||||
|
ld a, b
|
||||||
|
cp MOLTRES + 1
|
||||||
|
ld a, BANK(MoltresPicFront)
|
||||||
|
jr c, .GotBank
|
||||||
|
ld a, b
|
||||||
|
cp BEEDRILL + 2
|
||||||
|
ld a, BANK(BeedrillPicFront)
|
||||||
|
jr c, .GotBank
|
||||||
|
ld a, b
|
||||||
|
cp STARMIE + 1
|
||||||
|
ld a, BANK(StarmiePicFront)
|
||||||
|
jr c, .GotBank
|
||||||
|
ld a, BANK(VictreebelPicFront)
|
||||||
|
.GotBank
|
||||||
|
jp UncompressSpriteData
|
||||||
|
|
||||||
|
; de: destination location
|
||||||
|
LoadMonFrontSprite::
|
||||||
|
push de
|
||||||
|
ld hl, wMonHFrontSprite - wMonHeader
|
||||||
|
call UncompressMonSprite
|
||||||
|
ld hl, wMonHSpriteDim
|
||||||
|
ld a, [hli]
|
||||||
|
ld c, a
|
||||||
|
pop de
|
||||||
|
; fall through
|
||||||
|
|
||||||
|
; postprocesses uncompressed sprite chunks to a 2bpp sprite and loads it into video ram
|
||||||
|
; calculates alignment parameters to place both sprite chunks in the center of the 7*7 tile sprite buffers
|
||||||
|
; de: destination location
|
||||||
|
; a,c: sprite dimensions (in tiles of 8x8 each)
|
||||||
|
LoadUncompressedSpriteData::
|
||||||
|
push de
|
||||||
|
and $f
|
||||||
|
ld [hSpriteWidth], a ; each byte contains 8 pixels (in 1bpp), so tiles=bytes for width
|
||||||
|
ld b, a
|
||||||
|
ld a, $7
|
||||||
|
sub b ; 7-w
|
||||||
|
inc a ; 8-w
|
||||||
|
srl a ; (8-w)/2 ; horizontal center (in tiles, rounded up)
|
||||||
|
ld b, a
|
||||||
|
add a
|
||||||
|
add a
|
||||||
|
add a
|
||||||
|
sub b ; 7*((8-w)/2) ; skip for horizontal center (in tiles)
|
||||||
|
ld [hSpriteOffset], a
|
||||||
|
ld a, c
|
||||||
|
swap a
|
||||||
|
and $f
|
||||||
|
ld b, a
|
||||||
|
add a
|
||||||
|
add a
|
||||||
|
add a ; 8*tiles is height in bytes
|
||||||
|
ld [hSpriteHeight], a
|
||||||
|
ld a, $7
|
||||||
|
sub b ; 7-h ; skip for vertical center (in tiles, relative to current column)
|
||||||
|
ld b, a
|
||||||
|
ld a, [hSpriteOffset]
|
||||||
|
add b ; 7*((8-w)/2) + 7-h ; combined overall offset (in tiles)
|
||||||
|
add a
|
||||||
|
add a
|
||||||
|
add a ; 8*(7*((8-w)/2) + 7-h) ; combined overall offset (in bytes)
|
||||||
|
ld [hSpriteOffset], a
|
||||||
|
xor a
|
||||||
|
ld [$4000], a
|
||||||
|
ld hl, sSpriteBuffer0
|
||||||
|
call ZeroSpriteBuffer ; zero buffer 0
|
||||||
|
ld de, sSpriteBuffer1
|
||||||
|
ld hl, sSpriteBuffer0
|
||||||
|
call AlignSpriteDataCentered ; copy and align buffer 1 to 0 (containing the MSB of the 2bpp sprite)
|
||||||
|
ld hl, sSpriteBuffer1
|
||||||
|
call ZeroSpriteBuffer ; zero buffer 1
|
||||||
|
ld de, sSpriteBuffer2
|
||||||
|
ld hl, sSpriteBuffer1
|
||||||
|
call AlignSpriteDataCentered ; copy and align buffer 2 to 1 (containing the LSB of the 2bpp sprite)
|
||||||
|
pop de
|
||||||
|
jp InterlaceMergeSpriteBuffers
|
||||||
|
|
||||||
|
; copies and aligns the sprite data properly inside the sprite buffer
|
||||||
|
; sprite buffers are 7*7 tiles in size, the loaded sprite is centered within this area
|
||||||
|
AlignSpriteDataCentered::
|
||||||
|
ld a, [hSpriteOffset]
|
||||||
|
ld b, $0
|
||||||
|
ld c, a
|
||||||
|
add hl, bc
|
||||||
|
ld a, [hSpriteWidth]
|
||||||
|
.columnLoop
|
||||||
|
push af
|
||||||
|
push hl
|
||||||
|
ld a, [hSpriteHeight]
|
||||||
|
ld c, a
|
||||||
|
.columnInnerLoop
|
||||||
|
ld a, [de]
|
||||||
|
inc de
|
||||||
|
ld [hli], a
|
||||||
|
dec c
|
||||||
|
jr nz, .columnInnerLoop
|
||||||
|
pop hl
|
||||||
|
ld bc, 7*8 ; 7 tiles
|
||||||
|
add hl, bc ; advance one full column
|
||||||
|
pop af
|
||||||
|
dec a
|
||||||
|
jr nz, .columnLoop
|
||||||
|
ret
|
||||||
|
|
||||||
|
; fills the sprite buffer (pointed to in hl) with zeros
|
||||||
|
ZeroSpriteBuffer::
|
||||||
|
ld bc, SPRITEBUFFERSIZE
|
||||||
