Homing Attack in Sonic 1 - Step 7 - Sound and Uncontrolled Jump

How to: Add a Sound

below these lines:

Code:

HA_calcdistance2:      ; continuation of distance calculator
      muls.w  d1,d1   ; horizontal distance squared
      muls.w  d2,d2   ; vertical distance squared
      add.l  d2,d1   ; add vertical distance to horizontal distance
      cmp.l  #16384,d1      ; is distance of Sonic, greater than or equal 128 pixels of the object? (128^2=16384 // $80^2=$4000)
      bge.s  HA_nextobject   ; if yes, don't execute the homing attack

add this:

Code:

      move.w   #$BC,d0            ; set homing attack sound
      jsr   (PlaySound).l         ; play homing attack sound

BC is the sound will be played.


Jump Uncontrolled

When rolling, if you make a jump, your jump will be "uncontrolled". This condition is bad after the Homing Attack, because you can't move the Sonic after the bounce.

To correct this, go below these lines:

Code:

      move.w   #$BC,d0            ; set homing attack sound
      jsr   (PlaySound).l         ; play homing attack sound


and add this:

Code:

      bclr   #4,$22(a0)         ; clear "uncontrolled jump" flag

Can i use this code (all steps) in sonic 2 as well?

Yes.

.

v

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