mirror of
https://github.com/deater/dos33fsprogs.git
synced 2024-12-25 20:30:31 +00:00
kfest: compress using lz4, now smaller than 2k!!!!!
This commit is contained in:
parent
ddb39a92fa
commit
722cd765be
@ -5,15 +5,28 @@ TOKENIZE = ../asoft_basic-utils/tokenize_asoft
|
||||
|
||||
all: kfest18.dsk
|
||||
|
||||
kfest18.dsk: RASTER
|
||||
kfest18.dsk: RASTER RASTER_C
|
||||
$(DOS33) -y kfest18.dsk BSAVE -a 0x2000 RASTER
|
||||
$(DOS33) -y kfest18.dsk BSAVE -a 0x1000 RASTER_C
|
||||
|
||||
raster.o: raster.s
|
||||
ca65 -o raster.o raster.s -l raster.lst
|
||||
|
||||
RASTER.lz4: RASTER
|
||||
lz4 -f -16 RASTER
|
||||
|
||||
RASTER: raster.o
|
||||
ld65 -o RASTER raster.o -C ../linker_scripts/apple2_2000.inc
|
||||
|
||||
raster_decompress.o: raster_decompress.s RASTER.lz4
|
||||
ca65 -o raster_decompress.o raster_decompress.s
|
||||
|
||||
RASTER_C: raster_decompress.o
|
||||
ld65 -o RASTER_C raster_decompress.o -C ../linker_scripts/apple2_1000.inc
|
||||
|
||||
|
||||
|
||||
|
||||
raster2.o: raster2.s
|
||||
ca65 -o raster2.o raster2.s -l raster2.lst
|
||||
|
||||
@ -22,4 +35,4 @@ RASTER2: raster2.o
|
||||
|
||||
|
||||
clean:
|
||||
rm -f *~ *.o *.lst RASTER RASTER2
|
||||
rm -f *~ *.o *.lst RASTER RASTER2 RASTER.lz4
|
||||
|
@ -1,4 +1,4 @@
|
||||
KFEST18 SUPER RASTEBAR DEMO
|
||||
KFEST18 SUPER RASTERBAR 2K DEMO
|
||||
by deater (Vince Weaver) vince@deater.net
|
||||
|
||||
Written for the Kansasfest Hackfest.
|
||||
|
Binary file not shown.
238
kfest2018/raster_decompress.s
Normal file
238
kfest2018/raster_decompress.s
Normal file
@ -0,0 +1,238 @@
|
||||
; Note: needs some extra work
|
||||
; Set up initial pointer
|
||||
; Skip/strip the LZ4 header
|
||||
|
||||
LZ4_SRC = $00
|
||||
LZ4_DST = $02
|
||||
LZ4_END = $04
|
||||
COUNT = $06
|
||||
DELTA = $08
|
||||
|
||||
|
||||
|
||||
UNPACK_BUFFER = $2000
|
||||
|
||||
|
||||
start:
|
||||
|
||||
; inline lz4_decode
|
||||
|
||||
; LZ4 data decompressor for Apple II
|
||||
|
||||
; Code by Peter Ferrie (qkumba) (peter.ferrie@gmail.com)
|
||||
; "LZ4 unpacker in 143 bytes (6502 version) (2013)"
|
||||
; http://pferrie.host22.com/misc/appleii.htm
|
||||
; This is that code, but with comments and labels added for clarity.
|
||||
; I also found a bug when decoding with runs of multiples of 256
|
||||
; which has since been fixed upstream.
|
||||
|
||||
; For LZ4 reference see
|
||||
; https://github.com/lz4/lz4/wiki/lz4_Frame_format.md
|
||||
|
||||
; LZ4 summary:
|
||||
;
|
||||
; HEADER:
|
||||
; Should: check for magic number 04 22 4d 18
|
||||
; FLG: 64 in our case (01=version, block.index=1, block.checksum=0
|
||||
; size=0, checksum=1, reserved
|
||||
; MAX Blocksize: 40 (64kB)
|
||||
; HEADER CHECKSUM: a7
|
||||
; BLOCK HEADER: 4 bytes (le) If highest bit set, uncompressed!
