Port the REV01 Background Effects
From Sonic Retro
(Original guide by jman2050)
Looking at the REV01 version of Sonic 1, I can see why it's Rev01. They pretty much completely overhauled the entire BG deformation part of the engine. The drawing system has been changed (and from what I've seen, more similar to the way Sonic 2 does things) and the deformation data for every level has been changed to fit this new code. Also, in every level besides SBZ2, it was used to enhance the deformation effects. To see the difference in your own Sonic 1 ROM hack, you'll have to do the following...
Contents
Steps
Step 1
First, we'll do the easiest change. Go to label Obj0A_WobbleData in Hivebrain's 2005 disassembly and replace the entire block with this: <asm>Obj0A_WobbleData: dc.b 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2 dc.b 2, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 4, 3 dc.b 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 2, 2, 2, 2 dc.b 2, 2, 2, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, -1, -1 dc.b -1, -1, -1, -2, -2, -2, -2, -2, -3, -3, -3, -3, -3 dc.b -3, -3, -4, -4, -4, -4, -4, -4, -4, -4, -4, -4, -4 dc.b -4, -4, -4, -4, -4, -4, -4, -4, -4, -4, -4, -4, -4 dc.b -4, -4, -4, -4, -4, -3, -3, -3, -3, -3, -3, -3, -2 dc.b -2, -2, -2, -2, -1, -1, -1, -1, -1 dc.b 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2 dc.b 2, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 4, 3 dc.b 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 2, 2, 2, 2 dc.b 2, 2, 2, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, -1, -1 dc.b -1, -1, -1, -2, -2, -2, -2, -2, -3, -3, -3, -3, -3 dc.b -3, -3, -4, -4, -4, -4, -4, -4, -4, -4, -4, -4, -4 dc.b -4, -4, -4, -4, -4, -4, -4, -4, -4, -4, -4, -4, -4 dc.b -4, -4, -4, -4, -4, -3, -3, -3, -3, -3, -3, -3, -2 dc.b -2, -2, -2, -2, -1, -1, -1, -1, -1</asm>
The programmers extended this array so it would also be usable by the deformation data even though it was designed to be used by the water bubbles.
Step 2
Next, we'll do the BGScroll data. Go to BGScroll_GHZ in the disassembly. Replace everything from there until the end of BGScroll_End with the following: <asm>BgScroll_GHZ: ; XREF: BgScroll_Index clr.l ($FFFFF708).w clr.l ($FFFFF70C).w clr.l ($FFFFF714).w clr.l ($FFFFF71C).w lea ($FFFFA800).w,a2 clr.l (a2)+ clr.l (a2)+ clr.l (a2)+ rts
- ===========================================================================
BgScroll_LZ: ; XREF: BgScroll_Index asr.l #1,d0 move.w d0,($FFFFF70C).w rts
- ===========================================================================
BgScroll_MZ: ; XREF: BgScroll_Index rts
- ===========================================================================
BgScroll_SLZ: ; XREF: BgScroll_Index asr.l #1,d0 addi.w #$C0,d0 move.w d0,($FFFFF70C).w clr.l ($FFFFF708).w rts
- ===========================================================================
BgScroll_SYZ: ; XREF: BgScroll_Index asl.l #4,d0 move.l d0,d2 asl.l #1,d0 add.l d2,d0 asr.l #8,d0 addq.w #1,d0 move.w d0,($FFFFF70C).w clr.l ($FFFFF708).w rts
- ===========================================================================
BgScroll_SBZ: ; XREF: BgScroll_Index andi.w #$7F8,d0 asr.w #3,d0 addq.w #1,d0 move.w d0,($FFFFF70C).w rts
- ===========================================================================
BgScroll_End: ; XREF: BgScroll_Index move.w ($FFFFF700).w,d0 asr.w #1,d0 move.w d0,($FFFFF708).w move.w d0,($FFFFF710).w asr.w #2,d0 move.w d0,d1 add.w d0,d0 add.w d1,d0 move.w d0,($FFFFF718).w clr.l ($FFFFF70C).w clr.l ($FFFFF714).w clr.l ($FFFFF71C).w lea ($FFFFA800).w,a2 clr.l (a2)+ clr.l (a2)+ clr.l (a2)+ rts </asm>
The starting deformation data for every stage needed to be changed. To be precise, it prevents bugs that occur in the scrolling in SBZ and SYZ, and prevents a bug that causes GHZ's bg not to appear at all.
Step 3
Next, we'll do the deformation data itself. Go to Deform_GHZ, and replace everything from there until the end of Deform_SBZ, straight down (right before ScrollHoriz) with the following: <asm>Deform_GHZ: move.w ($FFFFF73A).w,d4 ext.l d4 asl.l #5,d4 move.l d4,d1 asl.l #1,d4 add.l d1,d4 moveq #0,d6 bsr.w ScrollBlock6 move.w ($FFFFF73A).w,d4 ext.l d4 asl.l #7,d4 moveq #0,d6 bsr.w ScrollBlock5 lea ($FFFFCC00).w,a1 move.w ($FFFFF704).w,d0 andi.w #$7FF,d0 lsr.w #5,d0 neg.w d0 addi.w #$20,d0 ; ' ' bpl.s Deform_GHZ_1 moveq #0,d0
