Computer Keyboard Input
=======================

*Example script* (scamp): `examples/Tutorial/26_keyboard_input.py <https://github.com/MarcTheSpark/scamp/blob/main/examples/Tutorial/26_keyboard_input.py>`__

*Download:* :download:`26_keyboard_input.py <downloads/tutorial_26_keyboard_input/26_keyboard_input.py>`

(WARNING: consumes key events and makes the keyboard otherwise unresponsive. To avoid this, you can remove the suppress=True flag under register_keyboard_listener) Demonstration of receiving computer keyboard events and using them to play notes based on the key number. Any key whose number code lies within a reasonable range triggers the playback of a note of that MIDI pitch.

*Topics:* :doc:`Interactivity & visualization › Keyboard input <interactivity_visualization>`

.. raw:: html

   <iframe src="https://www.youtube-nocookie.com/embed/UtSBJ9rk5yw" style="width:100%;max-width:640px;aspect-ratio:16/9;border:0;display:block;margin:0.6em 0" allowfullscreen></iframe>

.. code-block:: python

   from scamp import *

   s = Session()

   piano = s.new_part("piano")

   # dictionary mapping keys that are down to the NoteHandles used to manipulate them.
   notes_started = {}


   def key_down(name, number):
       if 20 < number < 110 and number not in notes_started:
           notes_started[number] = piano.start_note(number, 0.5)


   def key_up(name, number):
       if 20 < number < 110 and number in notes_started:
           notes_started[number].end()
           del notes_started[number]


   # note: suppress=True causes keyboard events to be consumed by this script, effectively disabling the keyboard
   s.register_keyboard_listener(on_press=key_down, on_release=key_up, suppress=True)
   s.wait_forever()