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Pointers working for the NMI OAM copy, thanks Ophis

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This commit is contained in:
Andrew Kesterson
2012-11-04 12:25:10 -05:00
parent ff7579cdfe
commit 7ea451361a
2 changed files with 24 additions and 16 deletions
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3
defines.S
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@@ -1 +1,2 @@
.alias curSpriteData curSpriteDataHi
.alias curSpriteDataRead curSpriteDataLo
.alias curSpriteDataWrite curSpriteDataHi

37
nesgame.S
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@@ -199,34 +199,41 @@ _MAIN_loop:
NMI:
LDX #$0
LDY #$0
;; This is almost a reusable function ... store 'sprMario' as our
;; current sprite that we're about to draw
LDA sprMario
STA curSpriteLen
LDA #>sprMarioData
STA curSpriteDataHi
LDA #<sprMarioData
STA curSpriteDataLo
;; ----
_NMI_CopyMarioToOAM:
LDA playery ; set Y position
CLC
ADC sprMarioData, x
STA $0200, x
INX
LDA sprMarioData, x ; set tile number
STA $0200, x
INX
ADC (curSpriteDataLo), y
STA $0200, y
INY
LDA (curSpriteDataLo), y ; set tile number
STA $0200, y
INY
LDA pad1a
AND #%00000001
BNE _NMI_CopyMarioToOAM_padup
LDA sprMarioData, x
LDA (curSpriteDataLo), y
JMP _NMI_CopyMarioToOAM_paddone
_NMI_CopyMarioToOAM_padup:
LDA sprMarioData, x ; set attributes
LDA sprMarioData, y ; set attributes
_NMI_CopyMarioToOAM_paddone:
STA $0200, x
INX
STA $0200, y
INY
LDA playerx ; set X position
CLC
ADC sprMarioData, x
STA $0200, x
INX
INY ; increment the sprite counter
CPY curSpriteLen ; any more sprites in the current multisprite?
ADC (curSpriteDataLo), y
STA $0200, y
INY
INX ; increment the sprite counter
CPX curSpriteLen ; any more sprites in the current multisprite?
BNE _NMI_CopyMarioToOAM
;; We need to copy all our OAM data to put sprites on screen during