Deform_GHZ_1: ; XREF: Deform_GHZ move.w d0,d4 move.w d0,($FFFFF618).w move.w ($FFFFF700).w,d0 cmpi.b #4,($FFFFF600).w bne.s Deform_GHZ_2 moveq #0,d0
Deform_GHZ_2: ; XREF: Deform_GHZ neg.w d0 swap d0 lea ($FFFFA800).w,a2 addi.l #$10000,(a2)+ addi.l #$C000,(a2)+ addi.l #$8000,(a2)+ move.w ($FFFFA800).w,d0 add.w ($FFFFF718).w,d0 neg.w d0 move.w #$1F,d1 sub.w d4,d1 bcs.s Deform_GHZ_4
Deform_GHZ_3: ; XREF: Deform_GHZ move.l d0,(a1)+ dbf d1,Deform_GHZ_3
Deform_GHZ_4: ; XREF: Deform_GHZ move.w ($FFFFA804).w,d0 add.w ($FFFFF718).w,d0 neg.w d0 move.w #$F,d1
Deform_GHZ_5: ; XREF: Deform_GHZ move.l d0,(a1)+ dbf d1,Deform_GHZ_5 move.w ($FFFFA808).w,d0 add.w ($FFFFF718).w,d0 neg.w d0 move.w #$F,d1
Deform_GHZ_6: ; XREF: Deform_GHZ move.l d0,(a1)+ dbf d1,Deform_GHZ_6 move.w #$2F,d1 ; '/' move.w ($FFFFF718).w,d0 neg.w d0
Deform_GHZ_7: ; XREF: Deform_GHZ move.l d0,(a1)+ dbf d1,Deform_GHZ_7 move.w #$27,d1 ; move.w ($FFFFF710).w,d0 neg.w d0
Deform_GHZ_8: ; XREF: Deform_GHZ move.l d0,(a1)+ dbf d1,Deform_GHZ_8 move.w ($FFFFF710).w,d0 move.w ($FFFFF700).w,d2 sub.w d0,d2 ext.l d2 asl.l #8,d2 divs.w #$68,d2 ; 'h' ext.l d2 asl.l #8,d2 moveq #0,d3 move.w d0,d3 move.w #$47,d1 ; 'G' add.w d4,d1
Deform_GHZ_9: ; XREF: Deform_GHZ move.w d3,d0 neg.w d0 move.l d0,(a1)+ swap d3 add.l d2,d3 swap d3 dbf d1,Deform_GHZ_9 rts
- End of function Deform_GHZ
- ||||||||||||||| S U B R O U T I N E |||||||||||||||||||||||||||||||||||||||
Deform_LZ:
move.w ($FFFFF73A).w,d4
ext.l d4
asl.l #7,d4
move.w ($FFFFF73C).w,d5
ext.l d5
asl.l #7,d5
bsr.w ScrollBlock1
move.w ($FFFFF70C).w,($FFFFF618).w
lea (LZ_Wave_Data).l,a3
lea (Obj0A_WobbleData).l,a2
move.b ($FFFFF7D8).w,d2
move.b d2,d3
addi.w #$80,($FFFFF7D8).w ; '€'
add.w ($FFFFF70C).w,d2
andi.w #$FF,d2
add.w ($FFFFF704).w,d3
andi.w #$FF,d3
lea ($FFFFCC00).w,a1
move.w #$DF,d1 ; 'ß'
move.w ($FFFFF700).w,d0
neg.w d0
move.w d0,d6
swap d0
move.w ($FFFFF708).w,d0
neg.w d0
move.w ($FFFFF646).w,d4
move.w ($FFFFF704).w,d5
Deform_LZ_1: ; XREF: Deform_LZ cmp.w d4,d5 bge.s Deform_LZ_2 move.l d0,(a1)+ addq.w #1,d5 addq.b #1,d2 addq.b #1,d3 dbf d1,Deform_LZ_1 rts
- ===========================================================================
Deform_LZ_2: ; XREF: Deform_LZ move.b (a3,d3.w),d4 ext.w d4 add.w d6,d4 move.w d4,(a1)+ move.b (a2,d2.w),d4 ext.w d4 add.w d0,d4 move.w d4,(a1)+ addq.b #1,d2 addq.b #1,d3 dbf d1,Deform_LZ_2 rts
- End of function Deform_LZ
- ===========================================================================
LZ_Wave_Data: dc.b 1, 1, 2, 2, 3, 3, 3, 3, 2, 2, 1, 1, 0, 0, 0, 0 dc.b 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 dc.b 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 dc.b 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 dc.b 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 dc.b 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 dc.b 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 dc.b 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 dc.b $FF,$FF,$FE,$FE,$FD,$FD,$FD,$FD,$FE,$FE,$FF,$FF, 0, 0, 0, 0 dc.b 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 dc.b 1, 1, 2, 2, 3, 3, 3, 3, 2, 2, 1, 1, 0, 0, 0, 0 dc.b 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 dc.b 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 dc.b 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 dc.b 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 dc.b 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
- ||||||||||||||| S U B R O U T I N E |||||||||||||||||||||||||||||||||||||||
Deform_MZ:
move.w ($FFFFF73A).w,d4
ext.l d4
asl.l #6,d4
move.l d4,d1
asl.l #1,d4
add.l d1,d4
moveq #2,d6
bsr.w ScrollBlock4
move.w ($FFFFF73A).w,d4
ext.l d4
asl.l #6,d4
moveq #6,d6
bsr.w ScrollBlock6
move.w ($FFFFF73A).w,d4
ext.l d4
asl.l #7,d4
moveq #4,d6
bsr.w ScrollBlock5
move.w #$200,d0
move.w ($FFFFF704).w,d1
subi.w #$1C8,d1
bcs.s Deform_MZ_1
move.w d1,d2
add.w d1,d1
add.w d2,d1
asr.w #2,d1
add.w d1,d0
Deform_MZ_1: ; XREF: Deform_MZ move.w d0,($FFFFF714).w move.w d0,($FFFFF71C).w bsr.w ScrollBlock3 move.w ($FFFFF70C).w,($FFFFF618).w move.b ($FFFFF756).w,d0 or.b ($FFFFF758).w,d0 or.b d0,($FFFFF75A).w clr.b ($FFFFF756).w clr.b ($FFFFF758).w lea ($FFFFA800).w,a1 move.w ($FFFFF700).w,d2 neg.w d2 move.w d2,d0 asr.w #2,d0 sub.w d2,d0 ext.l d0 asl.l #3,d0 divs.w #5,d0 ext.l d0 asl.l #4,d0 asl.l #8,d0 moveq #0,d3 move.w d2,d3 asr.w #1,d3 move.w #4,d1
