UNPKG

vexflow

Version:

A JavaScript library for rendering music notation and guitar tablature

999 lines (744 loc) 51.1 kB
<!DOCTYPE html> <html> <head> <title>music.js</title> <meta http-equiv="content-type" content="text/html; charset=UTF-8"> <link rel="stylesheet" media="all" href="public/stylesheets/normalize.css" /> <link rel="stylesheet" media="all" href="docco.css" /> </head> <body> <div class="container"> <div class="page"> <div class="header"> <h1>music.js</h1> <div class="toc"> <h3>Table of Contents</h3> <ol> <li> <a class="source" href="accidental.html"> accidental.js </a> </li> <li> <a class="source" href="annotation.html"> annotation.js </a> </li> <li> <a class="source" href="articulation.html"> articulation.js </a> </li> <li> <a class="source" href="barnote.html"> barnote.js </a> </li> <li> <a class="source" href="beam.html"> beam.js </a> </li> <li> <a class="source" href="bend.html"> bend.js </a> </li> <li> <a class="source" href="boundingbox.html"> boundingbox.js </a> </li> <li> <a class="source" href="boundingboxcomputation.html"> boundingboxcomputation.js </a> </li> <li> <a class="source" href="canvascontext.html"> canvascontext.js </a> </li> <li> <a class="source" href="clef.html"> clef.js </a> </li> <li> <a class="source" href="clefnote.html"> clefnote.js </a> </li> <li> <a class="source" href="crescendo.html"> crescendo.js </a> </li> <li> <a class="source" href="curve.html"> curve.js </a> </li> <li> <a class="source" href="dot.html"> dot.js </a> </li> <li> <a class="source" href="easyscore.html"> easyscore.js </a> </li> <li> <a class="source" href="element.html"> element.js </a> </li> <li> <a class="source" href="factory.html"> factory.js </a> </li> <li> <a class="source" href="formatter.html"> formatter.js </a> </li> <li> <a class="source" href="fraction.html"> fraction.js </a> </li> <li> <a class="source" href="frethandfinger.html"> frethandfinger.js </a> </li> <li> <a class="source" href="ghostnote.html"> ghostnote.js </a> </li> <li> <a class="source" href="glyph.html"> glyph.js </a> </li> <li> <a class="source" href="glyphnote.html"> glyphnote.js </a> </li> <li> <a class="source" href="gracenote.html"> gracenote.js </a> </li> <li> <a class="source" href="gracenotegroup.html"> gracenotegroup.js </a> </li> <li> <a class="source" href="gracetabnote.html"> gracetabnote.js </a> </li> <li> <a class="source" href="index.html"> index.js </a> </li> <li> <a class="source" href="keymanager.html"> keymanager.js </a> </li> <li> <a class="source" href="keysignature.html"> keysignature.js </a> </li> <li> <a class="source" href="keysignote.html"> keysignote.js </a> </li> <li> <a class="source" href="modifier.html"> modifier.js </a> </li> <li> <a class="source" href="modifiercontext.html"> modifiercontext.js </a> </li> <li> <a class="source" href="multimeasurerest.html"> multimeasurerest.js </a> </li> <li> <a class="source" href="music.html"> music.js </a> </li> <li> <a class="source" href="note.html"> note.js </a> </li> <li> <a class="source" href="notehead.html"> notehead.js </a> </li> <li> <a class="source" href="notesubgroup.html"> notesubgroup.js </a> </li> <li> <a class="source" href="ornament.html"> ornament.js </a> </li> <li> <a class="source" href="parser.html"> parser.js </a> </li> <li> <a class="source" href="pedalmarking.html"> pedalmarking.js </a> </li> <li> <a class="source" href="raphaelcontext.html"> raphaelcontext.js </a> </li> <li> <a class="source" href="registry.html"> registry.js </a> </li> <li> <a class="source" href="renderer.html"> renderer.js </a> </li> <li> <a class="source" href="repeatnote.html"> repeatnote.js </a> </li> <li> <a class="source" href="smufl.html"> smufl.js </a> </li> <li> <a class="source" href="stave.html"> stave.js </a> </li> <li> <a class="source" href="stavebarline.html"> stavebarline.js </a> </li> <li> <a class="source" href="staveconnector.html"> staveconnector.js </a> </li> <li> <a class="source" href="stavehairpin.html"> stavehairpin.js </a> </li> <li> <a class="source" href="staveline.html"> staveline.js </a> </li> <li> <a class="source" href="stavemodifier.html"> stavemodifier.js </a> </li> <li> <a class="source" href="stavenote.html"> stavenote.js </a> </li> <li> <a class="source" href="staverepetition.html"> staverepetition.js </a> </li> <li> <a class="source" href="stavesection.html"> stavesection.js </a> </li> <li> <a class="source" href="stavetempo.html"> stavetempo.js </a> </li> <li> <a class="source" href="stavetext.html"> stavetext.js </a> </li> <li> <a class="source" href="stavetie.html"> stavetie.js </a> </li> <li> <a