|
.nextByteLoop
|
||||||
|
xor a
|
||||||
|
ld [hli], a
|
||||||
|
dec bc
|
||||||
|
ld a, b
|
||||||
|
or c
|
||||||
|
jr nz, .nextByteLoop
|
||||||
|
ret
|
||||||
|
|
||||||
|
; combines the (7*7 tiles, 1bpp) sprite chunks in buffer 0 and 1 into a 2bpp sprite located in buffer 1 through 2
|
||||||
|
; in the resulting sprite, the rows of the two source sprites are interlaced
|
||||||
|
; de: output address
|
||||||
|
InterlaceMergeSpriteBuffers::
|
||||||
|
xor a
|
||||||
|
ld [$4000], a
|
||||||
|
push de
|
||||||
|
ld hl, sSpriteBuffer2 + (SPRITEBUFFERSIZE - 1) ; destination: end of buffer 2
|
||||||
|
ld de, sSpriteBuffer1 + (SPRITEBUFFERSIZE - 1) ; source 2: end of buffer 1
|
||||||
|
ld bc, sSpriteBuffer0 + (SPRITEBUFFERSIZE - 1) ; source 1: end of buffer 0
|
||||||
|
ld a, SPRITEBUFFERSIZE/2 ; $c4
|
||||||
|
ld [hSpriteInterlaceCounter], a
|
||||||
|
.interlaceLoop
|
||||||
|
ld a, [de]
|
||||||
|
dec de
|
||||||
|
ld [hld], a ; write byte of source 2
|
||||||
|
ld a, [bc]
|
||||||
|
dec bc
|
||||||
|
ld [hld], a ; write byte of source 1
|
||||||
|
ld a, [de]
|
||||||
|
dec de
|
||||||
|
ld [hld], a ; write byte of source 2
|
||||||
|
ld a, [bc]
|
||||||
|
dec bc
|
||||||
|
ld [hld], a ; write byte of source 1
|
||||||
|
ld a, [hSpriteInterlaceCounter]
|
||||||
|
dec a
|
||||||
|
ld [hSpriteInterlaceCounter], a
|
||||||
|
jr nz, .interlaceLoop
|
||||||
|
ld a, [wSpriteFlipped]
|
||||||
|
and a
|
||||||
|
jr z, .notFlipped
|
||||||
|
ld bc, 2*SPRITEBUFFERSIZE
|
||||||
|
ld hl, sSpriteBuffer1
|
||||||
|
.swapLoop
|
||||||
|
swap [hl] ; if flipped swap nybbles in all bytes
|
||||||
|
inc hl
|
||||||
|
dec bc
|
||||||
|
ld a, b
|
||||||
|
or c
|
||||||
|
jr nz, .swapLoop
|
||||||
|
.notFlipped
|
||||||
|
pop hl
|
||||||
|
ld de, sSpriteBuffer1
|
||||||
|
ld c, (2*SPRITEBUFFERSIZE)/16 ; $31, number of 16 byte chunks to be copied
|
||||||
|
ld a, [hLoadedROMBank]
|
||||||
|
ld b, a
|
||||||
|
jp CopyVideoData
|
||||||
|
|
@ -1,196 +1,591 @@
|
||||||
; uncompresses the front or back sprite of the specified mon
|
; bankswitches and runs _UncompressSpriteData
|
||||||
; assumes the corresponding mon header is already loaded
|
; bank is given in a, sprite input stream is pointed to in wSpriteInputPtr
|
||||||
; hl contains offset to sprite pointer ($b for front or $d for back)
|
UncompressSpriteData::
|
||||||
UncompressMonSprite::
|
|
||||||
ld bc, wMonHeader
|
|
||||||
add hl, bc
|
|
||||||
ld a, [hli]
|
|
||||||
ld [wSpriteInputPtr], a ; fetch sprite input pointer
|
|
||||||
ld a, [hl]
|
|
||||||
ld [wSpriteInputPtr+1], a
|
|
||||||
; define (by index number) the bank that a pokemon's image is in
|
|
||||||
; index = Mew, bank 1
|
|
||||||
; index = Kabutops fossil, bank $B
|
|
||||||
; index < $1F, bank 9
|
|
||||||
; $1F ≤ index < $4A, bank $A
|
|
||||||
; $4A ≤ index < $74, bank $B
|
|
||||||
; $74 ≤ index < $99, bank $C
|
|
||||||
; $99 ≤ index, bank $D
|
|
||||||
ld a, [wcf91] ; XXX name for this ram location
|
|
||||||
ld b, a
|
ld b, a
|
||||||
cp MEW
|
ld a, [hLoadedROMBank]
|
||||||
ld a, BANK(MewPicFront)
|
push af
|
||||||
jr z, .GotBank
|
|
||||||
ld a, b
|
ld a, b
|
||||||
cp FOSSIL_KABUTOPS
|
ld [hLoadedROMBank], a
|
||||||
ld a, BANK(FossilKabutopsPic)
|
ld [MBC1RomBank], a
|
||||||
jr z, .GotBank
|
ld a, SRAM_ENABLE
|
||||||
ld a, b
|
ld [MBC1SRamEnable], a
|
||||||
cp TANGELA + 1
|
xor a
|
||||||
ld a, BANK(TangelaPicFront)
|
ld [MBC1SRamBank], a
|
||||||
jr c, .GotBank
|
call _UncompressSpriteData
|
||||||
ld a, b
|
pop af
|
||||||
cp MOLTRES + 1
|
ld [hLoadedROMBank], a
|
||||||
ld a, BANK(MoltresPicFront)
|
ld [MBC1RomBank], a
|
||||||
jr c, .GotBank
|
ret
|
||||||
ld a, b
|
|
||||||
