164 lines
3.5 KiB
NASM
164 lines
3.5 KiB
NASM
;===========================================================
|
|
; Ice Rod freezes water
|
|
; Written by Conn
|
|
;
|
|
;===========================================================
|
|
|
|
namespace IceRod
|
|
{
|
|
Main:
|
|
{
|
|
lorom
|
|
|
|
org $088a5d ; jsl to main code
|
|
jsl $0efba0
|
|
|
|
|
|
org $0efba0 ; main code
|
|
STA $03E4,x ; load native value
|
|
TAY
|
|
LDA $008C ; check if you're on overworld
|
|
BNE $01
|
|
RTL
|
|
LDA $03A3 ; disable other flying object icing water (boomerang, sword beam)
|
|
CMP #$06
|
|
BEQ $01
|
|
RTL
|
|
CPX #$04 ; check if ice shot #1 only is used (disable 2nd shot to ice)
|
|
BEQ $01
|
|
RTL
|
|
LDA $03E8 ; check if ice shot is on water tiles
|
|
CMP #$08
|
|
BEQ $08
|
|
LDA $03E8 ; check if ice shot is on native unused, edited blocks
|
|
CMP #$03
|
|
BEQ $01
|
|
RTL
|
|
LDA $0303 ; double check if really ice shot is used
|
|
CMP #$06
|
|
BEQ $01
|
|
RTL
|
|
LDA $0304
|
|
CMP #$06
|
|
BEQ $01
|
|
RTL
|
|
TXA
|
|
STA $7ED004 ; store native x value into ram to regain after code
|
|
LDA $4212 ; wait for vblank to enable dma transfer
|
|
AND #$80
|
|
BEQ $F9
|
|
REP #$30
|
|
LDA $2116
|
|
STA $7ED005 ; store native value to regain later
|
|
LDA $00 ; calculation procedure to get correct x,y coordinates for new tile
|
|
SEC
|
|
SBC $0708
|
|
AND $070A
|
|
ASL A
|
|
ASL A
|
|
ASL A
|
|
STA $06
|
|
LDA $02
|
|
SEC
|
|
SBC $070C
|
|
AND $070E
|
|
ORA $06
|
|
TAX
|
|
LDA #$00B7
|
|
STA $7E2000,x ; store new 16x16 ice tile into ram (property of tile!)
|
|
CLC
|
|
STZ $02 ; calculation procedure to get 8x8 vram map address (look of tile)
|
|
TXA
|
|
AND #$003F
|
|
CMP #$0020
|
|
BCC $05
|
|
LDA #$0400
|
|
STA $02
|
|
TXA
|
|
AND #$0FFF
|
|
CMP #$0800
|
|
BCC $07
|
|
LDA $02
|
|
ADC #$07FF
|
|
STA $02
|
|
TXA
|
|
AND #$001F
|
|
ADC $02
|
|
STA $02
|
|
TXA
|
|
AND #$0780
|
|
LSR A
|
|
ADC $02
|
|
STA $2116 ; store vram address for upper tile part (8x16) to $2116
|
|
STA $7ED007
|
|
LDA #$1D83 ; load new ice tiles
|
|
STA $7ED000
|
|
STA $7ED002
|
|
JSR $FD00 ; jsr to dma vram transfer for upper ice tile part
|
|
REP #$30
|
|
LDA $7ED007 ; regain vram address
|
|
ADC #$0020 ; add 20 for lower part (8x16) and store to $2116
|
|
STA $2116
|
|
JSR $FD00 ; jsr to dma vram transfer for lower ice tile part
|
|
LDA $7ED005 ; regain native register value
|
|
STA $2116
|
|
SEP #$30
|
|
LDA $7ED004 ; regain native x-value
|
|
TAX
|
|
RTL
|
|
|
|
|
|
org $0efd00 ; vram dma transfer
|
|
LDA #$007E ; load origin of bytes to transfer (7E/d000)
|
|
STA $4304
|
|
LDA #$D000
|
|
STA $4302
|
|
SEP #$30
|
|
LDA #$18 ; bus
|
|
STA $4301
|
|
LDA #$04 ; transfer 4 bytes
|
|
STA $4305
|
|
LDA #$01
|
|
STA $4300
|
|
STA $420B ; make dma transfer
|
|
RTS
|
|
|
|
|
|
; bug fix to not swim through tiles but jump onto them
|
|
|
|
org $07dc9e
|
|
jsl $0efc80
|
|
nop
|
|
|
|
org $0efc80
|
|
LDA $0A
|
|
TSB $0343
|
|
TSB $0348
|
|
RTL
|
|
|
|
; bug fix to stop gliding on shallow water when leaving ice tile
|
|
|
|
org $07dd1b
|
|
jsl $0efc90
|
|
nop
|
|
|
|
org $0efc90
|
|
LDA $0A
|
|
TSB $0359
|
|
LDA $0350
|
|
CMP #$0100
|
|
BNE $03
|
|
STZ $034A
|
|
RTL
|
|
|
|
|
|
org $0e95dc ; get a 0e written here (first byte) to enable gliding on new tiles
|
|
ASL $5757
|
|
|
|
org $0f85b8 ; get new tile values (83 1d) written 4 times here
|
|
STA $1D,s
|
|
STA $1D,s
|
|
STA $1D,s
|
|
STA $1D,s
|
|
}
|
|
} ; namespace IceRod |