I'm not saying sample-accurate, because it turns out, Fluidsynth has an internal buffer size and thus timing granularity of 64 frames. So 64 frames is the max. accuracy attainable for SF2. But it's better than nothing. Big thanks to David Henningsson of the Fluidsynth dev team, who very helpfully answered questions. A great guy.
In addition, there are some fixes to earlier commits here, which I ran into while working on the SF2 timing.
Change in handling of frameoffset for multistreamed instruments and sampletracks.
- Instead of holding the offset for the lifetime of the playhandle, negate the offset in the first period
- Multistream-instruments require some small changes: they have to now check for the offset and accordingly leave empty space in the start of the period (already done in this commit)
- There are possibly optimizations that can be done later
- This change is necessary so that we can have sample-exact models, and sample-exact vol/pan knobs for all instruments. Earlier multistream instruments were always rendering some frames ahead-of-time, so applying sample-exact data for them would have been impossible, since we don't have the future-values yet...
Since we now provide the wavetables as pre-generated files, there's no delay caused by their initialization
so we can move it to the startup of the software. I thought engine.cpp is the best place for this, it makes
conceptually more sense than main.cpp IMO.
This way each instrument that wants to use them in the future won't have to call the initialization function
separately, making things a bit easier.