|
||||
; BLOCKS:
|
||||
; Token byte. High 4-bits literal length, low 4-bits copy length
|
||||
; + If literal length==15, then following byte gets added to length
|
||||
; If that byte was 255, then keep adding bytes until not 255
|
||||
; + The literal bytes follow. There may be zero of them
|
||||
; + Next is block copy info. little-endian 2-byte offset to
|
||||
; be subtracted from current read position indicating source
|
||||
; + The low 4-bits of the token are the copy length, which needs
|
||||
; 4 added to it. As with the literal length, if it is 15 then
|
||||
; you read a byte and add (and if that byte is 255, keep adding)
|
||||
|
||||
|
||||
;======================
|
||||
; LZ4 decode
|
||||
;======================
|
||||
; input buffer in LZ4_SRC
|
||||
; output buffer hardcoded still
|
||||
; size in ENDH:ENDL
|
||||
|
||||
lda #<(data)
|
||||
sta LZ4_SRC
|
||||
lda #>(data)
|
||||
sta LZ4_SRC+1
|
||||
|
||||
lda #<(data_end)
|
||||
sta LZ4_END
|
||||
lda #>(data_end)
|
||||
sta LZ4_END+1
|
||||
|
||||
lz4_decode:
|
||||
|
||||
lda #>UNPACK_BUFFER ; original unpacked data offset
|
||||
sta LZ4_DST+1
|
||||
; lda #<UNPACK_BUFFER
|
||||
; sta LZ4_DST
|
||||
|
||||
unpmain:
|
||||
ldy #0 ; used to index, always zero
|
||||
|
||||
sty LZ4_DST ; we know this will be zero ($4000)
|
||||
|
||||
parsetoken:
|
||||
jsr getsrc ; get next token
|
||||
pha ; save for later (need bottom 4 bits)
|
||||
|
||||
lsr ; number of literals in top 4 bits
|
||||
lsr ; so shift into place
|
||||
lsr
|
||||
lsr
|
||||
beq copymatches ; if zero, then no literals
|
||||
; jump ahead and copy
|
||||
|
||||
jsr buildcount ; add up all the literal sizes
|
||||
; result is in ram[count+1]-1:A
|
||||
tax ; now in ram[count+1]-1:X
|
||||
jsr docopy ; copy the literals
|
||||
|
||||
lda LZ4_SRC ; 16-bit compare
|
||||
cmp LZ4_END ; to see if we have reached the end
|
||||
lda LZ4_SRC+1
|
||||
sbc LZ4_END+1
|
||||
bcs done
|
||||
|
||||
copymatches:
|
||||
jsr getsrc ; get 16-bit delta value
|
||||
sta DELTA
|
||||
jsr getsrc
|
||||
sta DELTA+1
|
||||
|
||||
pla ; restore token
|
||||
and #$0f ; get bottom 4 bits
|
||||
; match count. 0 means 4
|
||||
; 15 means 19+, must be calculated
|
||||
|
||||
jsr buildcount ; add up count bits, in ram[count+1]-:A
|
||||
|
||||
clc
|
||||
adc #4 ; adjust count by 4 (minmatch)
|
||||
|
||||
tax ; now in ramp[count+1]-1:X
|
||||
|
||||
beq copy_no_adjust ; BUGFIX, don't increment if
|
||||
; exactly a multiple of 0x100
|
||||
bcc copy_no_adjust
|
||||
|
||||
inc COUNT+1 ; increment if we overflowed
|
||||
copy_no_adjust:
|
||||
|
||||
lda LZ4_SRC+1 ; save src on stack
|
||||
pha
|
||||
lda LZ4_SRC
|
||||
pha
|
||||
|
||||
sec ; subtract delta
|
||||
lda LZ4_DST ; from destination, make new src
|
||||
sbc DELTA
|
||||
sta LZ4_SRC
|
||||
lda LZ4_DST+1
|
||||
sbc DELTA+1
|
||||
sta LZ4_SRC+1
|
||||
|
||||
jsr docopy ; do the copy
|
||||
|
||||
pla ; restore the src
|
||||
sta LZ4_SRC
|
||||
pla
|
||||
sta LZ4_SRC+1
|
||||
|
||||
jmp parsetoken ; back to parsing tokens
|
||||
|
||||
done:
|
||||
pla
|
||||
|
||||
|
||||
; in theory could fall through if we loaded the exact right amount
|
||||
|
||||
jmp $2000
|
||||
|
||||
|
||||
;=========
|
||||
; getsrc
|
||||
;=========
|
||||
; gets byte from src into A, increments pointer
|
||||
getsrc:
|
||||
lda (LZ4_SRC), Y ; get a byte from src
|
||||
inc LZ4_SRC ; increment pointer
|
||||
bne done_getsrc ; update 16-bit pointer
|
||||
inc LZ4_SRC+1 ; on 8-bit overflow
|
||||
done_getsrc:
|
||||
rts
|
||||
|
||||
;============
|
||||
; buildcount
|
||||
;============
|
||||
buildcount:
|
||||
ldx #1 ; high count starts at 1
|
||||
stx COUNT+1 ; (loops at zero?)
|
||||
cmp #$0f ; if LITERAL_COUNT < 15, we are done
|
||||
bne done_buildcount
|
||||
buildcount_loop:
|
||||
sta COUNT ; save LITERAL_COUNT (15)
|
||||
jsr getsrc ; get the next byte
|
||||
tax ; put in X
|
||||
clc
|
||||
adc COUNT ; add new byte to old value
|
||||
bcc bc_8bit_oflow ; if overflow, increment high byte
|
||||
inc COUNT+1
|
||||
bc_8bit_oflow:
|
||||
inx ; check if read value was 255
|
||||
beq buildcount_loop ; if it was, keep looping and adding
|
||||
done_buildcount:
|
||||
rts
|
||||
|
||||
;============
|
||||
; getput
|
||||
;============
|
||||
; gets a byte, then puts the byte
|
||||
getput:
|
||||
jsr getsrc
|
||||
; fallthrough to putdst
|
||||
|
||||
;=============
|
||||
; putdst
|
||||
;=============
|
||||
; store A into destination
|
||||
putdst:
|
||||
sta (LZ4_DST), Y ; store A into destination
|
||||
inc LZ4_DST ; increment 16-bit pointer
|
||||
bne putdst_end ; if overflow, increment top byte
|
||||
inc LZ4_DST+1
|
||||
putdst_end:
|
||||
rts
|
||||
|
||||
;=============================
|
||||
; docopy
|
||||
;=============================
|
||||
; copies ram[count+1]-1:X bytes
|
||||
; from src to dst
|
||||
docopy:
|
||||
|
||||
docopy_loop:
|
||||
jsr getput ; get/put byte
|
||||
dex ; decrement count
|
||||
bne docopy_loop ; if not zero, loop
|
||||
dec COUNT+1 ; if zero, decrement high byte
|
||||
bne docopy_loop ; if not zero, loop
|
||||
|
||||
rts
|
||||
|
||||
|
||||
;===============================================
|
||||
; External modules
|
||||
;===============================================
|
||||
|
||||
; Load, skipping 11 bytes of header
|
||||
data:
|
||||
.incbin "RASTER.lz4",11
|
||||
data_end:
|
Loading…
Reference in New Issue
Block a user