khodowany
25 lines
779 B
Python
25 lines
779 B
Python
from __future__ import annotations
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from fractions import Fraction
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from typing import NamedTuple
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STANDARD_TUNING = ((6, 40), (5, 45), (4, 50), (3, 55), (2, 59), (1, 64))
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MIN_FRET = 0
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MAX_FRET = 20
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MAX_FRET_SPAN = 4
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WRITTEN_GUITAR_OCTAVE_OFFSET = 12
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class TabPosition(NamedTuple):
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string_number: int
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fret: int
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midi: int
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def within_fret_span(positions) -> bool:
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fretted = [position.fret for position in positions if position.fret > 0]
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return not fretted or max(fretted) - min(fretted) <= MAX_FRET_SPAN
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def positions_for_pitch(midi: Fraction) -> tuple[TabPosition, ...]:
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if midi.denominator != 1:
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return ()
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return tuple(TabPosition(string, int(midi - open_midi), int(midi)) for string, open_midi in STANDARD_TUNING if MIN_FRET <= midi - open_midi <= MAX_FRET)
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