DIRECTOR: Correct for invalid loop bounds in D4

[threefins]

In some D4 version 400 (file version 0x45B) files, sound resource loop bounds are invalid but their cast member flags are set to loop. Examples are "Barbie and her Magical Dreamhouse" and "Necrobius" (Windows demo). Invalid is any situation where the following does not hold: loop_start < loop_end <= size

In the original environment, these resources are handled by disabling the looping flag and resetting the loop bounds on the sound resources to 0 -> sample size.

This commit checks for invalid loop bounds and applies roughly the same fix. This fixes the invalid sound looping behaviours present in the aforementioned titles.

[sev-]

This does not conform to our https://wiki.scummvm.org/index.php?title=Code_Formatting_Conventions.

Also, I would do it a bit differently:

if (!audio->hasValidLoopBounds()) {
   if (_cast->_version == kFileVer400) {
      debugC(2, kDebugLoading, "Cor....
      ...
    } else {
      warning("SoundCastMember::load(): invalid loop bounds detected");
    }
}

e.g. the idea is to catch the same situation if it happens in other Director versions, so we could test with the original and see what it does. Perhaps, the condition is >= kFileVer400.

If you have possibility to have this movie loaded in the later versions of Director, you could figure it out now.

[threefins]

Yeah - I 'll rework it how you suggest

e.g. the idea is to catch the same situation if it happens in other Director versions, so we could test with the original and see what it does. Perhaps, the condition is >= kFileVer400.

Importing into Windows D4, then re-saving fixes invalid loop bounds :

• sets loop flag to 16 (as in disabling looping)
• Adds valid loop bounds (0->sample length) into the sound resources

It feels to me like it's a migration away from using the sound resource loop bounds to determine looping. Maybe even stop using the soundmanager format for sound resources in later Director Versions ?

I looked through the D4 demos also and found that out of the 200 or so demos and ~11,000 embedded sound cast members, every sound cast member in kFileVer404 movies had valid loop points (start < end <= length). This suggests to me the issue does not need to be corrected at kFileVer404. As such, would it be better to leave it as the existing warning for now?

[threefins]

Numbers from my demo scan here: https://gist.github.com/threefins/fbc02fb1d184a8e06c0bd27bd4d29b07

[sev-]

Thank you for the changes. But for whatever reason, there are quite a lot of incorrect code formatting. Please, refer to https://wiki.scummvm.org/index.php?title=Code_Formatting_Conventions

[sev-]

Thank you