class="source" href="stavevolta.html"> stavevolta.js </a> </li> <li> <a class="source" href="stem.html"> stem.js </a> </li> <li> <a class="source" href="stemmablenote.html"> stemmablenote.js </a> </li> <li> <a class="source" href="stringnumber.html"> stringnumber.js </a> </li> <li> <a class="source" href="strokes.html"> strokes.js </a> </li> <li> <a class="source" href="svgcontext.html"> svgcontext.js </a> </li> <li> <a class="source" href="system.html"> system.js </a> </li> <li> <a class="source" href="tables.html"> tables.js </a> </li> <li> <a class="source" href="tabnote.html"> tabnote.js </a> </li> <li> <a class="source" href="tabslide.html"> tabslide.js </a> </li> <li> <a class="source" href="tabstave.html"> tabstave.js </a> </li> <li> <a class="source" href="tabtie.html"> tabtie.js </a> </li> <li> <a class="source" href="textbracket.html"> textbracket.js </a> </li> <li> <a class="source" href="textdynamics.html"> textdynamics.js </a> </li> <li> <a class="source" href="textnote.html"> textnote.js </a> </li> <li> <a class="source" href="tickable.html"> tickable.js </a> </li> <li> <a class="source" href="tickcontext.html"> tickcontext.js </a> </li> <li> <a class="source" href="timesignature.html"> timesignature.js </a> </li> <li> <a class="source" href="timesignote.html"> timesignote.js </a> </li> <li> <a class="source" href="tremolo.html"> tremolo.js </a> </li> <li> <a class="source" href="tuning.html"> tuning.js </a> </li> <li> <a class="source" href="tuplet.html"> tuplet.js </a> </li> <li> <a class="source" href="vex.html"> vex.js </a> </li> <li> <a class="source" href="vibrato.html"> vibrato.js </a> </li> <li> <a class="source" href="vibratobracket.html"> vibratobracket.js </a> </li> <li> <a class="source" href="voice.html"> voice.js </a> </li> <li> <a class="source" href="voicegroup.html"> voicegroup.js </a> </li> </ol> </div> </div> <p><a href="http://vexflow.com">VexFlow</a> - Copyright (c) Mohit Muthanna 2010.</p> <h2 id="description">Description</h2> <p>This class implements some standard music theory routines.</p> <div class='highlight'><pre> <span class="hljs-keyword">import</span> { Vex } <span class="hljs-keyword">from</span> <span class="hljs-string">'./vex'</span>; <span class="hljs-keyword">export</span> <span class="hljs-class"><span class="hljs-keyword">class</span> <span class="hljs-title">Music</span> </span>{ <span class="hljs-keyword">static</span> get NUM_TONES() { <span class="hljs-keyword">return</span> <span class="hljs-number">12</span>; } <span class="hljs-keyword">static</span> get roots() { <span class="hljs-keyword">return</span> [<span class="hljs-string">'c'</span>, <span class="hljs-string">'d'</span>, <span class="hljs-string">'e'</span>, <span class="hljs-string">'f'</span>, <span class="hljs-string">'g'</span>, <span class="hljs-string">'a'</span>, <span class="hljs-string">'b'</span>]; } <span class="hljs-keyword">static</span> get root_values() { <span class="hljs-keyword">return</span> [<span class="hljs-number">0</span>, <span class="hljs-number">2</span>, <span class="hljs-number">4</span>, <span class="hljs-number">5</span>, <span class="hljs-number">7</span>, <span class="hljs-number">9</span>, <span class="hljs-number">11</span>]; } <span class="hljs-keyword">static</span> get root_indices() { <span class="hljs-keyword">return</span> { <span class="hljs-string">'c'</span>: <span class="hljs-number">0</span>, <span class="hljs-string">'d'</span>: <span class="hljs-number">1</span>, <span class="hljs-string">'e'</span>: <span class="hljs-number">2</span>, <span class="hljs-string">'f'</span>: <span class="hljs-number">3</span>, <span class="hljs-string">'g'</span>: <span class="hljs-number">4</span>, <span class="hljs-string">'a'</span>: <span class="hljs-number">5</span>, <span class="hljs-string">'b'</span>: <span class="hljs-number">6</span>, }; } <span class="hljs-keyword">static</span> get canonical_notes() { <span class="hljs-keyword">return</span> [ <span class="hljs-string">'c'</span>, <span class="hljs-string">'c#'</span>, <span class="hljs-string">'d'</span>, <span class="hljs-string">'d#'</span>, <span class="hljs-string">'e'</span>, <span class="hljs-string">'f'</span>, <span class="hljs-string">'f#'</span>, <span class="hljs-string">'g'</span>, <span class="hljs-string">'g#'</span>, <span class="hljs-string">'a'</span>, <span class="hljs-string">'a#'</span>, <span class="hljs-string">'b'</span>, ]; } <span class="hljs-keyword">static</span> get diatonic_intervals() { <span class="hljs-keyword">return</span> [ <span class="hljs-string">'unison'</span>, <span class="hljs-string">'m2'</span>, <span