Multi-Part Music
================

*Example script* (scamp): `examples/Tutorial/10_multi_part.py <https://github.com/MarcTheSpark/scamp/blob/main/examples/Tutorial/10_multi_part.py>`__

*Download:* :download:`10_multi_part.py <downloads/tutorial_10_multi_part/10_multi_part.py>`

Plays two coordinated but independent parallel parts, one for oboe and one for bassoon.

*Topics:* :doc:`Time & clocks › Forking & simultaneity <time_clocks>`

.. raw:: html

   <div style="border:1px solid #ccc;padding:8px;margin:0.2em 0 0.6em;display:inline-block;max-width:100%"><img src="../_static/media/Tutorial/10_multi_part.svg" alt="score" style="max-width:100%;height:auto;display:block"></div>

.. raw:: html

   <div style="margin:0.6em 0"><audio controls preload="none" src="../_static/media/Tutorial/10_multi_part.mp3" style="width:100%;max-width:520px"></audio></div>

.. code-block:: python

   from scamp import *
   import random

   # one way of setting an initial tempo
   s = Session(tempo=100)

   oboe = s.new_part("oboe")
   bassoon = s.new_part("bassoon")


   # define a function for the oboe part
   def oboe_part():
       # play random notes until we have
       # passed beat 7 in the session
       while s.beat < 7:
           pitch = int(random.uniform(67, 79))
           volume = random.uniform(0.5, 1)
           length = random.uniform(0.25, 1)
           oboe.play_note(pitch, volume, length)
       # end with a note of exactly the right
       # length to take us to the end of beat 8
       oboe.play_note(80, 1.0, 8 - s.beat)


   # define a function for the bassoon part
   def bassoon_part():
       # simply play quarter notes on random
       # pitches for 8 beats
       while s.beat < 8:
           bassoon.play_note(
               random.randint(52, 59), 1, 1
           )


   s.start_transcribing()
   # start the oboe and bassoon parts as two parallel child processes
   s.fork(oboe_part)
   s.fork(bassoon_part)
   # have the session wait for the child processes to finish (return)
   s.wait_for_children_to_finish()
   performance = s.stop_transcribing()
   performance.to_score().show()