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@Cyanne
Created January 13, 2023 03:13
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StoreGun:
; Line order data starting at $20
LDA #$00 ; Gun 1 Blue Laser Upper Row
STA $20
LDA #$60 ; 2 red
STA $21
LDA #$68 ; 3 green
STA $22
LDA #$00 ; 4 blue
STA $23
LDA #$00 ; Gun 1 Blue Laser Upper Row
STA $24
LDA #$60 ; 2 red
STA $25
LDA #$68 ; 3 green
STA $26
LDA #$68 ; 4 green
STA $27
LDA #$00 ; Gun 1 Blue Laser Upper Row
STA $28
LDA #$60 ; 2 red
STA $29
LDA #$68 ; 3 green
STA $2a
LDA #$00 ; 4 blue
STA $2b
LDA #$00 ; Gun 1 Blue Laser Upper Row
STA $2c
LDA #$60 ; 2 red
STA $2d
LDA #$68 ; 3 green
STA $2e
LDA #$60 ; 4 red
STA $2f
LDA #$08 ; Gun 1 Blue Laser Bottom Row
STA $30
LDA #$18 ; 2 red bottom
STA $31
LDA #$70 ; 3 green bottom
STA $32
LDA #$18 ; 4 red bottom
STA $33
LDA #$10 ; Gun 1-4 Body Rows
STA $34
STA $35
STA $36
STA $37
LDA #$10 ; Gun 1-4 Body Rows
STA $38
STA $39
STA $3a
STA $3b
LDA #$10 ; Gun 1-4 Body Rows
STA $3c
STA $3d
STA $3e
STA $3f
LDA #$ff ; Done
STA $40
; Blue Laser Upper Rows ($00-$07)
LDA #$06
STA $01
LDA #$0e
STA $02
LDA #$03
STA $03
LDA #$01
STA $04
LDA #$03
STA $05
LDA #$0e
STA $06
LDA #$06
STA $07
; Blue Laser Bottom Row ($08-$10)
LDA #$06
STA $0a
LDA #$0e
STA $0b
LDA #$01
STA $0c
LDA #$0e
STA $0d
LDA #$06
STA $0e
; Red Laser Upper Rows ($60-$67)
LDA #$02
STA $61
LDA #$08
STA $62
LDA #$07
STA $63
LDA #$01
STA $64
LDA #$07
STA $65
LDA #$08
STA $66
LDA #$02
STA $67
; Red Laser Bottom Row ($18-$1f)
LDA #$02
STA $1a
LDA #$08
STA $1b
LDA #$01
STA $1c
LDA #$08
STA $1d
LDA #$02
STA $1e
; Green Laser Upper Rows ($68-$6f)
LDA #$09
STA $69
LDA #$05
STA $6a
LDA #$0d
STA $6b
LDA #$01
STA $6c
LDA #$0d
STA $6d
LDA #$05
STA $6e
LDA #$09
STA $6f
; Green Laser Upper Rows ($70-$77)
LDA #$09
STA $72
LDA #$05
STA $73
LDA #$01
STA $74
LDA #$05
STA $75
LDA #$09
STA $76
; Gun Body Row ($11-$17)
LDA #$0b
STA $11
LDA #$0b
STA $12
LDA #$0c
STA $13
LDA #$0c
STA $14
LDA #$0f
STA $15
LDA #$0f
STA $16
LDA #$0c
STA $17
DrawGun:
; A: Color
LDX #$00 ; X: Init memory pos reader counter.
LDY #$00 ; Y: Init screen pos writer counter.
LDA #$01 ; | Init address $50: Line order counter.
STA $50 ; |
; Address $51: Backup space for Y
; | Init address $52: Line progress counter
DrawGunLoop:
LDA $00,X ; Read color from address $00+X
STA $0200,Y ; Store this color to address $0200+Y
INX
INC $52
LDA $52
CMP #$09 ; Check if line is done
BEQ AddLine
INY
JMP DrawGunLoop
AddLine:
LDA #$00 ; \ Reset line progress counter
STA $52 ; /
TYA ; \ Backup Y (screen pos counter) into $51
STA $51 ; /
LDY $50 ; Load into Y Line Order Counter ($50)
; Re-set memory read position X by reading the line order data starting at $20
LDA $0020,Y ; Y now being the line order count
CMP #$ff
BEQ Exit
TAX ; Give the resulting reset point to X
INY ; Increment line order counter
STY $50 ; Store it back into $50
LDY $51 ; Recover backup of Y to Y (screen pos counter)
JMP DrawGunLoop
Exit:
BRK
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