class Music:
"""A music class is a notes object populated from an on disk midi file.
self.notes is a list of all the notes in the file for rendering and scoring
self.keys is a dictionary keyed by note number to keep track on note on and note off events."""
def __init__(self, graphics: Graphics, note_render: NoteRender,
staff: Staff):
self.graphics = graphics
self.staff = staff
self.note_positions = staff.get_note_positions()
self.notes = Notes(graphics, note_render, staff, self.note_positions)
self.song = None
self.tempo_bpm = 60
self.ticks_per_beat = Song.SDQNotesPerBeat
self.backing_index = {}
self.backing_time = {}
def load(self, song: Song):
""" Post-process the raw note data of the music, adding rests and decoration"""
self.reset()
self.song = song
self.tempo_bpm = song.tempo_bpm
self.ticks_per_beat = song.ticks_per_beat
for id in self.song.backing_tracks:
self.backing_index[id] = 0
self.backing_time[id] = 0.0
self.staff.key_signature.set(song.key_signature, self.note_positions)
self.notes.assign_notes(song.notes)
def rewind(self):
"""Restore all the notes and backing in the music to the state just after loading."""
self.notes.rewind()
self.backing_index = {track: 0 for track in self.backing_index}
self.backing_time = {track: 0.0 for track in self.backing_time}
def reset(self):
self.notes.reset()
self.backing_index = {}
self.backing_time = {}
def update(self, dt: float, music_time: float, devices: MidiDevices):
"""Play MIDI messages that are not for interactive scoring by the player."""
music_time_in_ticks = (music_time /
Song.SDQNotesPerBeat) * self.ticks_per_beat
def update_backing_track(id: int, ticks_time: float):
b_len = len(self.song.backing_tracks[id])
b_index = self.backing_index[id]
b_time = self.backing_time[id]
if b_len == 0 or b_index >= b_len:
return
next_event = self.song.backing_tracks[id][b_index]
while b_time <= ticks_time:
if devices.output_port:
devices.output_port.send(next_event)
self.backing_index[id] += 1
b_index = self.backing_index[id]
if b_index >= b_len:
break
next_event = self.song.backing_tracks[id][b_index]
self.backing_time[id] += next_event.time
b_time = self.backing_time[id]
for _, id in enumerate(self.song.backing_tracks):
update_backing_track(id, music_time_in_ticks)
def draw(self, dt: float, music_time: float, note_width: float) -> dict:
"""Draw any parts of the scene that involve musical notation."""
return self.notes.draw(dt, music_time, note_width)
