def rapids(chord, time, instrument):
"""
Rapids event generator.
Returns an odot bundle for the rapids engine. API:
/engine : "rapids"
/instrument : (string) -- instrument used
/samples : (list) -- a list of samples for polybuffer~
/suffix : (string) -- filename suffix
/time : (float) -- total time in seconds
/events : (list of bundles) -- bundles containing all of the
information to play back a list of samples, rapidly.
"""
# Figure out event times and update time if necessary:
event_times, time = rapids_time(chord, time)
# Figure out useful articulation categories:
categories = []
for pitch in chord:
categories.append(filterCategories(pitch, instrument, autocat[instrument]))
# create a dictionary of sound queries to be resolved by getSamples:
soundqueries = [{'pitch' : elem[0], 'artic': elem[1]} for elem in collect(chord, categories)
if not(not elem[1])] # discard impossible notes (empty category)
# execute the query, giving us the samples we'd need:
seqfiles = [one(getSamples(sq['pitch'], instrument, sq['artic'])) for sq in soundqueries]
print('-' * 100)
print(len(soundqueries) == len(seqfiles))
print('-' * 100)
# determine transposition ratios for sample playback:
#correct = [pitch - ratio(sample['midi']) for sample in seqfiles]
correct = [ratio(pair[0]['pitch'] - pair[1]['midi']) for pair in collect(soundqueries, seqfiles)]
# filter redundant files:
filenames = [e for e in set([sample['files'] for sample in seqfiles])]
# determine the index of sample playback in polybuffer~:
fileindices = [filenames.index(filename) + 1 for filename in [sq['files'] for sq in seqfiles]]
# construct bundle:
oengine = o.message('/engine', 'rapids')
oinstr = o.message('/insturment', instrument)
osamp = o.message('/samples', filenames)
osuffix = o.message('/suffix', '_' + instrument + '_rapids.wav')
otime = o.message('/time', time)
events = []
for index, value in enumerate(fileindices):
opitch = o.message('/pitch', correct[index])
obuffer = o.message('/buffer', instrument + '.rapids.' + str(value))
oeventtime = o.message('/event/time', event_times[index] + 0.02)
events.append(o.bundle(messages = [opitch, obuffer, oeventtime]))
oevents = o.message('/events', events)
return o.bundle(messages = [oengine, oinstr, osamp, osuffix, otime, oevents])
def filterCategories(pitch, instrument, categories):
"""
Returns new list of categories that contain desired pitch.
"""
diffs = [min([abs(pitch - midi)
for midi in SAMPLES[instrument][category]['midi']]) for category in categories]
return [elem[0] for elem in collect(categories, diffs) if elem[1] < 7]