class="hljs-string">'M2'</span>, <span class="hljs-string">'m3'</span>, <span class="hljs-string">'M3'</span>, <span class="hljs-string">'p4'</span>, <span class="hljs-string">'dim5'</span>, <span class="hljs-string">'p5'</span>, <span class="hljs-string">'m6'</span>, <span class="hljs-string">'M6'</span>, <span class="hljs-string">'b7'</span>, <span class="hljs-string">'M7'</span>, <span class="hljs-string">'octave'</span>, ]; } <span class="hljs-keyword">static</span> get diatonic_accidentals() { <span class="hljs-keyword">return</span> { <span class="hljs-string">'unison'</span>: { <span class="hljs-attr">note</span>: <span class="hljs-number">0</span>, <span class="hljs-attr">accidental</span>: <span class="hljs-number">0</span> }, <span class="hljs-string">'m2'</span>: { <span class="hljs-attr">note</span>: <span class="hljs-number">1</span>, <span class="hljs-attr">accidental</span>: <span class="hljs-number">-1</span> }, <span class="hljs-string">'M2'</span>: { <span class="hljs-attr">note</span>: <span class="hljs-number">1</span>, <span class="hljs-attr">accidental</span>: <span class="hljs-number">0</span> }, <span class="hljs-string">'m3'</span>: { <span class="hljs-attr">note</span>: <span class="hljs-number">2</span>, <span class="hljs-attr">accidental</span>: <span class="hljs-number">-1</span> }, <span class="hljs-string">'M3'</span>: { <span class="hljs-attr">note</span>: <span class="hljs-number">2</span>, <span class="hljs-attr">accidental</span>: <span class="hljs-number">0</span> }, <span class="hljs-string">'p4'</span>: { <span class="hljs-attr">note</span>: <span class="hljs-number">3</span>, <span class="hljs-attr">accidental</span>: <span class="hljs-number">0</span> }, <span class="hljs-string">'dim5'</span>: { <span class="hljs-attr">note</span>: <span class="hljs-number">4</span>, <span class="hljs-attr">accidental</span>: <span class="hljs-number">-1</span> }, <span class="hljs-string">'p5'</span>: { <span class="hljs-attr">note</span>: <span class="hljs-number">4</span>, <span class="hljs-attr">accidental</span>: <span class="hljs-number">0</span> }, <span class="hljs-string">'m6'</span>: { <span class="hljs-attr">note</span>: <span class="hljs-number">5</span>, <span class="hljs-attr">accidental</span>: <span class="hljs-number">-1</span> }, <span class="hljs-string">'M6'</span>: { <span class="hljs-attr">note</span>: <span class="hljs-number">5</span>, <span class="hljs-attr">accidental</span>: <span class="hljs-number">0</span> }, <span class="hljs-string">'b7'</span>: { <span class="hljs-attr">note</span>: <span class="hljs-number">6</span>, <span class="hljs-attr">accidental</span>: <span class="hljs-number">-1</span> }, <span class="hljs-string">'M7'</span>: { <span class="hljs-attr">note</span>: <span class="hljs-number">6</span>, <span class="hljs-attr">accidental</span>: <span class="hljs-number">0</span> }, <span class="hljs-string">'octave'</span>: { <span class="hljs-attr">note</span>: <span class="hljs-number">7</span>, <span class="hljs-attr">accidental</span>: <span class="hljs-number">0</span> }, }; } <span class="hljs-keyword">static</span> get intervals() { <span class="hljs-keyword">return</span> { <span class="hljs-string">'u'</span>: <span class="hljs-number">0</span>, <span class="hljs-string">'unison'</span>: <span class="hljs-number">0</span>, <span class="hljs-string">'m2'</span>: <span class="hljs-number">1</span>, <span class="hljs-string">'b2'</span>: <span class="hljs-number">1</span>, <span class="hljs-string">'min2'</span>: <span class="hljs-number">1</span>, <span class="hljs-string">'S'</span>: <span class="hljs-number">1</span>, <span class="hljs-string">'H'</span>: <span class="hljs-number">1</span>, <span class="hljs-string">'2'</span>: <span class="hljs-number">2</span>, <span class="hljs-string">'M2'</span>: <span class="hljs-number">2</span>, <span class="hljs-string">'maj2'</span>: <span class="hljs-number">2</span>, <span class="hljs-string">'T'</span>: <span class="hljs-number">2</span>, <span class="hljs-string">'W'</span>: <span class="hljs-number">2</span>, <span class="hljs-string">'m3'</span>: <span class="hljs-number">3</span>, <span class="hljs-string">'b3'</span>: <span class="hljs-number">3</span>, <span class="hljs-string">'min3'</span>: <span class="hljs-number">3</span>, <span class="hljs-string">'M3'</span>: <span class="hljs-number">4</span>, <span class="hljs-string">'3'</span>: <span class="hljs-number">4</span>, <span class="hljs-string">'maj3'</span>: <span class="hljs-number">4</span>, <span class="hljs-string">'4'</span>: <span class="hljs-number">5</span>, <span class="hljs-string">'p4'</span>: <span class="hljs-number">5</span>, <span class="hljs-string">'#4'</span>: <span class="hljs-number">6</span>, <span class="hljs-string">'b5'</span>: <span class="hljs-number">6</span>, <span class="hljs-string">'aug4'</span>: <span class="hljs-number">6</span>, <span class="hljs-string">'dim5'</span>: <span class="hljs-number">6</span>, <span class="hljs-string">'5'</span>: <span class="hljs-number">7</span>, <span class="hljs-string">'p5'</span>: <span class="hljs-number">7</span>, <span class="hljs-string">'#5'</span>: <span class="hljs-number">8</span>, <span class="hljs-string">'b6'</span>: <span class="hljs-number">8</span>, <span class="hljs-string">'aug5'</span>: <span class="hljs-number">8</span>, <span class="hljs-string">'6'</span>: <span class="hljs-number">9</span>, <span class="hljs-string">'M6'</span>: <span class="hljs-number">9</span>, <span class="hljs-string">'maj6'</span>: <span class="hljs-number">9</span>, <span class="hljs-string">'b7'</span>: <span class="hljs-number">10</span>, <span class="hljs-string">'m7'</span>: <span class="hljs-number">10</span>, <span class="hljs-string">'min7'</span>: <span class="hljs-number">10</span>, <span class="hljs-string">'dom7'</span>: <span class="hljs-number">10</span>, <span class="hljs-string">'M7'</span>: <span class="hljs-number">11</span>, <span class="hljs-string">'maj7'</span>: <span class="hljs-number">11</span>, <span class="hljs-string">'8'</span>: <span class="hljs-number">12</span>, <span class="hljs-string">'octave'</span>: <span class="hljs-number">12</span>, }; } <span class="hljs-keyword">static</span> get scales() { <span class="hljs-keyword">return</span> { <span class="hljs-attr">major</span>: [<span class="hljs-number">2</span>, <span class="hljs-number">2</span>, <span class="hljs-number">1</span>, <span class="hljs-number">2</span>, <span class="hljs-number">2</span>, <span class="hljs-number">2</span>, <span class="hljs-number">1</span>], <span class="hljs-attr">dorian</span>: [<span class="hljs-number">2</span>, <span class="hljs-number">1</span>, <span class="hljs-number">2</span>, <span class="hljs-number">2</span>, <span class="hljs-number">2</span>, <span class="hljs-number">1</span>, <span class="hljs-number">2</span>], <span class="hljs-attr">mixolydian</span>: [<span class="hljs-number">2</span>, <span class="hljs-number">2</span>, <span class="hljs-number">1</span>, <span class="hljs-number">2</span>, <span class="hljs-number">2</span>, <span class="hljs-number">1</span>, <span class="hljs-number">2</span>], <span class="hljs-attr">minor</span>: [<span class="hljs-number">2</span>, <span class="hljs-number">1</span>, <span class="hljs-number">2</span>, <span class="hljs-number">2</span>, <span class="hljs-number">1</span>, <span class="hljs-number">2</span>, <span class="hljs-number">2</span>], }; } <span class="hljs-keyword">static</span> get scaleTypes() { <span class="hljs-keyword">return</span> { <span class="hljs-string">'M'</span>: Music.scales.major, <span class="hljs-string">'m'</span>: Music.scales.minor, }; } <span class="hljs-keyword">static</span> get accidentals() { <span class="hljs-keyword">return</span> [<span class="hljs-string">'bb'</span>, <span class="hljs-string">'b'</span>, <span class="hljs-string">'n'</span>, <span class="hljs-string">'#'</span>, <span class="hljs-string">'##'</span>]; } <span class="hljs-keyword">static</span> get noteValues() { <span class="hljs-keyword">return</span> { <span class="hljs-string">'c'</span>: { <span class="hljs-attr">root_index</span>: <span class="hljs-number">0</span>, <span class="hljs-attr">int_val</span>: <span class="hljs-number">0</span> }, <span class="hljs-string">'cn'</span>: { <span class="hljs-attr">root_index</span>: <span class="hljs-number">0</span>, <span class="hljs-attr">int_val</span>: <span class="hljs-number">0</span> }, <span class="hljs-string">'c#'</span>: { <span class="hljs-attr">root_index</span>: <span class="hljs-number">0</span>, <span class="hljs-attr">int_val</span>: <span class="hljs-number">1</span> }, <span class="hljs-string">'c##'</span>: { <span class="hljs-attr">root_index</span>: <span class="hljs-number">0</span>, <span class="hljs-attr">int_val</span>: <span class="hljs-number">2</span> }, <span class="hljs-string">'cb'</span>: { <span class="hljs-attr">root_index</span>: <span class="hljs-number">0</span>, <span class="hljs-attr">int_val</span>: <span class="hljs-number">11</span> }, <span class="hljs-string">'cbb'</span>: { <span