cp BEEDRILL + 2
|
|
||||||
ld a, BANK(BeedrillPicFront)
|
|
||||||
jr c, .GotBank
|
|
||||||
ld a, b
|
|
||||||
cp STARMIE + 1
|
|
||||||
ld a, BANK(StarmiePicFront)
|
|
||||||
jr c, .GotBank
|
|
||||||
ld a, BANK(VictreebelPicFront)
|
|
||||||
.GotBank
|
|
||||||
jp UncompressSpriteData
|
|
||||||
|
|
||||||
; de: destination location
|
; initializes necessary data to load a sprite and runs UncompressSpriteDataLoop
|
||||||
LoadMonFrontSprite::
|
_UncompressSpriteData::
|
||||||
push de
|
ld hl, sSpriteBuffer1
|
||||||
ld hl, wMonHFrontSprite - wMonHeader
|
ld c, (2*SPRITEBUFFERSIZE) % $100
|
||||||
call UncompressMonSprite
|
ld b, (2*SPRITEBUFFERSIZE) / $100
|
||||||
ld hl, wMonHSpriteDim
|
xor a
|
||||||
ld a, [hli]
|
call FillMemory ; clear sprite buffer 1 and 2
|
||||||
ld c, a
|
ld a, $1
|
||||||
pop de
|
ld [wSpriteInputBitCounter], a
|
||||||
; fall through
|
ld a, $3
|
||||||
|
ld [wSpriteOutputBitOffset], a
|
||||||
; postprocesses uncompressed sprite chunks to a 2bpp sprite and loads it into video ram
|
xor a
|
||||||
; calculates alignment parameters to place both sprite chunks in the center of the 7*7 tile sprite buffers
|
ld [wSpriteCurPosX], a
|
||||||
; de: destination location
|
ld [wSpriteCurPosY], a
|
||||||
; a,c: sprite dimensions (in tiles of 8x8 each)
|
ld [wSpriteLoadFlags], a
|
||||||
LoadUncompressedSpriteData::
|
call ReadNextInputByte ; first byte of input determines sprite width (high nybble) and height (low nybble) in tiles (8x8 pixels)
|
||||||
push de
|
ld b, a
|
||||||
and $f
|
and $f
|
||||||
ld [hSpriteWidth], a ; each byte contains 8 pixels (in 1bpp), so tiles=bytes for width
|
|
||||||
ld b, a
|
|
||||||
ld a, $7
|
|
||||||
sub b ; 7-w
|
|
||||||
inc a ; 8-w
|
|
||||||
srl a ; (8-w)/2 ; horizontal center (in tiles, rounded up)
|
|
||||||
ld b, a
|
|
||||||
add a
|
add a
|
||||||
add a
|
add a
|
||||||
add a
|
add a
|
||||||
sub b ; 7*((8-w)/2) ; skip for horizontal center (in tiles)
|
ld [wSpriteHeight], a
|
||||||
ld [hSpriteOffset], a
|
ld a, b
|
||||||
ld a, c
|
|
||||||
swap a
|
swap a
|
||||||
and $f
|
and $f
|
||||||
ld b, a
|
|
||||||
add a
|
add a
|
||||||
add a
|
add a
|
||||||
add a ; 8*tiles is height in bytes
|
|
||||||
ld [hSpriteHeight], a
|
|
||||||
ld a, $7
|
|
||||||
sub b ; 7-h ; skip for vertical center (in tiles, relative to current column)
|
|
||||||
ld b, a
|
|
||||||
ld a, [hSpriteOffset]
|
|
||||||
add b ; 7*((8-w)/2) + 7-h ; combined overall offset (in tiles)
|
|
||||||
add a
|
add a
|
||||||
add a
|
ld [wSpriteWidth], a
|
||||||
add a ; 8*(7*((8-w)/2) + 7-h) ; combined overall offset (in bytes)
|
call ReadNextInputBit
|
||||||
ld [hSpriteOffset], a
|
ld [wSpriteLoadFlags], a ; initialite bit1 to 0 and bit0 to the first input bit
|
||||||
xor a
|
; this will load two chunks of data to sSpriteBuffer1 and sSpriteBuffer2
|
||||||
ld [$4000], a
|
; bit 0 decides in which one the first chunk is placed
|
||||||
ld hl, sSpriteBuffer0
|
; fall through
|
||||||
call ZeroSpriteBuffer ; zero buffer 0
|
|
||||||
ld de, sSpriteBuffer1
|
; uncompresses a chunk from the sprite input data stream (pointed to at wd0da) into sSpriteBuffer1 or sSpriteBuffer2
|
||||||
ld hl, sSpriteBuffer0
|
; each chunk is a 1bpp sprite. A 2bpp sprite consist of two chunks which are merged afterwards
|
||||||
call AlignSpriteDataCentered ; copy and align buffer 1 to 0 (containing the MSB of the 2bpp sprite)
|
; note that this is an endless loop which is terminated during a call to MoveToNextBufferPosition by manipulating the stack
|
||||||
|
UncompressSpriteDataLoop::
|
||||||
ld hl, sSpriteBuffer1
|
ld hl, sSpriteBuffer1
|
||||||
call ZeroSpriteBuffer ; zero buffer 1
|
ld a, [wSpriteLoadFlags]
