SCUMM: MI1EGA [CMS audio] CMS music and sound effects dissapear after loading saved game.

[vanfanel]

Hi there,

In Monkey 1 EGA using the CMS Audio system, saving a game while music is playing (for example, inside the Scumm Bar) and the loading the game results on missing music & sfx for the rest of the game.

There was a similar bug with CMS that was fixed time ago, but not the same:

https://bugs.scummvm.org/ticket/10696

[antoniou79]

I can partially confirm this, on Windows 10 with current dev build from master HEAD.

The music stops when reloading a game (which was saved in a room with music, eg. the Scumm Bar). However:

• If you load the game from the ScummVM launcher (so exit the game to the launcher, then load a game from the launcher), the sfx will still play, and the room will have music the next time you visit it -- also all other music still plays.
• If you load the game while in-game, you get the bugged behavior - no music and no sfx anymore.

Can you verify that this is the case for you too?

My guess as of yet is that something is not initialized, or more specifically not clean-up properly, when loading a game while the game is running. I'll have to look further into this.

[athrxx]

Did you start the game with CMS sound from the beginning? Or did you change the sound setting later?

Unfortunately, savegames with different sound settings are often not compatible. This is especially true for MI1 when using CMS sound (the AdLib and Midi setting will put a data block of ~2.5 KB into the savegame, the CMS setting does not save a state at all, so switching between the settings is likely to cause major issues). I would like to fix this eventually (at least for future savegames), but we needn't mix this into your bug ticket if it isn't the actual cause of your problem...

[athrxx]

Okay, after a quick debug session I found and fixed one bug that is probably related to this ticket ("missing music & sfx for the rest of the game"). CMS sound resources basically got invalidated after one use, so they were lost even when reloading a game (but indeed you'd get them back if reloading from the ScummVM launcher).

Another thing that I have not addressed is the restoration of sounds that were playing at the time of saving. I have to check if the original MI1 interpreter does that for CMS (probably yes). Since this would require to save the sound info into the savegame, it might make sense to fix it together with the incompatibility issue we have.

[antoniou79]

From my side, I can verify that the fix works to address the missing sounds and music after re-loading in-game, as long as you revisit the room with the music that is.

[eriktorbjorn]

Replying to athrxx:

Unfortunately, savegames with different sound settings are often not compatible. This is especially true for MI1 when using CMS sound (the AdLib and Midi setting will put a data block of ~2.5 KB into the savegame, the CMS setting does not save a state at all, so switching between the settings is likely to cause major issues). I would like to fix this eventually (at least for future savegames), but we needn't mix this into your bug ticket if it isn't the actual cause of your problem...

If you do manage to fix savegame incompatibility you can probably close https://bugs.scummvm.org/ticket/2693 as well, and wouldn't that be nice? :-)

[sev-]

Now we check the sound drivers on savegame load and request the user to switch to the matching driver.

So, this is considered to be fixed. E.g. it is not possible to fix it, as the different sound cards have different script execution paths, but at least now we are warning the user about the problem instead of just stopping the music.