Since this gets used by both the sound backend and the music code it needs to be in a place accessible to both.
# Conflicts:
# src/CMakeLists.txt
# Conflicts:
# libraries/zmusic/decoder/mpg123_decoder.cpp
# libraries/zmusic/decoder/sndfile_decoder.cpp
# src/CMakeLists.txt
Also made the decode_vorbis function in DUMB a function pointer so that the library does not depend on high level code and can just ignore the vorbis case if no supported.
There's really no need for a non-standard solution here anymore with C++11.
This also fixes an unreleased lock in the WildMidi code.
# Conflicts:
# src/posix/sdl/critsec.cpp
src\sound\musicformats\music_libsndfile.cpp(119): warning C4267: 'argument': conversion from 'size_t' to 'long', possible loss of data
src\sound\musicformats\music_libsndfile.cpp(139): warning C4267: 'argument': conversion from 'size_t' to 'long', possible loss of data
src\sound\musicformats\music_libsndfile.cpp(145): warning C4267: 'argument': conversion from 'size_t' to 'long', possible loss of data
src\sound\musicformats\music_libsndfile.cpp(167): warning C4800: 'int': forcing value to bool 'true' or 'false' (performance warning)
src\sound\musicformats\music_libsndfile.cpp(178): warning C4267: 'argument': conversion from 'size_t' to 'long', possible loss of data
src\sound\musicformats\music_libsndfile.cpp(240): warning C4267: 'argument': conversion from 'size_t' to 'long', possible loss of data
Use snd_streambuffersize CVAR to set buffer size in kilobytes, from 16 to 1024
Name of existed CVAR from removed FMOD sound backend is used
Increased default size of stream buffer to 64 kB like it was in FMOD backend
This is somewhat brute-force thanks to the surprising lack of good documentation for the Ogg headers. The only other option would have been some rather bloated library for a function that should be 25-30 lines at most.
The idea is to have more control on the game side instead of dealing with these formats in the backend, which was done for FMod because it already had the decoders implemented.
However, with OpenAL this setup makes no sense and only complicates future extensions that can be better handled at a higher level.
