quartz: add implementations for AmpFactorToDB and DBToAmpFactor

[Alexandre Julliard]

Robert Reif <reif at earthlink.net> writes:

> For whatever reason Microsoft decided not to use the standard
> equations like the rest of the world.  I assume it was to eliminate
> the need for floating point calculations.  Actually you could use the
> same equation that the generated the table to go from dB to amp but
> you can't use an equation to go the other way around because of the
> weird roundoff errors that result from using a lookup table.

Yes, but does that really make a difference for real apps?  Do we
really need to duplicate the roundoff errors?

-- 
Alexandre Julliard
julliard at winehq.org