:orphan:

Metric Phase
============

*Example script* (scamp): `examples/Time & clocks/Advanced/metric_phase.py <https://github.com/MarcTheSpark/scamp/blob/main/examples/Time & clocks/Advanced/metric_phase.py>`__

*Download:* :download:`metric_phase.py <downloads/time_clocks_advanced_metric_phase/metric_phase.py>`

Rate targets aligned to metric phase, so accelerations and decelerations land on downbeats.

*Topics:* :doc:`Time & clocks › Advanced <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/Time%20%26%20clocks/Advanced/metric_phase.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/Time%20%26%20clocks/Advanced/metric_phase.mp3" style="width:100%;max-width:520px"></audio></div>

.. code-block:: python

   from scamp import *

   s = Session(tempo=120)

   piano = s.new_part("piano")
   metronome = s.new_part("woodblock")

   def metro():
       while True:
           metronome.play_note(90, 1.0, 1)
           metronome.play_note(85, 1.0, 1)
           metronome.play_note(85, 1.0, 1)

   def chromatic_accel():
       set_rate_target(2, Moment.after_beats(8), align_to=Moment.after_time(6))
       for p in range(48, 80):
           piano.play_note(p, 1, 0.25)
       print(current_clock().beat, current_clock().time)
       for _ in range(12):
           piano.play_note(80, 1, 0.5)
           piano.play_note(75, 1, 0.5)
       set_rate_target(1, Moment.after_beats(8), align_to=Moment.after_time(6))
       for p in range(80, 48, -1):
           piano.play_note(p, 1, 0.25)
       for _ in range(6):
           piano.play_note(48, 1, 0.5)
           piano.play_note(43, 1, 0.5)
       set_rate_targets([3, 0.5, 2, 1], [Moment.after_beats(8), Moment.after_beats(15), Moment.after_beats(18), Moment.after_beats(21)], align_to=MetricPhaseTarget(0, 3))
       print(current_clock().beat)
       for _ in range(7):
           for i in range(12):
               piano.play_note(60 + i, 1, 0.25)
       print(current_clock().beat)
       for _ in range(10):
           piano.play_note(72, 1, 0.5)


   s.start_transcribing()
   accel_clock = fork(chromatic_accel)
   metro_clock = fork(metro)
   # Let the metronome run until the chromatic accel line is done, then cut it off.
   wait_for_clock_to_finish(accel_clock)
   metro_clock.kill()
   s.stop_transcribing().to_score(time_signature="3/4").show()