[sdiy] Integer exponential envelope generation

[Olivier Gillet]

The thread was titled "Help with math, please". While there is a
specific formula (just pass a heaviside step through a digital 1 pole
filter -- digitally simulating a RC network) for the exponential case,
Tom Wiltshire suggested doing an interpolated lookup in an
"exponential response" table. I'd recommend that too, since it allows
very easily switching from one response curve to the other ; and this
allows the response to be tweaked into interesting (and very natural
sounding) functions between linear and exponential...

Olivier