Transpose

generator/arrange/fretboard.py

@@ -1,26 +1,18 @@
 from __future__ import annotations
 
 from itertools import product
-from typing import NamedTuple
 
 from generator.transposition import mod12
 from generator import harmony
 from generator.model import NATURAL, alteration
-
-STANDARD_TUNING = ((6, 40), (5, 45), (4, 50), (3, 55), (2, 59), (1, 64))
-WRITTEN_GUITAR_OCTAVE_OFFSET = 12
-
-class TabPosition(NamedTuple):
-  string_number: int
-  fret: int
-  midi: int
+from generator.guitar import MAX_FRET, MIN_FRET, STANDARD_TUNING, TabPosition, WRITTEN_GUITAR_OCTAVE_OFFSET, within_fret_span
 
 def chord_pitch_classes(symbol: str | dict) -> tuple[int, ...]:
   return harmony.pitch_classes(harmony.parse_symbol(symbol) if isinstance(symbol, str) else symbol)
 
 def positions_for_string(string_number: int, open_midi: int, pitch_classes: tuple[int, ...]) -> list[TabPosition]:
   result: list[TabPosition] = []
-  for fret in range(0, 13):
+  for fret in range(MIN_FRET, MAX_FRET + 1):
     midi = open_midi + fret
     if mod12(midi) in pitch_classes:
       result.append(TabPosition(string_number, fret, midi))
@@ -63,14 +55,13 @@ def find_playable_voicing(symbol: str | dict) -> list[TabPosition]:
   best: tuple[TabPosition, ...] | None = None
   best_score = 10**9
   for string_set in string_sets:
-    options = [by_string[string_number][:8] for string_number in string_set]
+    options = [by_string[string_number] for string_number in string_set]
     if any(not item for item in options):
       continue
     for candidate in product(*options):
       if bass_pc is not None and min(candidate, key=lambda p: p.midi).midi % 12 != bass_pc:
         continue
-      fretted = [position.fret for position in candidate if position.fret > 0]
-      if fretted and max(fretted) - min(fretted) > 4:
+      if not within_fret_span(candidate):
         continue
       covered = {mod12(position.midi) for position in candidate}
       if not set(pitch_classes).issubset(covered):