exp10 is a glibc extension, which isn't supported on uClibc. Luckily,
exp10() is trivial to compute based on exp(), so add a wrapper for
the uClibc case.
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>
Instead of mapping the raw volume values linearly to the screen, use
a mapping where the bar height is proportional to the audible volume,
i.e., where the amplitude is the cube of the bar height.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>