Some changes and fixes for Sonic 2

Has the bug in VS mode concerning the power up music changes staying on if the utilising player loses a life got a fix?

 

I could've sworn I made a fix for this at some point, but I can't find it anymore. Anyway, here's the fix:

Code (Text):

1. ; loc_3F926: KillSonic:
2. KillCharacter:
3.     tst.w    (Debug_placement_mode).w
4.     bne.s    .return
5.  
6. ;-------- bugfix --------
7. ; reset stats and music upon death
8.     move.w    #1,invincibility_time(a0)    ; make invincibility run out
9.     move.w    #1,speedshoes_time(a0)        ; make speed shoes run out
10.     cmpa.w    #MainCharacter,a0
11.     bne.s    .p2
12.  
13.     tst.b    (Super_Sonic_flag).w
14.     beq.s    .notSuper
15.  
16.     move.b    #0,(Super_Sonic_flag).w        ; remove super status
17.     move.b    #2,(Super_Sonic_palette).w
18.     move.w    #$28,(Palette_frame).w
19.  
20. .notSuper:
21.     jsr    (Obj01_ChkInvin).l    ; remove player 1's power ups
22.     bra.s    .kill
23.  
24. .p2:
25.     jsr    (Obj02_ChkInvinc).l    ; remove player 2's power ups
26. ;---- end bugfix --------
27.  
28.  
29. .kill:
30.     clr.b    status_secondary(a0)
31.     move.b    #6,routine(a0)
32.     jsrto    (Sonic_ResetOnFloor_Part2).l, JmpTo_Sonic_ResetOnFloor_Part2
33.     bset    #1,status(a0)
34.     move.w    #-$700,y_vel(a0)
35.     move.w    #0,x_vel(a0)
36.     move.w    #0,inertia(a0)
37.     move.b    #AniIDSonAni_Death,anim(a0)
38.     bset    #high_priority_bit,art_tile(a0)
39.     move.w    #SndID_Hurt,d0
40.     cmpi.b    #ObjID_Spikes,id(a2)
41.     bne.s    .playSound
42.     move.w    #SndID_HurtBySpikes,d0
43.  
44. .playSound:
45.     jsr    (PlaySound).l
46.  
47. .return:
48.     moveq    #-1,d0
49.     rts

The changes are between the two bugfix comments. The only other thing I changes was replace the nameless temporary symbols with named local symbols. As a bonus, I threw in a Super Sonic detransformation.

 

You probably did, but this is a hard to track gold mine of fixes now. :P

 

If anything, it's hidden away on an old hard drive somewhere. I have at least one old disassembly somewhere with a bunch of bugfixes that I never published.

 

Here is one more design choice change that can be made.
Extending the limit to how many frames Sonic, Tails or Knuckles can have!

Now, this is a bit limited due to how the animation subroutine for player characters works, but it does allow for more frames than what the game normally allows.
In this example, I will be using Sonic. However, this can be applied to Tails or Knuckles as well.

For Sonic, locate the label

Code (Text):

1. SAnim_Do2

now, look for a line that reads

Code (Text):

1. cmpi.b    #$F0,d0

Change this to

Code (Text):

1. cmpi.b    #$FD,d0

This will allow for 12 more frames of animation!

Edit: Actually, change it to $FD, as this is supposed to be the number AFTER the max amount of frames. Therefore, setting to $FD allows for $FC amount of frames to be usable.