On Sun, Nov 14, 2010 at 12:00 PM, Mathieu Bouchard matju@artengine.cawrote:
Why does it do that in the application instead of inside some daemon ? I mean, what if you run 3 sound apps at once, does it does the same transformation on three signals (or pairs of signals) before mixing them ?
Since I don't work at Apple I don't have the definitive answer to that.
In a standard Shark trace time spent in drivers is charged to the userland app that initiates the calls. The DSP could very well be doing those transforms only once, but if Pd is the only app accessing the driver, the functions would only be in the Pd trace. The GPU driver work from the GL calls in GEM show up under Pd's process too.
Fire up ITunes and see what happens to audio in the driver.