|
||||||
ld de, sSpriteBuffer2
|
bit 0, a
|
||||||
ld hl, sSpriteBuffer1
|
jr z, .useSpriteBuffer1 ; check which buffer to use
|
||||||
call AlignSpriteDataCentered ; copy and align buffer 2 to 1 (containing the LSB of the 2bpp sprite)
|
ld hl, sSpriteBuffer2
|
||||||
pop de
|
.useSpriteBuffer1
|
||||||
jp InterlaceMergeSpriteBuffers
|
call StoreSpriteOutputPointer
|
||||||
|
ld a, [wSpriteLoadFlags]
|
||||||
; copies and aligns the sprite data properly inside the sprite buffer
|
bit 1, a
|
||||||
; sprite buffers are 7*7 tiles in size, the loaded sprite is centered within this area
|
jr z, .startDecompression ; check if last iteration
|
||||||
AlignSpriteDataCentered::
|
call ReadNextInputBit ; if last chunk, read 1-2 bit unpacking mode
|
||||||
ld a, [hSpriteOffset]
|
and a
|
||||||
ld b, $0
|
jr z, .unpackingMode0 ; 0 -> mode 0
|
||||||
|
call ReadNextInputBit ; 1 0 -> mode 1
|
||||||
|
inc a ; 1 1 -> mode 2
|
||||||
|
.unpackingMode0
|
||||||
|
ld [wSpriteUnpackMode], a
|
||||||
|
.startDecompression
|
||||||
|
call ReadNextInputBit
|
||||||
|
and a
|
||||||
|
jr z, .readRLEncodedZeros ; if first bit is 0, the input starts with zeroes, otherwise with (non-zero) input
|
||||||
|
.readNextInput
|
||||||
|
call ReadNextInputBit
|
||||||
ld c, a
|
ld c, a
|
||||||
add hl, bc
|
call ReadNextInputBit
|
||||||
ld a, [hSpriteWidth]
|
sla c
|
||||||
.columnLoop
|
or c ; read next two bits into c
|
||||||
push af
|
and a
|
||||||
push hl
|
jr z, .readRLEncodedZeros ; 00 -> RLEncoded zeroes following
|
||||||
ld a, [hSpriteHeight]
|
call WriteSpriteBitsToBuffer ; otherwise write input to output and repeat
|
||||||
ld c, a
|
call MoveToNextBufferPosition
|
||||||
.columnInnerLoop
|
jr .readNextInput
|
||||||
ld a, [de]
|
.readRLEncodedZeros
|
||||||
inc de
|
ld c, $0 ; number of zeroes it length encoded, the number
|
||||||
ld [hli], a
|
.countConsecutiveOnesLoop ; of consecutive ones determines the number of bits the number has
|
||||||
dec c
|
call ReadNextInputBit
|
||||||
jr nz, .columnInnerLoop
|
and a
|
||||||
pop hl
|
jr z, .countConsecutiveOnesFinished
|
||||||
ld bc, 7*8 ; 7 tiles
|
inc c
|
||||||
add hl, bc ; advance one full column
|
jr .countConsecutiveOnesLoop
|
||||||
pop af
|
.countConsecutiveOnesFinished
|
||||||
dec a
|
ld a, c
|
||||||
jr nz, .columnLoop
|
add a
|
||||||
ret
|
ld hl, LengthEncodingOffsetList
|
||||||
|
add l
|
||||||
; fills the sprite buffer (pointed to in hl) with zeros
|
ld l, a
|
||||||
ZeroSpriteBuffer::
|
jr nc, .noCarry
|
||||||
ld bc, SPRITEBUFFERSIZE
|
inc h
|
||||||
.nextByteLoop
|
.noCarry
|
||||||
xor a
|
ld a, [hli] ; read offset that is added to the number later on
|
||||||
ld [hli], a
|
ld e, a ; adding an offset of 2^length - 1 makes every integer uniquely
|
||||||
dec bc
|
ld d, [hl] ; representable in the length encoding and saves bits
|
||||||
ld a, b
|
|
||||||
or c
|
|
||||||
jr nz, .nextByteLoop
|
|
||||||
ret
|
|
||||||
|
|
||||||
; combines the (7*7 tiles, 1bpp) sprite chunks in buffer 0 and 1 into a 2bpp sprite located in buffer 1 through 2
|
|
||||||
; in the resulting sprite, the rows of the two source sprites are interlaced
|
|
||||||
; de: output address
|
|
||||||
InterlaceMergeSpriteBuffers::
|
|
||||||
xor a
|
|
||||||
ld [$4000], a
|
|
||||||
push de
|
push de
|
||||||
ld hl, sSpriteBuffer2 + (SPRITEBUFFERSIZE - 1) ; destination: end of buffer 2
|
inc c
|
||||||
ld de, sSpriteBuffer1 + (SPRITEBUFFERSIZE - 1) ; source 2: end of buffer 1
|
ld e, $0
|
||||||
ld bc, sSpriteBuffer0 + (SPRITEBUFFERSIZE - 1) ; source 1: end of buffer 0
|
ld d, e
|
||||||
ld a, SPRITEBUFFERSIZE/2 ; $c4
|
.readNumberOfZerosLoop ; reads the next c+1 bits of input
|
||||||
