mirror of https://github.com/a2-4am/4cade.git
132 lines
3.4 KiB
Plaintext
Executable File
132 lines
3.4 KiB
Plaintext
Executable File
;license:MIT
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;(c) 2019-2020 by 4am/qkumba
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;
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; randomized fade-to-black routine customized for a specific piece of cover art
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; with 75 fill rectangles
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;
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!cpu 6502
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!to "build/COVERFADE",plain
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*=$6000
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!source "src/fx/macros.a"
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+READ_ROM_NO_WRITE
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;init RNG
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lda $C050
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and #$7F
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bne +
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lda #$01
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+ sta @rnd+1
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sta @exit+1
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lda #$20
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sta $e6
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;iterate
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@loop ldy @rnd+1
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tya
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lsr
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bcc +
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;feedback polynomial forms #$41 for period of 127
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eor #$41
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+ sta @rnd+1
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cpy #75+1
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bcs +
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lda width - 1, y
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sta $fd
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lda height - 1, y
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sta $fe
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lda startx - 1, y
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sta $ff
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lda starty - 1, y
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-- pha
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ldx #0
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ldy #0
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jsr $f411 ;hposn
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lda #0
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ldx $fd
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ldy $ff
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- sta ($26), y
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iny
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dex
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bne -
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pla
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clc
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adc #1
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dec $fe
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bne --
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lda #80
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sec
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@wait1 pha
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@wait2 sbc #1
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bne @wait2
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pla
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sbc #1
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bne @wait1
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+
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@rnd lda #0
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@exit cmp #1
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bne @loop
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+READ_RAM1_WRITE_RAM1
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rts
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width
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!byte 02, 03, 03, 05, 03, 03, 03, 03
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!byte 03, 03, 03, 03, 04, 04, 03, 02
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!byte 03, 03, 04, 07, 03, 02, 03, 03
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!byte 03, 03, 03, 03, 03, 03, 03, 03
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!byte 02, 03, 07, 04, 05, 03, 05, 05
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!byte 03, 04, 06, 07, 04, 03, 03, 03
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!byte 03, 02, 04, 05, 03, 03, 04, 06
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!byte 03, 02, 04, 06, 03, 03, 03, 03
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!byte 04, 03, 02, 03, 02, 03, 03, 03
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!byte 03, 03, 02
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height
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!byte 12, 16, 26, 13, 15, 09, 24, 18
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!byte 11, 23, 17, 15, 13, 20, 22, 13
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!byte 16, 12, 21, 18, 10, 15, 10, 21
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!byte 17, 12, 12, 12, 17, 12, 08, 26
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!byte 18, 13, 44, 23, 21, 19, 17, 30
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!byte 11, 10, 25, 18, 07, 14, 13, 15
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!byte 11, 12, 28, 16, 15, 17, 35, 17
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!byte 07, 13, 12, 06, 11, 12, 19, 15
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!byte 11, 08, 13, 07, 16, 12, 24, 16
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!byte 23, 22, 11
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startx
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!byte 000, 000, 001, 000, 000, 000, 000, 002
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!byte 003, 001, 004, 003, 003, 003, 006, 007
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!byte 005, 006, 006, 007, 008, 009, 008, 009
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!byte 010, 011, 011, 012, 012, 012, 013, 014
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!byte 015, 015, 014, 016, 017, 018, 017, 018
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!byte 020, 020, 021, 021, 022, 022, 024, 025
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!byte 024, 026, 027, 026, 028, 029, 028, 027
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!byte 030, 031, 031, 032, 034, 033, 033, 033
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!byte 032, 033, 034, 035, 036, 037, 037, 037
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!byte 037, 037, 038
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starty
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!byte 000, 016, 042, 076, 103, 153, 167, 003
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!byte 027, 123, 049, 098, 152, 172, 008, 036
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!byte 139, 119, 071, 154, 101, 131, 181, 009
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!byte 040, 070, 115, 134, 091, 177, 008, 030
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!byte 068, 109, 128, 169, 003, 031, 058, 091
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!byte 150, 179, 117, 072, 025, 046, 002, 151
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!byte 178, 095, 008, 046, 069, 094, 118, 173
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!byte 040, 018, 058, 003, 015, 034, 079, 106
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!byte 147, 163, 178, 133, 051, 178, 148, 106
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!byte 073, 022, 000
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