Deform_MZ_2: ; XREF: Deform_MZ move.w d3,(a1)+ swap d3 add.l d0,d3 swap d3 dbf d1,Deform_MZ_2 move.w ($FFFFF718).w,d0 neg.w d0 move.w #1,d1
Deform_MZ_3: ; XREF: Deform_MZ move.w d0,(a1)+ dbf d1,Deform_MZ_3 move.w ($FFFFF710).w,d0 neg.w d0 move.w #8,d1
Deform_MZ_4: ; XREF: Deform_MZ move.w d0,(a1)+ dbf d1,Deform_MZ_4 move.w ($FFFFF708).w,d0 neg.w d0 move.w #$F,d1
Deform_MZ_5: ; XREF: Deform_MZ move.w d0,(a1)+ dbf d1,Deform_MZ_5 lea ($FFFFA800).w,a2 move.w ($FFFFF70C).w,d0 subi.w #$200,d0 move.w d0,d2 cmpi.w #$100,d0 bcs.s Deform_MZ_6 move.w #$100,d0
Deform_MZ_6: ; XREF: Deform_MZ andi.w #$1F0,d0 lsr.w #3,d0 lea (a2,d0.w),a2 bra.w Deform_All
- ===========================================================================
Deform_SLZ: move.w ($FFFFF73C).w,d5 ext.l d5 asl.l #7,d5 bsr.w ScrollBlock2 move.w ($FFFFF70C).w,($FFFFF618).w lea ($FFFFA800).w,a1 move.w ($FFFFF700).w,d2 neg.w d2 move.w d2,d0 asr.w #3,d0 sub.w d2,d0 ext.l d0 asl.l #4,d0 divs.w #$1C,d0 ext.l d0 asl.l #4,d0 asl.l #8,d0 moveq #0,d3 move.w d2,d3 move.w #$1B,d1
Deform_SLZ_1: ; XREF: Deform_MZ move.w d3,(a1)+ swap d3 add.l d0,d3 swap d3 dbf d1,Deform_SLZ_1 move.w d2,d0 asr.w #3,d0 move.w d0,d1 asr.w #1,d1 add.w d1,d0 move.w #4,d1
Deform_SLZ_2: ; XREF: Deform_MZ move.w d0,(a1)+ dbf d1,Deform_SLZ_2 move.w d2,d0 asr.w #2,d0 move.w #4,d1
Deform_SLZ_3: ; XREF: Deform_MZ move.w d0,(a1)+ dbf d1,Deform_SLZ_3 move.w d2,d0 asr.w #1,d0 move.w #$1D,d1
Deform_SLZ_4: ; XREF: Deform_MZ move.w d0,(a1)+ dbf d1,Deform_SLZ_4 lea ($FFFFA800).w,a2 move.w ($FFFFF70C).w,d0 move.w d0,d2 subi.w #$C0,d0 ; 'À' andi.w #$3F0,d0 lsr.w #3,d0 lea (a2,d0.w),a2
Deform_All: ; XREF: Deform_MZ, Deform_SYZ, ... lea ($FFFFCC00).w,a1 move.w #$E,d1 move.w ($FFFFF700).w,d0 neg.w d0 swap d0 andi.w #$F,d2 add.w d2,d2 move.w (a2)+,d0 jmp Deform_All_2(pc,d2.w)
- End of function Deform_MZ
- ===========================================================================
Deform_All_1: ; XREF: Deform_All move.w (a2)+,d0
Deform_All_2: move.l d0,(a1)+ move.l d0,(a1)+ move.l d0,(a1)+ move.l d0,(a1)+ move.l d0,(a1)+ move.l d0,(a1)+ move.l d0,(a1)+ move.l d0,(a1)+ move.l d0,(a1)+ move.l d0,(a1)+ move.l d0,(a1)+ move.l d0,(a1)+ move.l d0,(a1)+ move.l d0,(a1)+ move.l d0,(a1)+ move.l d0,(a1)+ dbf d1,Deform_All_1 rts
- ||||||||||||||| S U B R O U T I N E |||||||||||||||||||||||||||||||||||||||
Deform_SYZ:
move.w ($FFFFF73C).w,d5
ext.l d5
asl.l #4,d5
move.l d5,d1
asl.l #1,d5
add.l d1,d5
bsr.w ScrollBlock2
move.w ($FFFFF70C).w,($FFFFF618).w
lea ($FFFFA800).w,a1
move.w ($FFFFF700).w,d2
neg.w d2
move.w d2,d0
asr.w #3,d0
sub.w d2,d0
ext.l d0
asl.l #3,d0
divs.w #8,d0
ext.l d0
asl.l #4,d0
asl.l #8,d0
moveq #0,d3
move.w d2,d3
asr.w #1,d3
move.w #7,d1
Deform_SYZ_1: ; XREF: Deform_SYZ move.w d3,(a1)+ swap d3 add.l d0,d3 swap d3 dbf d1,Deform_SYZ_1 move.w d2,d0 asr.w #3,d0 move.w #4,d1
Deform_SYZ_2: ; XREF: Deform_SYZ move.w d0,(a1)+ dbf d1,Deform_SYZ_2 move.w d2,d0 asr.w #2,d0 move.w #5,d1
Deform_SYZ_3: ; XREF: Deform_SYZ move.w d0,(a1)+ dbf d1,Deform_SYZ_3 move.w d2,d0 move.w d2,d1 asr.w #1,d1 sub.w d1,d0 ext.l d0 asl.l #4,d0 divs.w #$E,d0 ext.l d0 asl.l #4,d0 asl.l #8,d0 moveq #0,d3 move.w d2,d3 asr.w #1,d3 move.w #$D,d1
Deform_SYZ_4: ; XREF: Deform_SYZ move.w d3,(a1)+ swap d3 add.l d0,d3 swap d3 dbf d1,Deform_SYZ_4 lea ($FFFFA800).w,a2 move.w ($FFFFF70C).w,d0 move.w d0,d2 andi.w #$1F0,d0 lsr.w #3,d0 lea (a2,d0.w),a2 bra.w Deform_All
- End of function Deform_SYZ
- ||||||||||||||| S U B R O U T I N E |||||||||||||||||||||||||||||||||||||||
Deform_SBZ:
tst.b ($FFFFFE11).w
bne.w Deform_SBZ_Act2
move.w ($FFFFF73A).w,d4
ext.l d4
asl.l #7,d4
moveq #2,d6
bsr.w ScrollBlock4
move.w ($FFFFF73A).w,d4
ext.l d4
asl.l #6,d4
moveq #6,d6
bsr.w ScrollBlock6
move.w ($FFFFF73A).w,d4
ext.l d4
asl.l #5,d4
move.l d4,d1
asl.l #1,d4
add.l d1,d4
moveq #4,d6
bsr.w ScrollBlock5
moveq #0,d4
move.w ($FFFFF73C).w,d5
ext.l d5
asl.l #5,d5
bsr.w ScrollBlock1_2
move.w ($FFFFF70C).w,d0
move.w d0,($FFFFF714).w
move.w d0,($FFFFF71C).w
move.w d0,($FFFFF618).w
move.b ($FFFFF756).w,d0
or.b ($FFFFF75A).w,d0
or.b d0,($FFFFF758).w
clr.b ($FFFFF756).w
clr.b ($FFFFF75A).w
lea ($FFFFA800).w,a1
