def write_header(self):
# create xi file
self.output_file.write(struct.pack(
'21s22sb20sh',
'Extended Instrument: ',
(self.filename[:-4] + ' ' * 22)[:22], 0x1a, pad_name(VERSION, 20), 0x0
))
self.output_file.write(struct.pack('96b', *(self.notes_samples)))
def write_regions_meta(self):
self.output_file.write(struct.pack('h', len(self.regions))) # number of samples
for region in self.regions:
self.output_file.write(struct.pack(
'i', region['sample_bittype'] * region['sample_length'])) # sample length
self.output_file.write(struct.pack('2i', 0, 0)) # sample loop start and end
# volume
volume = 255
if 'volume' in region:
volume = math.floor(
255 * math.exp(float(region['volume']) / 10) / math.exp(0.6)
) # volume is in dB
self.output_file.write(struct.pack('B', volume))
self.output_file.write(struct.pack('b', int(region['tune']))) # finetune (signed!)
self.output_file.write(struct.pack('b', region['sample_type'])) # sample type
#panning (unsigned!)
pan = 128
if 'pan' in region:
pan = (float(region['pan']) + 100) * 255 / 200
self.output_file.write(struct.pack('B', pan))
key = region['pitch_keycenter'] if 'pitch_keycenter' in region else region['lokey']
self.output_file.write(struct.pack(
'b',
1 - notes.index(key)
+ notes.index('e6')
)) # relative note - transpose c4 ~ 00
sample_name = pad_name(os.path.split(region['sample_path'])[1], 22)
self.output_file.write(struct.pack('b', len(sample_name.strip(' '))))
self.output_file.write(struct.pack('22s', sample_name))