class="hljs-attr">root_index</span>: <span class="hljs-number">0</span>, <span class="hljs-attr">int_val</span>: <span class="hljs-number">10</span> }, <span class="hljs-string">'d'</span>: { <span class="hljs-attr">root_index</span>: <span class="hljs-number">1</span>, <span class="hljs-attr">int_val</span>: <span class="hljs-number">2</span> }, <span class="hljs-string">'dn'</span>: { <span class="hljs-attr">root_index</span>: <span class="hljs-number">1</span>, <span class="hljs-attr">int_val</span>: <span class="hljs-number">2</span> }, <span class="hljs-string">'d#'</span>: { <span class="hljs-attr">root_index</span>: <span class="hljs-number">1</span>, <span class="hljs-attr">int_val</span>: <span class="hljs-number">3</span> }, <span class="hljs-string">'d##'</span>: { <span class="hljs-attr">root_index</span>: <span class="hljs-number">1</span>, <span class="hljs-attr">int_val</span>: <span class="hljs-number">4</span> }, <span class="hljs-string">'db'</span>: { <span class="hljs-attr">root_index</span>: <span class="hljs-number">1</span>, <span class="hljs-attr">int_val</span>: <span class="hljs-number">1</span> }, <span class="hljs-string">'dbb'</span>: { <span class="hljs-attr">root_index</span>: <span class="hljs-number">1</span>, <span class="hljs-attr">int_val</span>: <span class="hljs-number">0</span> }, <span class="hljs-string">'e'</span>: { <span class="hljs-attr">root_index</span>: <span class="hljs-number">2</span>, <span class="hljs-attr">int_val</span>: <span class="hljs-number">4</span> }, <span class="hljs-string">'en'</span>: { <span class="hljs-attr">root_index</span>: <span class="hljs-number">2</span>, <span class="hljs-attr">int_val</span>: <span class="hljs-number">4</span> }, <span class="hljs-string">'e#'</span>: { <span class="hljs-attr">root_index</span>: <span class="hljs-number">2</span>, <span class="hljs-attr">int_val</span>: <span class="hljs-number">5</span> }, <span class="hljs-string">'e##'</span>: { <span class="hljs-attr">root_index</span>: <span class="hljs-number">2</span>, <span class="hljs-attr">int_val</span>: <span class="hljs-number">6</span> }, <span class="hljs-string">'eb'</span>: { <span class="hljs-attr">root_index</span>: <span class="hljs-number">2</span>, <span class="hljs-attr">int_val</span>: <span class="hljs-number">3</span> }, <span class="hljs-string">'ebb'</span>: { <span class="hljs-attr">root_index</span>: <span class="hljs-number">2</span>, <span class="hljs-attr">int_val</span>: <span class="hljs-number">2</span> }, <span class="hljs-string">'f'</span>: { <span class="hljs-attr">root_index</span>: <span class="hljs-number">3</span>, <span class="hljs-attr">int_val</span>: <span class="hljs-number">5</span> }, <span class="hljs-string">'fn'</span>: { <span class="hljs-attr">root_index</span>: <span class="hljs-number">3</span>, <span class="hljs-attr">int_val</span>: <span class="hljs-number">5</span> }, <span class="hljs-string">'f#'</span>: { <span class="hljs-attr">root_index</span>: <span class="hljs-number">3</span>, <span class="hljs-attr">int_val</span>: <span class="hljs-number">6</span> }, <span class="hljs-string">'f##'</span>: { <span class="hljs-attr">root_index</span>: <span class="hljs-number">3</span>, <span class="hljs-attr">int_val</span>: <span class="hljs-number">7</span> }, <span class="hljs-string">'fb'</span>: { <span class="hljs-attr">root_index</span>: <span class="hljs-number">3</span>, <span class="hljs-attr">int_val</span>: <span class="hljs-number">4</span> }, <span class="hljs-string">'fbb'</span>: { <span class="hljs-attr">root_index</span>: <span class="hljs-number">3</span>, <span class="hljs-attr">int_val</span>: <span class="hljs-number">3</span> }, <span class="hljs-string">'g'</span>: { <span class="hljs-attr">root_index</span>: <span class="hljs-number">4</span>, <span class="hljs-attr">int_val</span>: <span class="hljs-number">7</span> }, <span class="hljs-string">'gn'</span>: { <span class="hljs-attr">root_index</span>: <span class="hljs-number">4</span>, <span class="hljs-attr">int_val</span>: <span class="hljs-number">7</span> }, <span class="hljs-string">'g#'</span>: { <span class="hljs-attr">root_index</span>: <span class="hljs-number">4</span>, <span class="hljs-attr">int_val</span>: <span class="hljs-number">8</span> }, <span class="hljs-string">'g##'</span>: { <span class="hljs-attr">root_index</span>: <span class="hljs-number">4</span>, <span class="hljs-attr">int_val</span>: <span class="hljs-number">9</span> }, <span class="hljs-string">'gb'</span>: { <span class="hljs-attr">root_index</span>: <span