About dmg_audio_sync branch

[copyrat90]

dmg_audio_sync branch lets you synchronize PSG music (bn::dmg_music) along with PCM music (bn::music).

Preparing music

Check out the README.md in the advgm examples/sync_with_maxmod

Integration

After checking out dmg_audio_sync branch, you need to add this to your project's Makefile:

# DMGAUDIOSYNC enables synchronization of audio and DMG audio playback when it is not empty.
#     Keep in mind that you can't use link cable features with this enabled.
DMGAUDIOSYNC	:=  true

I recommend to also set USERFLAGS := -DBN_CFG_AUDIO_MIXING_RATE=BN_AUDIO_MIXING_RATE_31_KHZ for better PCM music quality.

After that, you can access the newly added bn::synced_music APIs.
Check out the examples/synced_audio for its usage.

One thing you can easily miss is that the default PSG master volume is set to QUARTER.
Most of the time you would want to set it to FULL:

bn::dmg_music::set_master_volume(bn::dmg_music_master_volume::FULL);