move.w ($FFFFF700).w,d2
neg.w d2
asr.w #2,d2
move.w d2,d0
asr.w #1,d0
sub.w d2,d0
ext.l d0
asl.l #3,d0
divs.w #4,d0
ext.l d0
asl.l #4,d0
asl.l #8,d0
moveq #0,d3
move.w d2,d3
move.w #3,d1
Deform_SBZ_1: ; XREF: Deform_SBZ move.w d3,(a1)+ swap d3 add.l d0,d3 swap d3 dbf d1,Deform_SBZ_1 move.w ($FFFFF718).w,d0 neg.w d0 move.w #9,d1
Deform_SBZ_2: ; XREF: Deform_SBZ move.w d0,(a1)+ dbf d1,Deform_SBZ_2 move.w ($FFFFF710).w,d0 neg.w d0 move.w #6,d1
Deform_SBZ_3: ; XREF: Deform_SBZ move.w d0,(a1)+ dbf d1,Deform_SBZ_3 move.w ($FFFFF708).w,d0 neg.w d0 move.w #$A,d1
Deform_SBZ_4: ; XREF: Deform_SBZ move.w d0,(a1)+ dbf d1,Deform_SBZ_4 lea ($FFFFA800).w,a2 move.w ($FFFFF70C).w,d0 move.w d0,d2 andi.w #$1F0,d0 lsr.w #3,d0 lea (a2,d0.w),a2 bra.w Deform_All
- ===========================================================================
Deform_SBZ_Act2: ; XREF: Deform_SBZ move.w ($FFFFF73A).w,d4 ext.l d4 asl.l #6,d4 move.w ($FFFFF73C).w,d5 ext.l d5 asl.l #5,d5 bsr.w ScrollBlock1 move.w ($FFFFF70C).w,($FFFFF618).w lea ($FFFFCC00).w,a1 move.w #$DF,d1 ; 'ß' move.w ($FFFFF700).w,d0 neg.w d0 swap d0 move.w ($FFFFF708).w,d0 neg.w d0
Deform_SBZ_Act2_1: ; XREF: Deform_SBZ move.l d0,(a1)+ dbf d1,Deform_SBZ_Act2_1 rts
- End of function Deform_SBZ</asm>
Step 4
The new Bg drawing system required a different method of scrolling the BGs themselves. Go to ScrollBlock1 and replace everything from there until the end of ScrollBlock4 with the following: <asm>ScrollBlock1: ; XREF: Deform_LZ, Deform_SBZ move.l ($FFFFF708).w,d2 move.l d2,d0 add.l d4,d0 move.l d0,($FFFFF708).w move.l d0,d1 swap d1 andi.w #$10,d1 move.b ($FFFFF74C).w,d3 eor.b d3,d1 bne.s ScrollBlock1_2 eori.b #$10,($FFFFF74C).w sub.l d2,d0 bpl.s ScrollBlock1_1 bset #2,($FFFFF756).w bra.s ScrollBlock1_2
- ===========================================================================
ScrollBlock1_1: ; XREF: ScrollBlock1 bset #3,($FFFFF756).w
ScrollBlock1_2: ; XREF: ScrollBlock1, Deform_SBZ, ... move.l ($FFFFF70C).w,d3 move.l d3,d0 add.l d5,d0 move.l d0,($FFFFF70C).w move.l d0,d1 swap d1 andi.w #$10,d1 move.b ($FFFFF74D).w,d2 eor.b d2,d1 bne.s ScrollBlock1_End eori.b #$10,($FFFFF74D).w sub.l d3,d0 bpl.s ScrollBlock1_3 bset #0,($FFFFF756).w rts
- ===========================================================================
ScrollBlock1_3: ; XREF: ScrollBlock1 bset #1,($FFFFF756).w
ScrollBlock1_End: ; XREF: ScrollBlock1 rts
- End of function ScrollBlock1
- ||||||||||||||| S U B R O U T I N E |||||||||||||||||||||||||||||||||||||||
ScrollBlock2: ; XREF: Deform_MZ, Deform_SYZ
move.l ($FFFFF70C).w,d3
move.l d3,d0
add.l d5,d0
move.l d0,($FFFFF70C).w
move.l d0,d1
swap d1
andi.w #$10,d1
move.b ($FFFFF74D).w,d2
eor.b d2,d1
bne.s ScrollBlock2_End
eori.b #$10,($FFFFF74D).w
sub.l d3,d0
bpl.s ScrollBlock2_1
bset #4,($FFFFF756).w
rts
- ===========================================================================
ScrollBlock2_1: ; XREF: ScrollBlock2 bset #5,($FFFFF756).w
ScrollBlock2_End: ; XREF: ScrollBlock2 rts
- End of function ScrollBlock2
- ||||||||||||||| S U B R O U T I N E |||||||||||||||||||||||||||||||||||||||
ScrollBlock3: ; XREF: Deform_MZ
move.w ($FFFFF70C).w,d3
move.w d0,($FFFFF70C).w
move.w d0,d1
andi.w #$10,d1
move.b ($FFFFF74D).w,d2
eor.b d2,d1
bne.s ScrollBlock3_End
eori.b #$10,($FFFFF74D).w
sub.w d3,d0
bpl.s ScrollBlock3_1
bset #0,($FFFFF756).w
rts
- ===========================================================================
ScrollBlock3_1: ; XREF: ScrollBlock3 bset #1,($FFFFF756).w
ScrollBlock3_End: ; XREF: ScrollBlock3 rts
- End of function ScrollBlock3
- ||||||||||||||| S U B R O U T I N E |||||||||||||||||||||||||||||||||||||||
ScrollBlock4: ; XREF: Deform_MZ, Deform_SBZ
move.l ($FFFFF708).w,d2
move.l d2,d0
add.l d4,d0
move.l d0,($FFFFF708).w
move.l d0,d1
swap d1
andi.w #$10,d1
move.b ($FFFFF74C).w,d3
eor.b d3,d1
bne.s ScrollBlock4_End
eori.b #$10,($FFFFF74C).w
sub.l d2,d0
bpl.s ScrollBlock4_1
bset d6,($FFFFF756).w
bra.s ScrollBlock4_End
- ===========================================================================
ScrollBlock4_1: ; XREF: ScrollBlock4 addq.b #1,d6 bset d6,($FFFFF756).w
ScrollBlock4_End: ; XREF: ScrollBlock4 rts
- End of function ScrollBlock4
- ||||||||||||||| S U B R O U T I N E |||||||||||||||||||||||||||||||||||||||
ScrollBlock5: ; XREF: Deform_GHZ, Deform_MZ, ...