ld [hSpriteInterlaceCounter], a
|
call ReadNextInputBit
|
||||||
.interlaceLoop
|
or e
|
||||||
ld a, [de]
|
ld e, a
|
||||||
|
dec c
|
||||||
|
jr z, .readNumberOfZerosDone
|
||||||
|
sla e
|
||||||
|
rl d
|
||||||
|
jr .readNumberOfZerosLoop
|
||||||
|
.readNumberOfZerosDone
|
||||||
|
pop hl ; add the offset
|
||||||
|
add hl, de
|
||||||
|
ld e, l
|
||||||
|
ld d, h
|
||||||
|
.writeZerosLoop
|
||||||
|
ld b, e
|
||||||
|
xor a ; write 00 to buffer
|
||||||
|
call WriteSpriteBitsToBuffer
|
||||||
|
ld e, b
|
||||||
|
call MoveToNextBufferPosition
|
||||||
dec de
|
dec de
|
||||||
ld [hld], a ; write byte of source 2
|
ld a, d
|
||||||
ld a, [bc]
|
and a
|
||||||
dec bc
|
jr nz, .continueLoop
|
||||||
ld [hld], a ; write byte of source 1
|
ld a, e
|
||||||
ld a, [de]
|
and a
|
||||||
dec de
|
.continueLoop
|
||||||
ld [hld], a ; write byte of source 2
|
jr nz, .writeZerosLoop
|
||||||
ld a, [bc]
|
jr .readNextInput
|
||||||
dec bc
|
|
||||||
ld [hld], a ; write byte of source 1
|
; moves output pointer to next position
|
||||||
ld a, [hSpriteInterlaceCounter]
|
; also cancels the calling function if the all output is done (by removing the return pointer from stack)
|
||||||
|
; and calls postprocessing functions according to the unpack mode
|
||||||
|
MoveToNextBufferPosition::
|
||||||
|
ld a, [wSpriteHeight]
|
||||||
|
ld b, a
|
||||||
|
ld a, [wSpriteCurPosY]
|
||||||
|
inc a
|
||||||
|
cp b
|
||||||
|
jr z, .curColumnDone
|
||||||
|
ld [wSpriteCurPosY], a
|
||||||
|
ld a, [wSpriteOutputPtr]
|
||||||
|
inc a
|
||||||
|
ld [wSpriteOutputPtr], a
|
||||||
|
ret nz
|
||||||
|
ld a, [wSpriteOutputPtr+1]
|
||||||
|
inc a
|
||||||
|
ld [wSpriteOutputPtr+1], a
|
||||||
|
ret
|
||||||
|
.curColumnDone
|
||||||
|
xor a
|
||||||
|
ld [wSpriteCurPosY], a
|
||||||
|
ld a, [wSpriteOutputBitOffset]
|
||||||
|
and a
|
||||||
|
jr z, .bitOffsetsDone
|
||||||
dec a
|
dec a
|
||||||
ld [hSpriteInterlaceCounter], a
|
ld [wSpriteOutputBitOffset], a
|
||||||
jr nz, .interlaceLoop
|
ld hl, wSpriteOutputPtrCached
|
||||||
|
ld a, [hli]
|
||||||
|
ld [wSpriteOutputPtr], a
|
||||||
|
ld a, [hl]
|
||||||
|
ld [wSpriteOutputPtr+1], a
|
||||||
|
ret
|
||||||
|
.bitOffsetsDone
|
||||||
|
ld a, $3
|
||||||
|
ld [wSpriteOutputBitOffset], a
|
||||||
|
ld a, [wSpriteCurPosX]
|
||||||
|
add $8
|
||||||
|
ld [wSpriteCurPosX], a
|
||||||
|
ld b, a
|
||||||
|
ld a, [wSpriteWidth]
|
||||||
|
cp b
|
||||||
|
jr z, .allColumnsDone
|
||||||
|
ld a, [wSpriteOutputPtr]
|
||||||
|
ld l, a
|
||||||
|
ld a, [wSpriteOutputPtr+1]
|
||||||
|
ld h, a
|
||||||
|
inc hl
|
||||||
|
jp StoreSpriteOutputPointer
|
||||||
|
.allColumnsDone
|
||||||
|
pop hl
|
||||||
|
xor a
|
||||||
|
ld [wSpriteCurPosX], a
|
||||||
|
ld a, [wSpriteLoadFlags]
|
||||||
|
bit 1, a
|
||||||
|
jr nz, .done ; test if there is one more sprite to go
|
||||||
|
xor $1
|
||||||
|
set 1, a
|
||||||
|
ld [wSpriteLoadFlags], a
|
||||||
|
jp UncompressSpriteDataLoop
|
||||||
|
.done
|
||||||
|
jp UnpackSprite
|
||||||
|
|
||||||
|
; writes 2 bits (from a) to the output buffer (pointed to from wSpriteOutputPtr)
|
||||||
|
WriteSpriteBitsToBuffer::
|
||||||
|
ld e, a
|
||||||
|
ld a, [wSpriteOutputBitOffset]
|
||||||
|
and a
|
||||||
|
jr z, .offset0
|
||||||
|
cp $2
|
||||||
|
jr c, .offset1
|
||||||
|
jr z, .offset2
|
||||||
|
rrc e ; offset 3
|
||||||
|
rrc e
|
||||||
|
jr .offset0
|
||||||
|
.offset1
|
||||||
|
sla e
|
||||||
|
sla e
|
||||||
|
jr .offset0
|
||||||
|
.offset2
|
||||||
|
swap e
|
||||||
|
.offset0
|
||||||
|
ld a, [wSpriteOutputPtr]
|
||||||
|
ld l, a
|
||||||
|
ld a, [wSpriteOutputPtr+1]
|
||||||
|
ld h, a
|
||||||
|
ld a, [hl]
|
||||||
|
or e
|
||||||
|
ld [hl], a
|
||||||
|
