SCI: GK1 Floppy lockup after phone rings on day 5

[Mesandro]

Scumm Version: 2.9.0 Universal Apple
Version of game: 1.0/1.0b (Floppy) 1.0a (CD)
System: MacOS Sequoia 15.4 on two different machine (Macbook and imac)

Hi guys, I'm going to report a couple of problems I encountered while playing Gabriel Knight Sins of the Fathers.

I would like to point out that I use the standard versions of the games but that trying to install the NRS patches did not solve the problem anyway.

The first concerns the famous bug of day 5 that blocks the game: I noticed that on the CD version everything works perfectly (so I think it is solved by scumm) while on my floppy version everything was useless. I have always encountered the problem. I solved it only by accelerating the game speed from the setting by loading a previous save and changing it before the problem appeared. I read that the compatibility is excellent for this game, am I doing something wrong? What is the procedure to avoid this bug on scumm?

The second problem concerns the audio of the DOS version on CD. I tested the game on two different computers to make sure it was not my problem and in fact it appears in both cases. Basically, using the game with the voices turned off (so only text) and turning up the volume, in some parts of the game (like the voodoo museum, or Mosely's office) during the text dialogues with every click of the mouse you hear low and random midi sounds that create a lot of annoyance in some cases because they overlap with the music. For example, if you talk to Dr. John in the museum, with every sentence you click these sounds appear. I use all the default settings, but even changing options related to audio or MIDI, does not solve the problem. Now I do not know if this defect also occurs when playing the game natively on a DOS PC, but I wanted to report it. This problem does not appear in the Floppy version and only concerns the CD version (DOS).

Thanks

[m-kiewitz]

Hi,
There are multiple bugs on day 5. Can you please tell us which bug you are talking about?
There also were some timer issue script patches originally, but they were removed because the speed throttler should catch them all.
I don't think that I own the floppy version of GK1, I can't check that version myself.

[Mesandro]

Replying to m-kiewitz:

Hi,
There are multiple bugs on day 5. Can you please tell us which bug you are talking about?
There also were some timer issue script patches originally, but they were removed because the speed throttler should catch them all.
I don't think that I own the floppy version of GK1, I can't check that version myself.

I am referring to the bug that appears at the beginning of Day 5 just after the phone rings, causing Gabriel to freeze and leaving the "GK" shield on the screen. I have tried reproducing this bug in several ways and it has never disappeared. I first tried with the standard version on floppy (1.0) and it happened, then I updated the game with the official patch that brings it to version 1.0b and it behaves exactly the same way. Finally I tried the scripts you mentioned (known as NRS patches) and even in this case the bug persists. The bug only disappears if you set a high game speed in the settings before it appears. This does not happen on the DOS CD version which works perfectly at any game speed set.

[m-kiewitz]

No, the patches I was talking about are the patches inside of ScummVM.
We are patching games automatically, without changing script files and in a dynamic way, so that in most cases localized game versions are getting patched the same way, without us having to create special patches for every game version.

ScummVM does not need these external patches, and you should not use them. They will also not work for localized versions of the game, and in some cases also break saved game compatibility, in other cases even introduce new bugs.

Maybe another ScummVM-SCI developer owns the floppy version of Gabriel Knight 1 and can look into this. I'm pretty sure there were localized floppy versions too.

[Mesandro]

Replying to m-kiewitz:

No, the patches I was talking about are the patches inside of ScummVM.
We are patching games automatically, without changing script files and in a dynamic way, so that in most cases localized game versions are getting patched the same way, without us having to create special patches for every game version.

ScummVM does not need these external patches, and you should not use them. They will also not work for localized versions of the game, and in some cases also break saved game compatibility, in other cases even introduce new bugs.

Maybe another ScummVM-SCI developer owns the floppy version of Gabriel Knight 1 and can look into this. I'm pretty sure there were localized floppy versions too.

Very clear, thank you very much for the info. I had already imagined that those patches were not useful in ScummVM, but since for the CD version the files in the "Patches" folder are considered anyway, I wanted to try but in this case without success. Regarding the midi sounds on the CD version instead I wanted to report it, but I think it is a normal behavior of the game (which is annoying anyway), since it also appears on windows 10 (in addition to mac os).

