COMI: Crash in ship-to-ship combat

Savegame before the first ship-to-ship combat

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Hm, does it also crash with 0.11.0? What about 0.10 ?

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Well, 0.11.0 produces the same error when using the same savegame, but perhaps that's not surprising. I'd have to replay the first half of the game with 0.10 and 0.11 to say for sure. (I tried it with boot params, but I can't even repeat the crash with the SVN version then.)

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Though the offset doesn't match, I think this is the part of room-39-2011 that triggers the crash:

[039C] (65) if (array395[var391][1] == 99) {
[03B7] (67) breakHere()
[03B8] (79) startScript(0,300,[])
[03C8] (66) } else {
[03CD] (7D) jumpToScript(0,256,[1,localvar4])
[03E7] (**) }

The var391 variable is set to a number from one through 8 just before. I think these numbers represent the various ships, with 7 being Rottingham's ship. (Perhaps 8 is the glass-bottom boat I've heard can appear as an easter egg?)

I added a debug printf() to ScummEngine_v6::readArray(). Oddly enough, if I attack Rottingham's ship immediately, FROM_LE_16(ah->dim1) is 9 and FROM_LE_16(ah->dim2) is 6. If I attack another ship first, these dimensions are swapped to 6 9.

Oddly enough, as soon as I load the savegame, ScummEngine_v6::defineArray() sets the array's dimension to 6 9, which I assume is correct. Something - and I'm still trying to figure out what - then swaps the dimensions to 9 6.

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The "mysterious" change may be simply loading the savegame. So somewhere along the line, something changed the dimensions of the array? Going back to my old savegames, the dimensions were 6 9 before visiting the Voodoo Lady, but 9 6 at some point shortly afterwards. But I haven't been able to reproduce the swapping now.

I don't remember if I was using the trunk or the 0.11 branch at this point, but one of the savegames is dated December 30th, 20:19, and the other December 31 09:32. Oddly enough, the latter savegame claims to have a much shorter playtime, so maybe all this means nothing after all...

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Just one more comment. :-)

It's strange that script-259 changes the dimensions of array 395 to the correct ones, though. It's as if someone anticipated that the dimensions could be changed during gameplay.

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I've played the game all over again, from the beginning. This time, I wasn't able to trigger whatever bug had changed the dimensions of the array, and so I wasn't able to reproduce the crash. I don't know if the bug is invalid or not.

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Well, if we can't reproduce the issue, I am tempted to close this. Who knows what corrupted the original savegame. Not nice, of course :-/

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I guess I have to agree. Even *if* the bug happens again, it seems the scripts correct the array dimensions if you attack any other ship than Rottingham's (I'm still not sure exactly how the ship-to-ship combat works, though, and the click-to-attack-enemy-immediately is strange), so it's not very likely to ever be noticed.