move.l ($FFFFF710).w,d2
move.l d2,d0
add.l d4,d0
move.l d0,($FFFFF710).w
move.l d0,d1
swap d1
andi.w #$10,d1
move.b ($FFFFF74E).w,d3
eor.b d3,d1
bne.s ScrollBlock5_End
eori.b #$10,($FFFFF74E).w
sub.l d2,d0
bpl.s ScrollBlock5_1
bset d6,($FFFFF758).w
bra.s ScrollBlock5_End
- ===========================================================================
ScrollBlock5_1: ; XREF: ScrollBlock5 addq.b #1,d6 bset d6,($FFFFF758).w
ScrollBlock5_End: ; XREF: ScrollBlock5 rts
- End of function ScrollBlock5
- ||||||||||||||| S U B R O U T I N E |||||||||||||||||||||||||||||||||||||||
ScrollBlock6: ; XREF: Deform_GHZ, Deform_MZ, ...
move.l ($FFFFF718).w,d2
move.l d2,d0
add.l d4,d0
move.l d0,($FFFFF718).w
move.l d0,d1
swap d1
andi.w #$10,d1
move.b ($FFFFF750).w,d3
eor.b d3,d1
bne.s ScrollBlock6_End
eori.b #$10,($FFFFF750).w
sub.l d2,d0
bpl.s ScrollBlock6_1
bset d6,($FFFFF75A).w
bra.s ScrollBlock6_End
- ===========================================================================
ScrollBlock6_1: ; XREF: ScrollBlock6 addq.b #1,d6 bset d6,($FFFFF75A).w
ScrollBlock6_End: ; XREF: ScrollBlock6 rts
- End of function ScrollBlock6</asm>
Don't worry that there are six BGScroll functions now, that's taken cared of.
Step 5
Finally, the biggest part: the BG drawing code. Go to sub_6886 and replace everything from there until the end of LoadTilesFromStart2 (that's a VERY long way, up until MainLoadBlockLoad) with the following: <asm>sub_6886: lea ($C00004).l,a5 lea ($C00000).l,a6 lea ($FFFFF756).w,a2 lea ($FFFFF708).w,a3 lea ($FFFFA440).w,a4 move.w #$6000,d2 bsr.w sub_6D0A lea ($FFFFF758).w,a2 lea ($FFFFF710).w,a3 bra.w sub_6DA6
- End of function sub_6886
- ---------------------------------------------------------------------------
- Subroutine to display correct tiles as you move
- ---------------------------------------------------------------------------
- ||||||||||||||| S U B R O U T I N E |||||||||||||||||||||||||||||||||||||||
LoadTilesAsYouMove: ; XREF: Demo_Time
lea ($C00004).l,a5
lea ($C00000).l,a6
lea ($FFFFFF32).w,a2
lea ($FFFFFF18).w,a3
lea ($FFFFA440).w,a4
move.w #$6000,d2
bsr.w sub_6D0A
lea ($FFFFFF34).w,a2
lea ($FFFFFF20).w,a3
bsr.w sub_6DA6
lea ($FFFFFF36).w,a2
lea ($FFFFFF28).w,a3
bsr.w sub_6EA4
lea ($FFFFFF30).w,a2
lea ($FFFFFF10).w,a3
lea ($FFFFA400).w,a4
move.w #$4000,d2
tst.b ($FFFFF745).w
beq.s Draw_FG
move.b #0,($FFFFF745).w ;Reset the redraw flag
moveq #-$10,d4 ;Go to top line oflevel data relative camera position
moveq #$F,d6 ;
Draw_All: movem.l d4-d6,-(sp) ; This whole routine basically redraws the whole moveq #-$10,d5 ; area instead of merely a line of tiles move.w d4,d1 bsr.w Calc_VRAM_Pos move.w d1,d4 moveq #-$10,d5 bsr.w DrawTiles_LR movem.l (sp)+,d4-d6 addi.w #$10,d4 dbf d6,Draw_All rts
Draw_FG: tst.b (a2) beq.s locret_6D08 bclr #0,(a2) beq.s loc_6CBE moveq #-$10,d4 moveq #-$10,d5 bsr.w Calc_VRAM_Pos moveq #-$10,d4 moveq #-$10,d5 bsr.w DrawTiles_LR
loc_6CBE: bclr #1,(a2) beq.s loc_6CD8 move.w #$E0,d4 ; 'à' moveq #-$10,d5 bsr.w Calc_VRAM_Pos move.w #$E0,d4 ; 'à' moveq #-$10,d5 bsr.w DrawTiles_LR
loc_6CD8: bclr #2,(a2) beq.s loc_6CEE moveq #-$10,d4 moveq #-$10,d5 bsr.w Calc_VRAM_Pos moveq #-$10,d4 moveq #-$10,d5 bsr.w DrawTiles_TB
loc_6CEE: bclr #3,(a2) beq.s locret_6D08 moveq #-$10,d4 move.w #$140,d5 bsr.w Calc_VRAM_Pos moveq #-$10,d4 move.w #$140,d5 bsr.w DrawTiles_TB
locret_6D08: rts
- End of function LoadTilesAsYouMove
- ||||||||||||||| S U B R O U T I N E |||||||||||||||||||||||||||||||||||||||
sub_6D0A:
tst.b (a2)
beq.w locret_6DA4
bclr #0,(a2)
beq.s loc_6D26
moveq #-$10,d4
moveq #-$10,d5
bsr.w Calc_VRAM_Pos
moveq #-$10,d4
moveq #-$10,d5
bsr.w DrawTiles_LR
loc_6D26: bclr #1,(a2) beq.s loc_6D40 move.w #$E0,d4 ; 'à' moveq #-$10,d5 bsr.w Calc_VRAM_Pos move.w #$E0,d4 ; 'à' moveq #-$10,d5 bsr.w DrawTiles_LR
loc_6D40: bclr #2,(a2) beq.s loc_6D56 moveq #-$10,d4 moveq #-$10,d5 bsr.w Calc_VRAM_Pos moveq #-$10,d4 moveq #-$10,d5 bsr.w DrawTiles_TB
loc_6D56: bclr #3,(a2) beq.s loc_6D70 moveq #-$10,d4 move.w #$140,d5 bsr.w Calc_VRAM_Pos moveq #-$10,d4 move.w #$140,d5 bsr.w DrawTiles_TB
loc_6D70: bclr #4,(a2) beq.s loc_6D88 moveq #-$10,d4 moveq #0,d5 bsr.w loc_7176 moveq #-$10,d4 moveq #0,d5 moveq #$1F,d6 bsr.w DrawTiles_LR3
loc_6D88: bclr #5,(a2) beq.s locret_6DA4 move.w #$E0,d4 ; 'à' moveq #0,d5 bsr.w loc_7176 move.w #$E0,d4 ; 'à' moveq #0,d5 moveq #$1F,d6 bsr.w DrawTiles_LR3
