Pre-calculate SH coefficients
In VA's spatialization, the function SHRealvaluedBasefunctions
is called once for every sound path.
There might be a performance improvement in pre-calculating the SH coefficients or at least adding constexpr
to the methods.
According to Jonas Schröders BA, these methods have at least some influence on the runtime of a single audio block, especially when increasing the number of paths.
https://git.rwth-aachen.de/ita/ITABase/-/blob/master/src/ITANumericUtils.cpp?ref_type=heads#L531