[Scummvm-tracker] [ScummVM] #9894: QFG4: Thieves guild secret passage isn't immediately walkable

[ScummVM]

#9894: QFG4: Thieves guild secret passage isn't immediately walkable
--------------------------------+----------------------------------------
  Reporter:  tsoliman           |      Owner:  (none)
      Type:  defect             |     Status:  new
  Priority:  normal             |  Component:  Engine: SCI
Resolution:                     |   Keywords:  SCI32 original pathfinding
      Game:  Quest for Glory 4  |
--------------------------------+----------------------------------------

Comment (by Vhati):

 Looks like sBarrelMove has derelict code.

 At some point during development, it was possible to move the barrel back
 and forth, re-hiding the puzzle mechanism. Now it only reveals once and
 stays put.
 \\
 \\
 script 340 - barrel::doVerb(4)
 {{{
 (cond
         # Passage revealed flag.
         ((proc0_4 254)
                 # "You don't need to do anything else with the
                 #   barrel. Don't bungle the job!"
                 (global91 say: 6 4 27)
         )
         # Desk opened flag.
         ((proc0_4 241)
                 # x=116 if the barrel has already been moved to reveal the
 puzzle.

                 (if (== x 116)
                         (g2_myCurrentRoom setScript: sBarrelMove 0 1)
                 else
                         (g2_myCurrentRoom setScript: sBarrelMove 0 0)
                 )

                 # Those lines schedule sBarrelMove with "register" set to
 1 or 0.
         )
         (else
                 # "There does seem to be something under this barrel,
                 #   but you've got no clue of what to do with it."
                 (g91_gloryMessager say: 6 4 104)
         )
 )
 }}}
 Because a cond block short-circuits, if sBarrelMove is scheduled, flag 254
 can't have been set. So when sBarrelMove tests the flag, it will always be
 false.
 \\
 \\
 \\
 script 340 - sBarrelMove::changeState()
 {{{
 (0
         0
         (global1 handsOff:)
         (if
                 # x=116 and register=1 are synonymous.
                 # Flag 254 is never true here.
                 (and (== (barrel x?) 116) (not (proc0_4 254)))
                 (self changeState: 6)
         else
                 # States 1-5 will only run with x != 116, aka register=0.
                 (= cycles 1)
         )
 )
 # ...
 (2
         2
         (if register
                 # "You slide the barrel back into place covering
                 #   the lock mechanism."
                 (global91 say: 6 4 18 0 self)
         else
                 # "You depress the barrel tap, but nothing comes out.
                 #   Instead, the barrel slides across the wall to reveal
                 #   some sort of mechanism."
                 (global91 say: 6 4 19 0 self)
         )
 )
 (3
         3
         (barrel setLoop:)
         (if register
                 (barrel setMotion: MoveTo 132 148 self)
         else
                 (barrel setMotion: MoveTo 116 148 self)
         )
 )
 # ...
 (5
         5
         (g0_hero
                 normalize:
                 cycleSpeed: local4
                 posn: (if register 149 else 159) 131
         )
         (if register (= state 11))
         (= cycles 1)
 )
 }}}
 Any code in states 1-5 based on register=1 is derelict.

-- 
Ticket URL: <https://bugs.scummvm.org/ticket/9894#comment:12>
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