class="hljs-number">4</span>, <span class="hljs-attr">int_val</span>: <span class="hljs-number">6</span> }, <span class="hljs-string">'gbb'</span>: { <span class="hljs-attr">root_index</span>: <span class="hljs-number">4</span>, <span class="hljs-attr">int_val</span>: <span class="hljs-number">5</span> }, <span class="hljs-string">'a'</span>: { <span class="hljs-attr">root_index</span>: <span class="hljs-number">5</span>, <span class="hljs-attr">int_val</span>: <span class="hljs-number">9</span> }, <span class="hljs-string">'an'</span>: { <span class="hljs-attr">root_index</span>: <span class="hljs-number">5</span>, <span class="hljs-attr">int_val</span>: <span class="hljs-number">9</span> }, <span class="hljs-string">'a#'</span>: { <span class="hljs-attr">root_index</span>: <span class="hljs-number">5</span>, <span class="hljs-attr">int_val</span>: <span class="hljs-number">10</span> }, <span class="hljs-string">'a##'</span>: { <span class="hljs-attr">root_index</span>: <span class="hljs-number">5</span>, <span class="hljs-attr">int_val</span>: <span class="hljs-number">11</span> }, <span class="hljs-string">'ab'</span>: { <span class="hljs-attr">root_index</span>: <span class="hljs-number">5</span>, <span class="hljs-attr">int_val</span>: <span class="hljs-number">8</span> }, <span class="hljs-string">'abb'</span>: { <span class="hljs-attr">root_index</span>: <span class="hljs-number">5</span>, <span class="hljs-attr">int_val</span>: <span class="hljs-number">7</span> }, <span class="hljs-string">'b'</span>: { <span class="hljs-attr">root_index</span>: <span class="hljs-number">6</span>, <span class="hljs-attr">int_val</span>: <span class="hljs-number">11</span> }, <span class="hljs-string">'bn'</span>: { <span class="hljs-attr">root_index</span>: <span class="hljs-number">6</span>, <span class="hljs-attr">int_val</span>: <span class="hljs-number">11</span> }, <span class="hljs-string">'b#'</span>: { <span class="hljs-attr">root_index</span>: <span class="hljs-number">6</span>, <span class="hljs-attr">int_val</span>: <span class="hljs-number">0</span> }, <span class="hljs-string">'b##'</span>: { <span class="hljs-attr">root_index</span>: <span class="hljs-number">6</span>, <span class="hljs-attr">int_val</span>: <span class="hljs-number">1</span> }, <span class="hljs-string">'bb'</span>: { <span class="hljs-attr">root_index</span>: <span class="hljs-number">6</span>, <span class="hljs-attr">int_val</span>: <span class="hljs-number">10</span> }, <span class="hljs-string">'bbb'</span>: { <span class="hljs-attr">root_index</span>: <span class="hljs-number">6</span>, <span class="hljs-attr">int_val</span>: <span class="hljs-number">9</span> }, }; } isValidNoteValue(note) { <span class="hljs-keyword">if</span> (note == <span class="hljs-literal">null</span> || note &lt; <span class="hljs-number">0</span> || note &gt;= Music.NUM_TONES) { <span class="hljs-keyword">return</span> <span class="hljs-literal">false</span>; } <span class="hljs-keyword">return</span> <span class="hljs-literal">true</span>; } isValidIntervalValue(interval) { <span class="hljs-keyword">return</span> <span class="hljs-keyword">this</span>.isValidNoteValue(interval); } getNoteParts(noteString) { <span class="hljs-keyword">if</span> (!noteString || noteString.length &lt; <span class="hljs-number">1</span>) { <span class="hljs-keyword">throw</span> <span class="hljs-keyword">new</span> Vex.RERR(<span class="hljs-string">'BadArguments'</span>, <span class="hljs-string">'Invalid note name: '</span> + noteString); } <span class="hljs-keyword">if</span> (noteString.length &gt; <span class="hljs-number">3</span>) { <span class="hljs-keyword">throw</span> <span class="hljs-keyword">new</span> Vex.RERR(<span class="hljs-string">'BadArguments'</span>, <span class="hljs-string">'Invalid note name: '</span> + noteString); } <span class="hljs-keyword">const</span> note = noteString.toLowerCase(); <span class="hljs-keyword">const</span> regex = <span class="hljs-regexp">/^([cdefgab])(b|bb|n|#|##)?$/</span>; <span class="hljs-keyword">const</span> match = regex.exec(note); <span class="hljs-keyword">if</span> (match != <span class="hljs-literal">null</span>) { <span class="hljs-keyword">const</span> root = match[<span class="hljs-number">1</span>]; <span class="hljs-keyword">const</span> accidental = match[<span class="hljs-number">2</span>]; <span class="hljs-keyword">return</span> { root, accidental, }; } <span class="hljs-keyword">else</span> { <span class="hljs-keyword">throw</span> <span class="hljs-keyword">new</span> Vex.RERR(<span class="hljs-string">'BadArguments'</span>, <span class="hljs-string">'Invalid note name: '</span> + noteString); } } getKeyParts(keyString) { <span class="hljs-keyword">if</span> (!keyString || keyString.length &lt; <span class="hljs-number">1</span>) { <span class="hljs-keyword">throw</span> <span class="hljs-keyword">new</span> Vex.RERR(<span class="hljs-string">'BadArguments'</span>, <span class="hljs-string">'Invalid key: '</span> + keyString); } <span class="hljs-keyword">const</span> key = keyString.toLowerCase();</pre></div> <p>Support Major, Minor, Melodic Minor, and Harmonic Minor key types.