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| author | Juan J. Martinez <jjm@usebox.net> | 2021-05-03 08:21:10 +0100 |
|---|---|---|
| committer | Juan J. Martinez <jjm@usebox.net> | 2021-05-03 10:00:00 +0100 |
| commit | c3b0fa04a663fe233765b83d3be41a42aa08c25d (patch) | |
| tree | 0befda349001ef6ce306b39378f9c70ad917363e /lib/cpcrslib/cpc_UnExoOpt.s | |
| download | return-of-traxtor-cpc-c3b0fa04a663fe233765b83d3be41a42aa08c25d.tar.gz return-of-traxtor-cpc-c3b0fa04a663fe233765b83d3be41a42aa08c25d.zip | |
Diffstat (limited to 'lib/cpcrslib/cpc_UnExoOpt.s')
| -rw-r--r-- | lib/cpcrslib/cpc_UnExoOpt.s | 183 |
1 files changed, 183 insertions, 0 deletions
diff --git a/lib/cpcrslib/cpc_UnExoOpt.s b/lib/cpcrslib/cpc_UnExoOpt.s new file mode 100644 index 0000000..14197cc --- /dev/null +++ b/lib/cpcrslib/cpc_UnExoOpt.s @@ -0,0 +1,183 @@ +; ******************************************************
+; ** Librería de rutinas SDCC para Amstrad CPC **
+; ** Raúl Simarro (Artaburu) - 2009, 2012 **
+; ******************************************************
+
+
+;*************************************
+; UNEXO
+;*************************************
+
+
+; Exomizer 2 Z80 decoder
+; by Metalbrain
+;
+; optimized by Antonio Villena
+;
+; compression algorithm by Magnus Lind
+
+;input: hl=compressed data start
+; de=uncompressed destination start
+;
+; you may change exo_mapbasebits to point to any free buffer
+
+
+.globl _cpc_UnExo
+
+_cpc_UnExo::
+
+; POP AF
+; POP HL ;DESTINATION ADDRESS
+; POP DE ;SPRITE DATA
+; PUSH AF
+
+ LD IX,#2
+ ADD IX,SP
+ LD e,2 (IX)
+ LD d,3 (IX) ;DESTINO
+ LD l,0 (IX)
+ LD h,1 (IX) ;TEXTO ORIGEN
+
+ di
+ call deexo
+ ei
+ ret
+
+deexo:
+ ld iy, #exo_mapbasebits
+ ld a,#128
+ ld b,#52
+ push de
+exo_initbits:
+ ex af,af'
+ ld a,b
+ sub #4
+ and #15
+ jr nz,exo_node1
+ ld de,#1 ;DE=b2
+exo_node1:
+ ld c,#16
+ ex af, af'
+exo_get4bits:
+ call exo_getbit
+ rl c
+ jr nc,exo_get4bits
+ ld (iy),c ;bits[i]=b1
+ push hl
+ ld hl,#1
+ .db #210 ;3 bytes nop (JP NC)
+exo_setbit:
+ add hl,hl
+ dec c
+ jr nz,exo_setbit
+ ld 52 (iy),e
+ ld 104 (iy),d ;base[i]=b2
+ add hl,de
+ ex de,hl
+ inc iy
+ pop hl
+ djnz exo_initbits
+ inc c
+exo_literalseq:
+ pop de
+exo_literalcopy:
+ ldir ;copy literal(s)
+exo_mainloop:
+ ld c,#1
+ call exo_getbit ;literal?
+ jr c,exo_literalcopy
+ ld c,#255
+exo_getindex:
+ inc c
+ call exo_getbit
+ jr nc,exo_getindex
+ bit 4,c
+ jr z,exo_continue
+ bit 0, c
+ ret z
+ push de
+ ld d,#16
+ call exo_getbits
+ jr exo_literalseq
+exo_continue:
+ push de
+ call exo_getpair
+ push bc
+ pop ix
+ ld de,#560 ;512+48 ;1?
+ inc b
+ djnz exo_dontgo
+ dec c
+ jr z, exo_goforit
+ dec c ;2?
+exo_dontgo:
+ ld de,#1056 ;1024+32
+ jr z,exo_goforit
+ ld e,#16
+exo_goforit:
+ call exo_getbits
+ ex af, af'
+ ld a,e
+ add a,c
+ ld c,a
+ ex af, af'
+ call exo_getpair ;bc=offset
+ pop de ;de=destination
+ push hl
+ ld h,d
+ ld l,e
+ sbc hl,bc ;hl=origin
+ push ix
+ pop bc ;bc=lenght
+ ldir
+ pop hl ;Keep HL, DE is updated
+ jr exo_mainloop ;Next!
+
+exo_getpair:
+ ld iy,#exo_mapbasebits
+ ld b,#0
+ add iy,bc
+ ld d,(iy)
+ call exo_getbits
+ push hl
+ ld l, 52 (iy)
+ ld h, 104 (iy)
+ add hl, bc ;Always clear C flag
+ ld b, h
+ ld c, l
+ pop hl
+ ret
+
+exo_getbits:
+ ld bc,#0 ;get D bits in BC
+exo_gettingbits:
+ dec d
+ ret m
+ call exo_getbit
+ rl c
+ rl b
+ jr exo_gettingbits
+
+exo_getbit:
+ add a, a ;get one bit
+ ret nz
+ ld a, (hl)
+ inc hl
+ adc a, a
+ ret
+
+exo_mapbasebits:
+ ;defs 156 ;tables for bits, baseL, baseH
+ .db #0,#0,#0,#0,#0,#0,#0,#0,#0,#0,#0,#0
+ .db #0,#0,#0,#0,#0,#0,#0,#0,#0,#0,#0,#0
+ .db #0,#0,#0,#0,#0,#0,#0,#0,#0,#0,#0,#0
+ .db #0,#0,#0,#0,#0,#0,#0,#0,#0,#0,#0,#0
+ .db #0,#0,#0,#0,#0,#0,#0,#0,#0,#0,#0,#0
+ .db #0,#0,#0,#0,#0,#0,#0,#0,#0,#0,#0,#0
+ .db #0,#0,#0,#0,#0,#0,#0,#0,#0,#0,#0,#0
+ .db #0,#0,#0,#0,#0,#0,#0,#0,#0,#0,#0,#0
+ .db #0,#0,#0,#0,#0,#0,#0,#0,#0,#0,#0,#0
+ .db #0,#0,#0,#0,#0,#0,#0,#0,#0,#0,#0,#0
+ .db #0,#0,#0,#0,#0,#0,#0,#0,#0,#0,#0,#0
+ .db #0,#0,#0,#0,#0,#0,#0,#0,#0,#0,#0,#0
+ .db #0,#0,#0,#0,#0,#0,#0,#0,#0,#0,#0,#0
\ No newline at end of file |