locret_6DA4: rts
- End of function sub_6D0A
- ||||||||||||||| S U B R O U T I N E |||||||||||||||||||||||||||||||||||||||
sub_6DA6:
tst.b (a2)
beq.w locret_6DF2
cmpi.b #5,($FFFFFE10).w
beq.w loc_6E16
bclr #0,(a2)
beq.s loc_6DD2
move.w #$70,d4 ; 'p'
moveq #-$10,d5
bsr.w Calc_VRAM_Pos
move.w #$70,d4 ; 'p'
moveq #-$10,d5
moveq #2,d6
bsr.w DrawTiles_TB2
loc_6DD2: bclr #1,(a2) beq.s locret_6DF2 move.w #$70,d4 ; 'p' move.w #$140,d5 bsr.w Calc_VRAM_Pos move.w #$70,d4 ; 'p' move.w #$140,d5 moveq #2,d6 bsr.w DrawTiles_TB2
locret_6DF2: rts
- ===========================================================================
unk_6DF4: dc.b 0 ; unk_6DF5: dc.b 0 ; dc.b 0 ; dc.b 0 ; dc.b 0 ; dc.b 6 ; dc.b 6 ; dc.b 6 ; dc.b 6 ; dc.b 6 ; dc.b 6 ; dc.b 6 ; dc.b 6 ; dc.b 6 ; dc.b 6 ; dc.b 4 ; dc.b 4 ; dc.b 4 ; dc.b 4 ; dc.b 4 ; dc.b 4 ; dc.b 4 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 0 ;
- ===========================================================================
loc_6E16: moveq #-$10,d4 bclr #0,(a2) bne.s loc_6E28 bclr #1,(a2) beq.s loc_6E72 move.w #$E0,d4 ; 'à'
loc_6E28: lea (unk_6DF5).l,a0 move.w ($FFFFF70C).w,d0 add.w d4,d0 andi.w #$1F0,d0 lsr.w #4,d0 move.b (a0,d0.w),d0 lea (unk_6FE4).l,a3 movea.w (a3,d0.w),a3 beq.s loc_6E5E moveq #-$10,d5 movem.l d4-d5,-(sp) bsr.w Calc_VRAM_Pos movem.l (sp)+,d4-d5 bsr.w DrawTiles_LR bra.s loc_6E72
- ===========================================================================
loc_6E5E: moveq #0,d5 movem.l d4-d5,-(sp) bsr.w loc_7176 movem.l (sp)+,d4-d5 moveq #$1F,d6 bsr.w DrawTiles_LR3
loc_6E72: tst.b (a2) bne.s loc_6E78 rts
- ===========================================================================
loc_6E78: moveq #-$10,d4 moveq #-$10,d5 move.b (a2),d0 andi.b #-$58,d0 beq.s loc_6E8C lsr.b #1,d0 move.b d0,(a2) move.w #$140,d5
loc_6E8C: lea (unk_6DF4).l,a0 move.w ($FFFFF70C).w,d0 andi.w #$1F0,d0 lsr.w #4,d0 lea (a0,d0.w),a0 bra.w loc_6FEC
- End of function sub_6DA6
- ||||||||||||||| S U B R O U T I N E |||||||||||||||||||||||||||||||||||||||
sub_6EA4:
tst.b (a2)
beq.w locret_6EF0
cmpi.b #2,($FFFFFE10).w
beq.w loc_6F54
bclr #0,(a2)
beq.s loc_6ED0_2
move.w #$40,d4 ; '@'
moveq #-$10,d5
bsr.w Calc_VRAM_Pos
move.w #$40,d4 ; '@'
moveq #-$10,d5
moveq #2,d6
bsr.w DrawTiles_TB2
loc_6ED0_2: bclr #1,(a2) beq.s locret_6EF0 move.w #$40,d4 ; '@' move.w #$140,d5 bsr.w Calc_VRAM_Pos move.w #$40,d4 ; '@' move.w #$140,d5 moveq #2,d6 bsr.w DrawTiles_TB2
locret_6EF0: rts
- ===========================================================================
unk_6EF2: dc.b 0 ; unk_6EF3: dc.b 0 ; dc.b 0 ; dc.b 0 ; dc.b 0 ; dc.b 0 ; dc.b 6 ; dc.b 6 ; dc.b 4 ; dc.b 4 ; dc.b 4 ; dc.b 4 ; dc.b 4 ; dc.b 4 ; dc.b 4 ; dc.b 4 ; dc.b 4 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 2 ; dc.b 0 ;
- ===========================================================================
loc_6F54: moveq #-$10,d4 bclr #0,(a2) bne.s loc_6F66 bclr #1,(a2) beq.s loc_6FAE move.w #$E0,d4 ; 'à'
loc_6F66: lea (unk_6EF3).l,a0 move.w ($FFFFF70C).w,d0 subi.w #$200,d0 add.w d4,d0 andi.w #$7F0,d0 lsr.w #4,d0 move.b (a0,d0.w),d0 movea.w unk_6FE4(pc,d0.w),a3 beq.s loc_6F9A moveq #-$10,d5 movem.l d4-d5,-(sp) bsr.w Calc_VRAM_Pos movem.l (sp)+,d4-d5 bsr.w DrawTiles_LR bra.s loc_6FAE
- ===========================================================================
loc_6F9A: moveq #0,d5 movem.l d4-d5,-(sp) bsr.w loc_7176 movem.l (sp)+,d4-d5 moveq #$1F,d6 bsr.w DrawTiles_LR3
loc_6FAE: tst.b (a2) bne.s loc_6FB4 rts
- ===========================================================================
loc_6FB4: moveq #-$10,d4 moveq #-$10,d5 move.b (a2),d0 andi.b #-$58,d0 beq.s loc_6FC8 lsr.b #1,d0 move.b d0,(a2) move.w #$140,d5
loc_6FC8: lea (unk_6EF2).l,a0 move.w ($FFFFF70C).w,d0 subi.w #$200,d0 andi.w #$7F0,d0 lsr.w #4,d0 lea (a0,d0.w),a0 bra.w loc_6FEC
- ===========================================================================
unk_6FE4: dc.b $FF ; dc.b $18 ; dc.b $FF ; dc.b $18 ; dc.b $FF ; dc.b $20 ; dc.b $FF ; dc.b $28 ; (
- ===========================================================================
loc_6FEC: moveq #$F,d6 move.l #$800000,d7
loc_6FF4: moveq #0,d0 move.b (a0)+,d0 btst d0,(a2) beq.s loc_701C movea.w unk_6FE4(pc,d0.w),a3 movem.l d4-d5/a0,-(sp) movem.l d4-d5,-(sp) bsr.w sub_712A movem.l (sp)+,d4-d5 bsr.w Calc_VRAM_Pos bsr.w sub_70AC movem.l (sp)+,d4-d5/a0