</p> <div class='highlight'><pre> <span class="hljs-keyword">const</span> regex = <span class="hljs-regexp">/^([cdefgab])(b|#)?(mel|harm|m|M)?$/</span>; <span class="hljs-keyword">const</span> match = regex.exec(key); <span class="hljs-keyword">if</span> (match != <span class="hljs-literal">null</span>) { <span class="hljs-keyword">const</span> root = match[<span class="hljs-number">1</span>]; <span class="hljs-keyword">const</span> accidental = match[<span class="hljs-number">2</span>]; <span class="hljs-keyword">let</span> type = match[<span class="hljs-number">3</span>];</pre></div> <p>Unspecified type implies major</p> <div class='highlight'><pre> <span class="hljs-keyword">if</span> (!type) type = <span class="hljs-string">'M'</span>; <span class="hljs-keyword">return</span> { root, accidental, type, }; } <span class="hljs-keyword">else</span> { <span class="hljs-keyword">throw</span> <span class="hljs-keyword">new</span> Vex.RERR(<span class="hljs-string">'BadArguments'</span>, <span class="hljs-string">`Invalid key: <span class="hljs-subst">${keyString}</span>`</span>); } } getNoteValue(noteString) { <span class="hljs-keyword">const</span> value = Music.noteValues[noteString]; <span class="hljs-keyword">if</span> (value == <span class="hljs-literal">null</span>) { <span class="hljs-keyword">throw</span> <span class="hljs-keyword">new</span> Vex.RERR(<span class="hljs-string">'BadArguments'</span>, <span class="hljs-string">`Invalid note name: <span class="hljs-subst">${noteString}</span>`</span>); } <span class="hljs-keyword">return</span> value.int_val; } getIntervalValue(intervalString) { <span class="hljs-keyword">const</span> value = Music.intervals[intervalString]; <span class="hljs-keyword">if</span> (value == <span class="hljs-literal">null</span>) { <span class="hljs-keyword">throw</span> <span class="hljs-keyword">new</span> Vex.RERR(<span class="hljs-string">'BadArguments'</span>, <span class="hljs-string">`Invalid interval name: <span class="hljs-subst">${intervalString}</span>`</span>); } <span class="hljs-keyword">return</span> value; } getCanonicalNoteName(noteValue) { <span class="hljs-keyword">if</span> (!<span class="hljs-keyword">this</span>.isValidNoteValue(noteValue)) { <span class="hljs-keyword">throw</span> <span class="hljs-keyword">new</span> Vex.RERR(<span class="hljs-string">'BadArguments'</span>, <span class="hljs-string">`Invalid note value: <span class="hljs-subst">${noteValue}</span>`</span>); } <span class="hljs-keyword">return</span> Music.canonical_notes[noteValue]; } getCanonicalIntervalName(intervalValue) { <span class="hljs-keyword">if</span> (!<span class="hljs-keyword">this</span>.isValidIntervalValue(intervalValue)) { <span class="hljs-keyword">throw</span> <span class="hljs-keyword">new</span> Vex.RERR(<span class="hljs-string">'BadArguments'</span>, <span class="hljs-string">`Invalid interval value: <span class="hljs-subst">${intervalValue}</span>`</span>); } <span class="hljs-keyword">return</span> Music.diatonic_intervals[intervalValue]; } <span class="hljs-comment">/* Given a note, interval, and interval direction, product the * relative note. */</span> getRelativeNoteValue(noteValue, intervalValue, direction) { <span class="hljs-keyword">if</span> (direction == <span class="hljs-literal">null</span>) direction = <span class="hljs-number">1</span>; <span class="hljs-keyword">if</span> (direction !== <span class="hljs-number">1</span> &amp;&amp; direction !