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shave some bytes

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This commit is contained in:
4am 2020-09-07 16:56:40 -04:00
parent 3b0149f9e9
commit a249b986e9
3 changed files with 24 additions and 28 deletions
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8
src/fx/fx.hgr.1bit.fizzle.a
View File

@ -10,11 +10,10 @@ copymasks = $6200 ; [256 bytes, page-aligned]
ldx #(end-start) ; copy LFSR code to zero page
- lda start-1, x
sta $0, x
sta $FF, x
dex
bne -
lda #%00000001 ; create copymask lookup table
-- ldy #$20
-- ldy #$20 ; create copymask table
ora #%10000000
- sta copymasks, x
inx
@ -37,8 +36,9 @@ copymasks = $6200 ; [256 bytes, page-aligned]
rts ; exit via LFSR code on zero page
start
!pseudopc 1 {
!pseudopc 0 {
; in: X,Y=0
!byte %00000001
loop txa
loop1 eor #$B4 ; LFSR form 0xB400 with period 65535
tax ; X is LFSR high byte, Y is LFSR low byte

10
src/fx/fx.hgr.2bit.fizzle.a
View File

@ -10,11 +10,10 @@ copymasks = $6200 ; [128 bytes, should not cross page boundar
ldx #(end-start) ; copy LFSR code to zero page
- lda start-1, x
sta $0, x
sta $FF, x
dex
bne -
lda #%00000011 ; create copymask lookup table
-- ldy #$20
-- ldy #$20 ; create copymask table
ora #%10000000
- sta copymasks, x
inx
@ -25,7 +24,7 @@ copymasks = $6200 ; [128 bytes, should not cross page boundar
bne --
pha
pha
tax ; X=0
tax
clc
-- ldy #$20 ; create address lookup table
tya
@ -39,8 +38,9 @@ copymasks = $6200 ; [128 bytes, should not cross page boundar
rts ; exit via LFSR code on zero page
start
!pseudopc 1 {
!pseudopc 0 {
; in: X,Y=0
!byte %00000011
loop txa
loop1 eor #$60 ; LFSR form 0x6000 with period 32767
tax ; X is LFSR high byte, Y is LFSR low byte

34
src/fx/fx.hgr.checkerboard.fizzle.a
View File

@ -33,7 +33,6 @@ shapemask = $8000 ; [$2000 bytes, page-aligned]
inx
cpx #$C0
bne -
ldx #0 ; create shapemask table
-- lda hgrlo, x
sta $FE
@ -71,26 +70,12 @@ shapemask = $8000 ; [$2000 bytes, page-aligned]
inx
cpx #$C0
bne --
ldx #(end-start) ; copy LFSR code to zero page
- lda start-1, x
sta $0, x
sta $FF, x
dex
bne -
clc ; create shapemaskaddrs lookup table
-- ldy #$20
lda #>shapemask
- sta shapemaskaddrs, x
adc #1
inx
dey
bne -
txa
bne --
lda #%00000011 ; create copymask lookup table
-- ldy #$20
-- ldy #$20 ; create copymask lookup table
ora #%10000000
- sta copymasks, x
inx
@ -99,11 +84,21 @@ shapemask = $8000 ; [$2000 bytes, page-aligned]
asl
asl
bne --
tax ; X=0
tax
clc
-- ldy #$20 ; create address lookup table
tya
- sta addrs, x
adc #1
inx
dey
bne -
txa
bne --
clc ; create shapemaskaddrs lookup table
-- ldy #$20
lda #>shapemask
- sta shapemaskaddrs, x
adc #1
inx
dey
@ -118,8 +113,9 @@ shapemask = $8000 ; [$2000 bytes, page-aligned]
jmp $1
start
!pseudopc 1 {
!pseudopc 0 {
; in: X,Y=0
!byte %00000011
loop txa
loop1 eor #$60 ; LFSR form 0x6000 with period 32767
tax ; X is LFSR high byte, Y is LFSR low byte