[m-kiewitz]

Sierra had some patches too, those are indeed useful, but that's official patches made by Sierra.
I think we still implemented some smaller official fixes made by Sierra into ScummVM, so that users do not even have to use these official Sierra patch downloads.

Not fan made patches using fan tools, which as I said sometimes introduce additional bugs or don't solve the bugs properly.

ScummVM also supports different platforms, for example Japanese PC-98, FM Towns and Macintosh versions. Same problem there, because some of these Non-DOS platforms use different scripts, and if you use these fan patches for these game versions, they may also break, meanwhile the generic game patches under ScummVM should patch bugs common on all the different platforms, even when the byte order is different.

I'm not sure about Midi. Our current code is reusing generic ScummVM code, and that's not really perfectly accurate, because SCI did not work like most other game engines in regards of seeking inside the music track.
It would be great if you could try this out under plain DOS, so that we can make sure that it's not a game issue, but an issue with ScummVM. We can in theory fix both of these, but we need to know which is which, at least for documentation purposes.

[Mesandro]

Replying to m-kiewitz:

Sierra had some patches too, those are indeed useful, but that's official patches made by Sierra.
I think we still implemented some smaller official fixes made by Sierra into ScummVM, so that users do not even have to use these official Sierra patch downloads.

Not fan made patches using fan tools, which as I said sometimes introduce additional bugs or don't solve the bugs properly.

ScummVM also supports different platforms, for example Japanese PC-98, FM Towns and Macintosh versions. Same problem there, because some of these Non-DOS platforms use different scripts, and if you use these fan patches for these game versions, they may also break, meanwhile the generic game patches under ScummVM should patch bugs common on all the different platforms, even when the byte order is different.

I'm not sure about Midi. Our current code is reusing generic ScummVM code, and that's not really perfectly accurate, because SCI did not work like most other game engines in regards of seeking inside the music track.
It would be great if you could try this out under plain DOS, so that we can make sure that it's not a game issue, but an issue with ScummVM. We can in theory fix both of these, but we need to know which is which, at least for documentation purposes.

Exactly, in fact I wanted to specifically test the original versions using only official patches (with the exception of the NRS patch that I described before that didn't work anyway). However, apart from the block on day 5, I played the floppy version without any other problems until the end. As for the midi issue, in the end it's a small problem that doesn't affect playability but is still present in the CD version. This makes me understand that it is strictly linked to the audio files of the CD version since the problem doesn't exist on floppy. Unfortunately, I don't have the possibility to test the game under native DOS, otherwise I would have gladly cleared up this doubt...

[sluicebox]

Hello! Thank you for reporting this. I can reproduce the day 5 lockup using a floppy version and turning the game speed down to very low at the end of day 4 before triggering the next-day transition.

Reproducing these things is half the battle, so I'll take a deeper look soon and we'll get to the bottom of it. Although the day 5 lockup is infamous, this is the first time I've ever seen it.

[Mesandro]

Replying to sluicebox:

Hello! Thank you for reporting this. I can reproduce the day 5 lockup using a floppy version and turning the game speed down to very low at the end of day 4 before triggering the next-day transition.

Reproducing these things is half the battle, so I'll take a deeper look soon and we'll get to the bottom of it. Although the day 5 lockup is infamous, this is the first time I've ever seen it.

Thank you for the work you do on this project. If you need any more information about it, let me know!

[sluicebox <22204938+sluicebox@…>]

In 48c95e37:

SCI32: Fix GK1 day 5 phone lockup in all game versions

Fixes bug #15857

[sluicebox]

Fixed in 48c95e3797d058dd19d9507044eb0e295eac766b

I believe this is the first time this script bug has ever been fully understood and fixed.

Our previous script patch used the NRS technique (change the 3 cycle delay to a 6 tick delay), but that doesn't work on floppy versions at certain game speed settings.

Here In The Future, we have the tools to figure out the underlying script conflict, so I fixed that instead. The new patch does not alter delays or depend on any timing. This should fix all versions, and it's compatible with NRS patches.

I'm closing this ticket as fixed, but you can create a new one with just the sound stuff if you want. Feel free to copy and paste, it's just that it gets confusing if different issues are mixed together.

Thanks again for reporting!

[sluicebox <22204938+sluicebox@…>]

In 24c2a1a2:

SCI32: Fix GK1 day 5 phone lockup in all game versions

Fixes bug #15857