ret
|
||||||
|
|
||||||
|
; reads next bit from input stream and returns it in a
|
||||||
|
ReadNextInputBit::
|
||||||
|
ld a, [wSpriteInputBitCounter]
|
||||||
|
dec a
|
||||||
|
jr nz, .curByteHasMoreBitsToRead
|
||||||
|
call ReadNextInputByte
|
||||||
|
ld [wSpriteInputCurByte], a
|
||||||
|
ld a, $8
|
||||||
|
.curByteHasMoreBitsToRead
|
||||||
|
ld [wSpriteInputBitCounter], a
|
||||||
|
ld a, [wSpriteInputCurByte]
|
||||||
|
rlca
|
||||||
|
ld [wSpriteInputCurByte], a
|
||||||
|
and $1
|
||||||
|
ret
|
||||||
|
|
||||||
|
; reads next byte from input stream and returns it in a
|
||||||
|
ReadNextInputByte::
|
||||||
|
ld a, [wSpriteInputPtr]
|
||||||
|
ld l, a
|
||||||
|
ld a, [wSpriteInputPtr+1]
|
||||||
|
ld h, a
|
||||||
|
ld a, [hli]
|
||||||
|
ld b, a
|
||||||
|
ld a, l
|
||||||
|
ld [wSpriteInputPtr], a
|
||||||
|
ld a, h
|
||||||
|
ld [wSpriteInputPtr+1], a
|
||||||
|
ld a, b
|
||||||
|
ret
|
||||||
|
|
||||||
|
; the nth item is 2^n - 1
|
||||||
|
LengthEncodingOffsetList::
|
||||||
|
dw %0000000000000001
|
||||||
|
dw %0000000000000011
|
||||||
|
dw %0000000000000111
|
||||||
|
dw %0000000000001111
|
||||||
|
dw %0000000000011111
|
||||||
|
dw %0000000000111111
|
||||||
|
dw %0000000001111111
|
||||||
|
dw %0000000011111111
|
||||||
|
dw %0000000111111111
|
||||||
|
dw %0000001111111111
|
||||||
|
dw %0000011111111111
|
||||||
|
dw %0000111111111111
|
||||||
|
dw %0001111111111111
|
||||||
|
dw %0011111111111111
|
||||||
|
dw %0111111111111111
|
||||||
|
dw %1111111111111111
|
||||||
|
|
||||||
|
; unpacks the sprite data depending on the unpack mode
|
||||||
|
UnpackSprite::
|
||||||
|
ld a, [wSpriteUnpackMode]
|
||||||
|
cp $2
|
||||||
|
jp z, UnpackSpriteMode2
|
||||||
|
and a
|
||||||
|
jp nz, XorSpriteChunks
|
||||||
|
ld hl, sSpriteBuffer1
|
||||||
|
call SpriteDifferentialDecode
|
||||||
|
ld hl, sSpriteBuffer2
|
||||||
|
; fall through
|
||||||
|
|
||||||
|
; decodes differential encoded sprite data
|
||||||
|
; input bit value 0 preserves the current bit value and input bit value 1 toggles it (starting from initial value 0).
|
||||||
|
SpriteDifferentialDecode::
|
||||||
|
xor a
|
||||||
|
ld [wSpriteCurPosX], a
|
||||||
|
ld [wSpriteCurPosY], a
|
||||||
|
call StoreSpriteOutputPointer
|
||||||
ld a, [wSpriteFlipped]
|
ld a, [wSpriteFlipped]
|
||||||
and a
|
and a
|
||||||
jr z, .notFlipped
|
jr z, .notFlipped
|
||||||
ld bc, 2*SPRITEBUFFERSIZE
|
ld hl, DecodeNybble0TableFlipped
|
||||||
ld hl, sSpriteBuffer1
|
ld de, DecodeNybble1TableFlipped
|
||||||
.swapLoop
|
jr .storeDecodeTablesPointers
|
||||||
swap [hl] ; if flipped swap nybbles in all bytes
|
|
||||||
inc hl
|
|
||||||
dec bc
|
|
||||||
ld a, b
|
|
||||||
or c
|
|
||||||
jr nz, .swapLoop
|
|
||||||
.notFlipped
|
.notFlipped
|
||||||
pop hl
|
ld hl, DecodeNybble0Table
|
||||||
ld de, sSpriteBuffer1
|
ld de, DecodeNybble1Table
|
||||||
ld c, (2*SPRITEBUFFERSIZE)/16 ; $31, number of 16 byte chunks to be copied
|
.storeDecodeTablesPointers
|
||||||
ld a, [hLoadedROMBank]
|
ld a, l
|
||||||
|
ld [wSpriteDecodeTable0Ptr], a
|
||||||
|
ld a, h
|
||||||
|
ld [wSpriteDecodeTable0Ptr+1], a
|
||||||
|
ld a, e
|
||||||
|
ld [wSpriteDecodeTable1Ptr], a
|
||||||
|
ld a, d
|
||||||
|
ld [wSpriteDecodeTable1Ptr+1], a
|
||||||
|
ld e, $0 ; last decoded nybble, initialized to 0
|
||||||
|
.decodeNextByteLoop
|
||||||
|
ld a, [wSpriteOutputPtr]
|
||||||
|
ld l, a
|
||||||
|
ld a, [wSpriteOutputPtr+1]
|
||||||
|
ld h, a
|
||||||
|
ld a, [hl]
|
||||||
ld b, a
|
ld b, a
|
||||||
jp CopyVideoData
|
swap a
|
||||||
|
and $f
|
||||||
|
call DifferentialDecodeNybble ; decode high nybble
|
||||||
|
swap a
|
||||||
|
ld d, a
|
||||||
|
ld a, b
|
||||||
|