loc_701C: addi.w #$10,d4 dbf d6,loc_6FF4 clr.b (a2) rts
- End of function sub_6EA4
- ||||||||||||||| S U B R O U T I N E |||||||||||||||||||||||||||||||||||||||
DrawTiles_LR:
moveq #$15,d6
- End of function DrawTiles_LR
- ||||||||||||||| S U B R O U T I N E |||||||||||||||||||||||||||||||||||||||
DrawTiles_LR2:
move.l #$800000,d7
move.l d0,d1
loc_7032: movem.l d4-d5,-(sp) bsr.w sub_712A move.l d1,d0 bsr.w sub_70AC addq.b #4,d1 andi.b #$7F,d1 ; '?' movem.l (sp)+,d4-d5 addi.w #$10,d5 dbf d6,loc_7032 rts
- End of function DrawTiles_LR2
- ||||||||||||||| S U B R O U T I N E |||||||||||||||||||||||||||||||||||||||
DrawTiles_LR3:
move.l #$800000,d7
move.l d0,d1
loc_705C: movem.l d4-d5,-(sp) bsr.w loc_712C move.l d1,d0 bsr.w sub_70AC addq.b #4,d1 andi.b #$7F,d1 ; '?' movem.l (sp)+,d4-d5 addi.w #$10,d5 dbf d6,loc_705C rts
- End of function DrawTiles_LR3
- ||||||||||||||| S U B R O U T I N E |||||||||||||||||||||||||||||||||||||||
DrawTiles_TB:
moveq #$F,d6
- End of function DrawTiles_TB
- ||||||||||||||| S U B R O U T I N E |||||||||||||||||||||||||||||||||||||||
DrawTiles_TB2:
move.l #$800000,d7
move.l d0,d1
loc_7088: movem.l d4-d5,-(sp) bsr.w sub_712A move.l d1,d0 bsr.w sub_70AC addi.w #$100,d1 andi.w #$FFF,d1 movem.l (sp)+,d4-d5 addi.w #$10,d4 dbf d6,loc_7088 rts
- End of function DrawTiles_TB2
- ||||||||||||||| S U B R O U T I N E |||||||||||||||||||||||||||||||||||||||
sub_70AC:
or.w d2,d0
swap d0
btst #4,(a0)
bne.s loc_70E8
btst #3,(a0)
bne.s loc_70C8
move.l d0,(a5)
move.l (a1)+,(a6)
add.l d7,d0
move.l d0,(a5)
move.l (a1)+,(a6)
rts
- ===========================================================================
loc_70C8: move.l d0,(a5) move.l (a1)+,d4 eori.l #$8000800,d4 swap d4 move.l d4,(a6) add.l d7,d0 move.l d0,(a5) move.l (a1)+,d4 eori.l #$8000800,d4 swap d4 move.l d4,(a6) rts
- ===========================================================================
loc_70E8: btst #3,(a0) bne.s loc_710A move.l d0,(a5) move.l (a1)+,d5 move.l (a1)+,d4 eori.l #$10001000,d4 move.l d4,(a6) add.l d7,d0 move.l d0,(a5) eori.l #$10001000,d5 move.l d5,(a6) rts
- ===========================================================================
loc_710A: move.l d0,(a5) move.l (a1)+,d5 move.l (a1)+,d4 eori.l #$18001800,d4 swap d4 move.l d4,(a6) add.l d7,d0 move.l d0,(a5) eori.l #$18001800,d5 swap d5 move.l d5,(a6) rts
- End of function sub_70AC
- ||||||||||||||| S U B R O U T I N E |||||||||||||||||||||||||||||||||||||||
sub_712A:
add.w (a3),d5
loc_712C: add.w 4(a3),d4 lea ($FFFFB000).w,a1 move.w d4,d3 lsr.w #1,d3 andi.w #$380,d3 lsr.w #3,d5 move.w d5,d0 lsr.w #5,d0 andi.w #$7F,d0 ; '?' add.w d3,d0 moveq #-1,d3 move.b (a4,d0.w),d3 beq.s locret_7172 subq.b #1,d3 andi.w #$7F,d3 ; '?' ror.w #7,d3 add.w d4,d4 andi.w #$1E0,d4 andi.w #$1E,d5 add.w d4,d3 add.w d5,d3 movea.l d3,a0 move.w (a0),d3 andi.w #$3FF,d3 lsl.w #3,d3 adda.w d3,a1
locret_7172: rts
- End of function sub_712A
- ||||||||||||||| S U B R O U T I N E |||||||||||||||||||||||||||||||||||||||
Calc_VRAM_Pos:
add.w (a3),d5
loc_7176: add.w 4(a3),d4 andi.w #$F0,d4 ; 'ð' andi.w #$1F0,d5 lsl.w #4,d4 lsr.w #2,d5 add.w d5,d4 moveq #3,d0 swap d0 move.w d4,d0 rts
- End of function Calc_VRAM_Pos
- ===========================================================================
add.w 4(a3),d4 add.w (a3),d5 andi.w #$F0,d4 ; 'ð' andi.w #$1F0,d5 lsl.w #4,d4 lsr.w #2,d5 add.w d5,d4 moveq #2,d0 swap d0 move.w d4,d0 rts
- ||||||||||||||| S U B R O U T I N E |||||||||||||||||||||||||||||||||||||||
LoadTilesFromStart:
lea ($C00004).l,a5
lea ($C00000).l,a6
lea ($FFFFF700).w,a3
lea ($FFFFA400).w,a4
move.w #$4000,d2
bsr.s LoadTilesFromStart2
lea ($FFFFF708).w,a3
lea ($FFFFA440).w,a4
move.w #$6000,d2
tst.b ($FFFFFE10).w
beq.w loc_7220
cmpi.b #2,($FFFFFE10).w
beq.w loc_725A
cmpi.w #$500,($FFFFFE10).w
beq.w loc_7288
cmpi.b #6,($FFFFFE10).w
beq.w loc_7220
- End of function LoadTilesFromStart
- ||||||||||||||| S U B R O U T I N E |||||||||||||||||||||||||||||||||||||||
LoadTilesFromStart2:
moveq #-$10,d4
moveq #$F,d6
loc_71FC: movem.l d4-d6,-(sp) moveq #0,d5 move.w d4,d1 bsr.w Calc_VRAM_Pos move.w d1,d4 moveq #0,d5 moveq #$1F,d6 bsr.w DrawTiles_LR2 movem.l (sp)+,d4-d6 addi.w #$10,d4 dbf d6,loc_71FC rts
- End of function LoadTilesFromStart2
