music volume also affects "normal" sound volume

[neogeographica]

As expected, changing the "volume" console variable changes only the sound effects volume, and leaves the music volume unchanged.

However, changing the "bgmvolume" variable affects BOTH the normal sound effects and the music volume. So it's impossible to turn down the music while still keeping the normal sound effects.

This is on Windows 7, using fmod375.dll for the fmod library.

[neogeographica]

A few notes about this:

• Playing a music track in Music_PlaySound uses FSOUND_FREE as the channel, which means "use any available channel".
• Changing the bgmvolume cvar runs a callback OnChange_bgmvolume. That calls Music_ChangeVolume, which calls qFSOUND_SetSFXMasterVolume.
• SetSFXMasterVolume apparently sets the volume for all channels. It's a little funny that this is documented as specifically for SFX and NOT for music, but maybe we're basically playing our music track as SFX. Anyway, the effects do cover whatever channel is selected for playing music.
• But it looks like SetSFXMasterVolume will also affect all the other channels of the current sound device, i.e. including the channels that we're not using through fmod (for music) but are using through DirectSound (for sound effects).

I don't know the first thing about fmod or DirectSound. However, I did dig up some fmod 3 API docs at http://delok.free.fr/Boulot1/RM'X%20Vibration/FMOD/fmod361html/HTML/FSOUND.html . Just spitballing some ideas:

If we knew what channel we could use for the music we could maybe use SetVolume or SetVolumeAbsolute to just set the volume for that channel, and avoid using SetSFXMasterVolume.

There's a lot of different code for setting the # of channels which I haven't fully looked at yet. For Windows it seems to always be 2 channels but snd_linux.c is apparently more flexible about setting the # of channels, accepting some arbitrary number if specified through an environment variable. That makes it difficult to reserve a specific "high channel" for music tracks, especially without knowing what the device might actually support. Couple of options there:

• Reserve channel 0 for music tracks and shift the sound effects tracks up by one.
• Still use FSOUND_FREE the first time when playing a music track through Stream_Play. This is supposed to return the selected channel, so remember and keep re-using that channel.

[neogeographica]

Welp, I tried the second approach above, and even when we only do SetVolumeAbsolute on the specific channel where the fmod music is playing, the DirectSound sound effects are still affected.

BTW the channel selected when using FSOUND_FREE (for playing the music stream) seems always be channel 0. I believe this is going to be a "software channel" as far as fmod is concerned. Since fmod is a DirectSound wrapper (I think?) on Windows, I guess it's not super-surprising that any fmod volume manipulations are stomping on the sound effects that are being handled "directly" through DirectSound.

But I could just be completely talking through my hat and an actual sound-savvy developer would know better what is going on.

[SpiritQuaddicted]

Weird, this works perfectly well on Linux (with "FMOD v3.75 initialized").

I wish for someone to switch sound (and other things) over to SDL, then probably https://github.com/SpiritQuaddicted/reQuiem/issues/3 and https://github.com/SpiritQuaddicted/reQuiem/issues/2 would solve itself too. I tried convincing someone but failed. Maybe something for https://github.com/ericwa ? ;)

I uploaded the original dll files from jdhack to http://chunk.io/f/dd7636ba5d7b464880f20abdb4dd9fed for the distant chance that it works with them.

[neogeographica]

Nope! Same fmod DLL there, same result.

[SpiritQuaddicted]

It works fine for me on Windows 7 and some onboard Realtek HD audio thing.

[neogeographica]

I've tried this on a couple of different Win7 systems, and I've noticed a couple of things:

• A nonzero bgmvolume affects the overall sound effects volume (as well as the music volume).
• If I set bgmvolume to 0, it also completely turns off sound effects for the current session. However, if I restart reQuiem, I get the sound effects back (and no music). There's probably some shortcut at startup that avoids applying bgmvolume if it is 0.

In your experiments, were you changing bgmvolume while reQuiem was running, or changing it outside the game (editing the config)? And were you setting it to zero or to some nonzero value?