and $f
|
||||||
|
call DifferentialDecodeNybble ; decode low nybble
|
||||||
|
or d
|
||||||
|
ld b, a
|
||||||
|
ld a, [wSpriteOutputPtr]
|
||||||
|
ld l, a
|
||||||
|
ld a, [wSpriteOutputPtr+1]
|
||||||
|
ld h, a
|
||||||
|
ld a, b
|
||||||
|
ld [hl], a ; write back decoded data
|
||||||
|
ld a, [wSpriteHeight]
|
||||||
|
add l ; move on to next column
|
||||||
|
jr nc, .noCarry
|
||||||
|
inc h
|
||||||
|
.noCarry
|
||||||
|
ld [wSpriteOutputPtr], a
|
||||||
|
ld a, h
|
||||||
|
ld [wSpriteOutputPtr+1], a
|
||||||
|
ld a, [wSpriteCurPosX]
|
||||||
|
add $8
|
||||||
|
ld [wSpriteCurPosX], a
|
||||||
|
ld b, a
|
||||||
|
ld a, [wSpriteWidth]
|
||||||
|
cp b
|
||||||
|
jr nz, .decodeNextByteLoop ; test if current row is done
|
||||||
|
xor a
|
||||||
|
ld e, a
|
||||||
|
ld [wSpriteCurPosX], a
|
||||||
|
ld a, [wSpriteCurPosY] ; move on to next row
|
||||||
|
inc a
|
||||||
|
ld [wSpriteCurPosY], a
|
||||||
|
ld b, a
|
||||||
|
ld a, [wSpriteHeight]
|
||||||
|
cp b
|
||||||
|
jr z, .done ; test if all rows finished
|
||||||
|
ld a, [wSpriteOutputPtrCached]
|
||||||
|
ld l, a
|
||||||
|
ld a, [wSpriteOutputPtrCached+1]
|
||||||
|
ld h, a
|
||||||
|
inc hl
|
||||||
|
call StoreSpriteOutputPointer
|
||||||
|
jr .decodeNextByteLoop
|
||||||
|
.done
|
||||||
|
xor a
|
||||||
|
ld [wSpriteCurPosY], a
|
||||||
|
ret
|
||||||
|
|
||||||
|
; decodes the nybble stored in a. Last decoded data is assumed to be in e (needed to determine if initial value is 0 or 1)
|
||||||
|
DifferentialDecodeNybble::
|
||||||
|
srl a ; c=a%2, a/=2
|
||||||
|
ld c, $0
|
||||||
|
jr nc, .evenNumber
|
||||||
|
ld c, $1
|
||||||
|
.evenNumber
|
||||||
|
ld l, a
|
||||||
|
ld a, [wSpriteFlipped]
|
||||||
|
and a
|
||||||
|
jr z, .notFlipped ; determine if initial value is 0 or one
|
||||||
|
bit 3, e ; if flipped, consider MSB of last data
|
||||||
|
jr .selectLookupTable
|
||||||
|
.notFlipped
|
||||||
|
bit 0, e ; else consider LSB
|
||||||
|
.selectLookupTable
|
||||||
|
ld e, l
|
||||||
|
jr nz, .initialValue1 ; load the appropriate table
|
||||||
|
ld a, [wSpriteDecodeTable0Ptr]
|
||||||
|
ld l, a
|
||||||
|
ld a, [wSpriteDecodeTable0Ptr+1]
|
||||||
|
jr .tableLookup
|
||||||
|
.initialValue1
|
||||||
|
ld a, [wSpriteDecodeTable1Ptr]
|
||||||
|
ld l, a
|
||||||
|
ld a, [wSpriteDecodeTable1Ptr+1]
|
||||||
|
.tableLookup
|
||||||
|
ld h, a
|
||||||
|
ld a, e
|
||||||
|
add l
|
||||||
|
ld l, a
|
||||||
|
jr nc, .noCarry
|
||||||
|
inc h
|
||||||
|
.noCarry
|
||||||
|
ld a, [hl]
|
||||||
|
bit 0, c
|
||||||
|
jr nz, .selectLowNybble
|
||||||
|
swap a ; select high nybble
|
||||||
|
.selectLowNybble
|
||||||
|
and $f
|
||||||
|
ld e, a ; update last decoded data
|
||||||
|
ret
|
||||||
|
|
||||||
|
DecodeNybble0Table::
|
||||||
|
dn $0, $1
|
||||||
|
dn $3, $2
|
||||||
|
dn $7, $6
|
||||||
|
dn $4, $5
|
||||||
|
dn $f, $e
|
||||||
|
dn $c, $d
|
||||||
|
dn $8, $9
|
||||||
|
dn $b, $a
|
||||||
|
DecodeNybble1Table::
|
||||||
|
dn $f, $e
|
||||||
|
dn $c, $d
|
||||||
|
dn $8, $9
|
||||||
|
dn $b, $a
|
||||||
|
dn $0, $1
|
||||||
|
dn $3, $2
|
||||||
|
dn $7, $6
|
||||||
|
dn $4, $5
|
||||||
|
DecodeNybble0TableFlipped::
|
||||||
|
dn $0, $8
|
||||||
|
dn $c, $4
|
||||||
|
dn $e, $6
|
||||||
|
dn $2, $a
|
||||||
|
dn $f, $7
|
||||||
|
dn $3, $b
|
||||||
|
dn $1, $9
|
||||||
|
dn $d, $5
|
||||||
|
DecodeNybble1TableFlipped::
|
||||||
|
dn $f, $7
|
||||||
|
dn $3, $b
|
||||||
|
dn $1, $9
|
||||||
|
dn $d, $5
|
||||||
|
dn $0, $8
|
||||||
|
dn $c, $4
|
||||||
|
dn $e, $6
|
||||||
|
dn $2, $a
|
||||||
|
|
||||||
|
; combines the two loaded chunks with xor (the chunk loaded second is the destination). The source chunk is differeintial decoded beforehand.