- ===========================================================================
loc_7220: moveq #0,d4 moveq #$F,d6
loc_7224: movem.l d4-d6,-(sp) lea (unk_724A).l,a0 move.w ($FFFFF70C).w,d0 add.w d4,d0 andi.w #$F0,d0 ; 'ð' bsr.w sub_72BA movem.l (sp)+,d4-d6 addi.w #$10,d4 dbf d6,loc_7224 rts
- ===========================================================================
unk_724A: dc.b 0 ; dc.b 0 ; dc.b 0 ; dc.b 0 ; dc.b 6 ; dc.b 6 ; dc.b 6 ; dc.b 4 ; dc.b 4 ; dc.b 4 ; dc.b 0 ; dc.b 0 ; dc.b 0 ; dc.b 0 ; dc.b 0 ; dc.b 0 ;
- ===========================================================================
loc_725A: moveq #-$10,d4 moveq #$F,d6
loc_725E: movem.l d4-d6,-(sp) lea (unk_6EF3).l,a0 move.w ($FFFFF70C).w,d0 subi.w #$200,d0 add.w d4,d0 andi.w #$7F0,d0 bsr.w sub_72BA movem.l (sp)+,d4-d6 addi.w #$10,d4 dbf d6,loc_725E rts
- ===========================================================================
loc_7288: moveq #-$10,d4 moveq #$F,d6
loc_728C: movem.l d4-d6,-(sp) lea (unk_6DF5).l,a0 move.w ($FFFFF70C).w,d0 add.w d4,d0 andi.w #$1F0,d0 bsr.w sub_72BA movem.l (sp)+,d4-d6 addi.w #$10,d4 dbf d6,loc_728C rts
- ===========================================================================
unk_72B2: dc.b $F7 ; ÷ dc.b 8 ; dc.b $F7 ; ÷ dc.b 8 ; dc.b $F7 ; ÷ dc.b $10 ; dc.b $F7 ; ÷ dc.b $18 ;
- ||||||||||||||| S U B R O U T I N E |||||||||||||||||||||||||||||||||||||||
sub_72BA:
lsr.w #4,d0
move.b (a0,d0.w),d0
movea.w unk_72B2(pc,d0.w),a3
beq.s loc_72DA
moveq #-$10,d5
movem.l d4-d5,-(sp)
bsr.w Calc_VRAM_Pos
movem.l (sp)+,d4-d5
bsr.w DrawTiles_LR
bra.s locret_72EE
- ===========================================================================
loc_72DA: moveq #0,d5 movem.l d4-d5,-(sp) bsr.w loc_7176 movem.l (sp)+,d4-d5 moveq #$1F,d6 bsr.w DrawTiles_LR3
locret_72EE: rts
- End of function sub_72BA</asm>
Step 6
Assuming you haven't changed the backgrounds of your levels, compile it and give it a go!
Credits
- Hivebrain - for attempting this first
- Tweaker - for his assistance when I had some issues to resolve.
Extra step
If you get errors upon compiling, you'll need to follow this extra step.
Fixing the errors
Alright, so after you've followed the main guide, you'll need to go here in your disasm: <asm>Obj89: ; XREF: Obj_Index moveq #0,d0 move.b $24(a0),d0 move.w Obj89_Index(pc,d0.w),d1 jmp Obj89_Index(pc,d1.w)
- ===========================================================================
Obj89_Index: dc.w Obj89_Main-Obj89_Index dc.w Obj89_Move-Obj89_Index dc.w Obj89_GotoCredits-Obj89_Index
- ===========================================================================
Obj89_Main: ; XREF: Obj89_Index addq.b #2,$24(a0) move.w #-$20,8(a0) ; object starts outside the level boundary move.w #$D8,$A(a0) move.l #Map_obj89,4(a0) move.w #$5C5,2(a0) move.b #0,1(a0) move.b #0,$18(a0)
Obj89_Move: ; XREF: Obj89_Index cmpi.w #$C0,8(a0) ; has object reached $C0? beq.s Obj89_Delay ; if yes, branch addi.w #$10,8(a0) ; move object to the right bra.w DisplaySprite
- ===========================================================================
Obj89_Delay: ; XREF: Obj89_Move addq.b #2,$24(a0) move.w #120,$30(a0) ; set duration for delay (2 seconds)
Obj89_GotoCredits: ; XREF: Obj89_Index subq.w #1,$30(a0) ; subtract 1 from duration bpl.s Obj89_Display move.b #$1C,($FFFFF600).w ; exit to credits
Obj89_Display: bra.w DisplaySprite</asm> You should see this line occurring twice: <asm> bra.w DisplaySprite</asm> This is the problem. The code you just installed for the better background effects is bigger than the original code, and those lines that I mentioned have a specific branch range. Since some code has shifted, it is now out of range, causing the error. So let's change this code to something a bit more, shall I say, pliable. So, replace those two lines with this: <asm> jmp DisplaySprite</asm> That simple "jmp" command should do the trick.
And that's it! The errors should be gone! (If you still get errors, leave a message on this guide's talk page explaining how it all happens and I'll try to create a fix for it.) Have fun, and enjoy the Rev01 background effects!
(Oh, and you can still use this fix without following the actual guide, as it still works, and should make your life easier in case something else happens like the error I just explained above.)