[ scummvm-Patches-672313 ] CMI: Hack for "I can't reach that" (experimental)

[SourceForge.net]

Patches item #672313, was opened at 2003-01-22 09:01
You can respond by visiting: 
https://sourceforge.net/tracker/?func=detail&atid=418822&aid=672313&group_id=37116

Category: None
Group: None
Status: Open
Resolution: None
Priority: 5
Submitted By: Torbjörn Andersson (eriktorbjorn)
Assigned to: Nobody/Anonymous (nobody)
Summary: CMI: Hack for "I can't reach that" (experimental)

Initial Comment:
This patch will need more testing than I've done, but
it's an attempt to fix the problem where Guybrush can't
reach the cannon after Wally stops using it.

What seems to be happening is that a number of
walkboxes have their kBoxInvisible flag set and
cleared. I guess the purpose of it is to modify
Guybrush's walking behaviour (restrict/unrestrict where
he may go, perhaps?) depending on whether or not Wally
is at the cannon. But it doesn't do anything to change
which walkbox Guybrush is in, so he remains trapped
inside walkbox 4.

This is done by the script script room-9-2000 (which is
invoked from at least from the scripts room-9-2009 and
entry-9). This is what it looks like when descummed:

Script# 2000
[0000] (65) if (0== bitvar167) {
[000B] (A7)   setBoxFlags([5,6,7,8,9,13],128)
[0034] (A7)   setBoxFlags([1,2,3,4],0)
[0053] (A8)   createBoxMatrix()
[0058] (66) } else {
[0054] (A7)   setBoxFlags([1,2,3,4],128)
[0078] (A7)   setBoxFlags([5,6,7,8,9,13],0)
[00A1] (A8)   createBoxMatrix()
[00A2] (**) }
[00A2] (A7) setBoxFlags([10,11,12],128)
[00BC] (7B) stopObjectCode()
END
Stack count: 0

What the patch does is to modify the createBoxMatrix()
opcode for V8 games so that it adjusts the position of
the ego actor. This will move Guybrush from the
invisible walkbox to the equivalent visible walkbox.

I have no idea if this is the right thing to do, but it
does seem to fix the problem so it may be a good place
to start further investigation.

----------------------------------------------------------------------

You can respond by visiting: 
https://sourceforge.net/tracker/?func=detail&atid=418822&aid=672313&group_id=37116