* audout: Implement GetAudioOutBufferCount, GetAudioOutPlayedSampleCount and FlushAudioOutBuffers
This PR implement audout service calls:
- GetAudioOutBufferCount
- GetAudioOutPlayedSampleCount
- FlushAudioOutBuffers
The RE calls just give some hints about no extra checks.
Since we use a totally different implementation because of our backend, I can't do something better for now.
SetAudioOutVolume and GetAudioOutVolume are fixed too by set/get the volume of the current opened track, previous implementation was wrong.
This fix#1133, fix#1258 and fix#1519.
Thanks to @jduncanator for this help during the implementation and all his precious advices.
* Fix some debug leftovers
* Address jD feedback
Changes:
Implement software surround downmixing (fix#796).
Fix a crash when no audio renderer were created when stopping emulation.
NOTE: This PR also disable support of 5.1 surround on the OpenAL backend as we cannot detect if the hardware directly support it. (the downmixing applied by OpenAL on Windows is terribly slow)
* audout:u: Implement SetAudioOutVolume and GetAudioOutVolume
- Implementation of `audout:u` SetAudioOutVolume and GetAudioOutVolume (checked with RE).
- Add Get and Set for Volume into audio backends.
- Cleanup of all audio backends to follow the `IAalOutput` structure and .NET standard.
- Split OpenAL backend into 2 files for consistency.
* Address comments
* Fix the volume calculation
