08-function-calls.py - Using custom algorithms with python function calls. — Pyo 1.0.4 documentation

Pyo 1.0.4 documentation

# 08-function-calls.py - Using custom algorithms with python function calls.

EventCall

    EventCall(function, *args, occurrences=inf, stopEventsWhenDone=True)

EventCall calls a function, with any number of arguments (*args) and uses its return value for the given parameter. The example below use a function from the random module, randrange, with arguments and a user-defined function, without argument, to create a rising, then falling, amplitude curve.

    import random
    from pyo import *

    s = Server().boot()

    db = -30
    dir = 1

    def riseFallAmp():
        "Rises and falls amplitude between -30 and -3 dB, 1 db at the time."
        global db, dir
        db += dir
        if db >= -3:
            dir = -1
        elif db < -30:
            dir = 1
        return db

    # Midi notes are chosen randomly with a function from the random module,
    # while the amplitude change according to the riseFallAmp function's output.
    e = Events(
        midinote=EventCall(random.randrange, 48, 72, 3),
        beat=1 / 4.0,
        db=EventCall(riseFallAmp),
        attack=0.001,
        decay=0.05,
        sustain=0.5,
        release=0.005,
    ).play()

    s.gui(locals())