|
||||||
|
XorSpriteChunks::
|
||||||
|
xor a
|
||||||
|
ld [wSpriteCurPosX], a
|
||||||
|
ld [wSpriteCurPosY], a
|
||||||
|
call ResetSpriteBufferPointers
|
||||||
|
ld a, [wSpriteOutputPtr] ; points to buffer 1 or 2, depending on flags
|
||||||
|
ld l, a
|
||||||
|
ld a, [wSpriteOutputPtr+1]
|
||||||
|
ld h, a
|
||||||
|
call SpriteDifferentialDecode ; decode buffer 1 or 2, depending on flags
|
||||||
|
call ResetSpriteBufferPointers
|
||||||
|
ld a, [wSpriteOutputPtr] ; source buffer, points to buffer 1 or 2, depending on flags
|
||||||
|
ld l, a
|
||||||
|
ld a, [wSpriteOutputPtr+1]
|
||||||
|
ld h, a
|
||||||
|
ld a, [wSpriteOutputPtrCached] ; destination buffer, points to buffer 2 or 1, depending on flags
|
||||||
|
ld e, a
|
||||||
|
ld a, [wSpriteOutputPtrCached+1]
|
||||||
|
ld d, a
|
||||||
|
.xorChunksLoop
|
||||||
|
ld a, [wSpriteFlipped]
|
||||||
|
and a
|
||||||
|
jr z, .notFlipped
|
||||||
|
push de
|
||||||
|
ld a, [de]
|
||||||
|
ld b, a
|
||||||
|
swap a
|
||||||
|
and $f
|
||||||
|
call ReverseNybble ; if flipped reverse the nybbles in the destination buffer
|
||||||
|
swap a
|
||||||
|
ld c, a
|
||||||
|
ld a, b
|
||||||
|
and $f
|
||||||
|
call ReverseNybble
|
||||||
|
or c
|
||||||
|
pop de
|
||||||
|
ld [de], a
|
||||||
|
.notFlipped
|
||||||
|
ld a, [hli]
|
||||||
|
ld b, a
|
||||||
|
ld a, [de]
|
||||||
|
xor b
|
||||||
|
ld [de], a
|
||||||
|
inc de
|
||||||
|
ld a, [wSpriteCurPosY]
|
||||||
|
inc a
|
||||||
|
ld [wSpriteCurPosY], a ; go to next row
|
||||||
|
ld b, a
|
||||||
|
ld a, [wSpriteHeight]
|
||||||
|
cp b
|
||||||
|
jr nz, .xorChunksLoop ; test if column finished
|
||||||
|
xor a
|
||||||
|
ld [wSpriteCurPosY], a
|
||||||
|
ld a, [wSpriteCurPosX]
|
||||||
|
add $8
|
||||||
|
ld [wSpriteCurPosX], a ; go to next column
|
||||||
|
ld b, a
|
||||||
|
ld a, [wSpriteWidth]
|
||||||
|
cp b
|
||||||
|
jr nz, .xorChunksLoop ; test if all columns finished
|
||||||
|
xor a
|
||||||
|
ld [wSpriteCurPosX], a
|
||||||
|
ret
|
||||||
|
|
||||||
|
; reverses the bits in the nybble given in register a
|
||||||
|
ReverseNybble::
|
||||||
|
ld de, NybbleReverseTable
|
||||||
|
add e
|
||||||
|
ld e, a
|
||||||
|
jr nc, .noCarry
|
||||||
|
inc d
|
||||||
|
.noCarry
|
||||||
|
ld a, [de]
|
||||||
|
ret
|
||||||
|
|
||||||
|
; resets sprite buffer pointers to buffer 1 and 2, depending on wSpriteLoadFlags
|
||||||
|
ResetSpriteBufferPointers::
|
||||||
|
ld a, [wSpriteLoadFlags]
|
||||||
|
bit 0, a
|
||||||
|
jr nz, .buffer2Selected
|
||||||
|
ld de, sSpriteBuffer1
|
||||||
|
ld hl, sSpriteBuffer2
|
||||||
|
jr .storeBufferPointers
|
||||||
|
.buffer2Selected
|
||||||
|
ld de, sSpriteBuffer2
|
||||||
|
ld hl, sSpriteBuffer1
|
||||||
|
.storeBufferPointers
|
||||||
|
ld a, l
|
||||||
|
ld [wSpriteOutputPtr], a
|
||||||
|
ld a, h
|
||||||
|
ld [wSpriteOutputPtr+1], a
|
||||||
|
ld a, e
|
||||||
|
ld [wSpriteOutputPtrCached], a
|
||||||
|
ld a, d
|
||||||
|
ld [wSpriteOutputPtrCached+1], a
|
||||||
|
ret
|
||||||
|
|
||||||
|
; maps each nybble to its reverse
|
||||||
|
NybbleReverseTable::
|
||||||
|
db $0, $8, $4, $c, $2, $a, $6 ,$e, $1, $9, $5, $d, $3, $b, $7 ,$f
|
||||||
|
|
||||||
|
; combines the two loaded chunks with xor (the chunk loaded second is the destination). Both chunks are differeintial decoded beforehand.
|
||||||
|
UnpackSpriteMode2::
|
||||||
|
call ResetSpriteBufferPointers
|
||||||
|
ld a, [wSpriteFlipped]
|
||||||
|
push af
|
||||||
|
xor a
|
||||||
|
ld [wSpriteFlipped], a ; temporarily clear flipped flag for decoding the destination chunk
|
||||||
|
ld a, [wSpriteOutputPtrCached]
|
||||||
|
ld l, a
|
||||||
|
ld a, [wSpriteOutputPtrCached+1]
|
||||||
|
ld h, a
|
||||||
|
call SpriteDifferentialDecode
|
||||||
|
call ResetSpriteBufferPointers
|
||||||
|
pop af
|
||||||
|
ld [wSpriteFlipped], a
|
||||||
|
jp XorSpriteChunks
|
||||||
|
|
||||||
|
; stores hl into the output pointers
|
||||||
|
StoreSpriteOutputPointer::
|
||||||
|
ld a, l
|
||||||
|
ld [wSpriteOutputPtr], a
|
||||||
|
ld [wSpriteOutputPtrCached], a
|
||||||
|
ld a, h
|
||||||
|
ld [wSpriteOutputPtr+1], a
|
||||||
|
ld [wSpriteOutputPtrCached+1], a
|
||||||
|
ret
|
||||||
|
|
|
||||||
Loading…
Reference in a new issue