== <span class="hljs-number">-1</span>) { <span class="hljs-keyword">throw</span> <span class="hljs-keyword">new</span> Vex.RERR(<span class="hljs-string">'BadArguments'</span>, <span class="hljs-string">`Invalid direction: <span class="hljs-subst">${direction}</span>`</span>); } <span class="hljs-keyword">let</span> sum = (noteValue + (direction * intervalValue)) % Music.NUM_TONES; <span class="hljs-keyword">if</span> (sum &lt; <span class="hljs-number">0</span>) sum += Music.NUM_TONES; <span class="hljs-keyword">return</span> sum; } getRelativeNoteName(root, noteValue) { <span class="hljs-keyword">const</span> parts = <span class="hljs-keyword">this</span>.getNoteParts(root); <span class="hljs-keyword">const</span> rootValue = <span class="hljs-keyword">this</span>.getNoteValue(parts.root); <span class="hljs-keyword">let</span> interval = noteValue - rootValue; <span class="hljs-keyword">if</span> (<span class="hljs-built_in">Math</span>.abs(interval) &gt; Music.NUM_TONES - <span class="hljs-number">3</span>) { <span class="hljs-keyword">let</span> multiplier = <span class="hljs-number">1</span>; <span class="hljs-keyword">if</span> (interval &gt; <span class="hljs-number">0</span>) multiplier = <span class="hljs-number">-1</span>;</pre></div> <p>Possibly wrap around. (Add +1 for modulo operator)</p> <div class='highlight'><pre> <span class="hljs-keyword">const</span> reverse_interval = (((noteValue + <span class="hljs-number">1</span>) + (rootValue + <span class="hljs-number">1</span>)) % Music.NUM_TONES) * multiplier; <span class="hljs-keyword">if</span> (<span class="hljs-built_in">Math</span>.abs(reverse_interval) &gt; <span class="hljs-number">2</span>) { <span class="hljs-keyword">throw</span> <span class="hljs-keyword">new</span> Vex.RERR(<span class="hljs-string">'BadArguments'</span>, <span class="hljs-string">`Notes not related: <span class="hljs-subst">${root}</span>, <span class="hljs-subst">${noteValue}</span>)`</span>); } <span class="hljs-keyword">else</span> { interval = reverse_interval; } } <span class="hljs-keyword">if</span> (<span class="hljs-built_in">Math</span>.abs(interval) &gt; <span class="hljs-number">2</span>) { <span class="hljs-keyword">throw</span> <span class="hljs-keyword">new</span> Vex.RERR(<span class="hljs-string">'BadArguments'</span>, <span class="hljs-string">`Notes not related: <span class="hljs-subst">${root}</span>, <span class="hljs-subst">${noteValue}</span>)`</span>); } <span class="hljs-keyword">let</span> relativeNoteName = parts.root; <span class="hljs-keyword">if</span> (interval &gt; <span class="hljs-number">0</span>) { <span class="hljs-keyword">for</span> (<span class="hljs-keyword">let</span> i = <span class="hljs-number">1</span>; i &lt;= interval; ++i) { relativeNoteName += <span class="hljs-string">'#'</span>; } } <span class="hljs-keyword">else</span> <span class="hljs-keyword">if</span> (interval &lt; <span class="hljs-number">0</span>) { <span class="hljs-keyword">for</span> (<span class="hljs-keyword">let</span> i = <span class="hljs-number">-1</span>; i &gt;= interval; --i) { relativeNoteName += <span class="hljs-string">'b'</span>; } } <span class="hljs-keyword">return</span> relativeNoteName; } <span class="hljs-comment">/* Return scale tones, given intervals. Each successive interval is * relative to the previous one, e.g., Major Scale: * * TTSTTTS = [2,2,1,2,2,2,1] * * When used with key = 0, returns C scale (which is isomorphic to * interval list). */</span> getScaleTones(key, intervals) { <span class="hljs-keyword">const</span> tones = [key]; <span class="hljs-keyword">let</span> nextNote = key; <span class="hljs-keyword">for</span> (<span class="hljs-keyword">let</span> i = <span class="hljs-number">0</span>; i &lt; intervals.length; i += <span class="hljs-number">1</span>) { nextNote = <span class="hljs-keyword">this</span>.getRelativeNoteValue(nextNote, intervals[i]); <span class="hljs-keyword">if</span> (nextNote !== key) tones.push(nextNote); } <span class="hljs-keyword">return</span> tones; } <span class="hljs-comment">/* Returns the interval of a note, given a diatonic scale. * * E.g., Given the scale C, and the note E, returns M3 */</span> getIntervalBetween(note1, note2, direction) { <span class="hljs-keyword">if</span> (direction == <span class="hljs-literal">null</span>) direction = <span class="hljs-number">1</span>; <span class="hljs-keyword">if</span> (direction !== <span class="hljs-number">1</span> &amp;&amp; direction !== <span class="hljs-number">-1</span>) { <span class="hljs-keyword">throw</span> <span class="hljs-keyword">new</span> Vex.RERR(<span class="hljs-string">'BadArguments'</span>, <span class="hljs-string">`Invalid direction: <span class="hljs-subst">${direction}</span>`</span>); } <span class="hljs-keyword">if</span> (!<span class="hljs-keyword">this</span>.isValidNoteValue(note1) || !<span class="hljs-keyword">this</span>.isValidNoteValue(note2)) { <span class="hljs-keyword">throw</span> <span class="hljs-keyword">new</span> Vex.RERR(<span class="hljs-string">'BadArguments'</span>, <span class="hljs-string">`Invalid notes: <span class="hljs-subst">${note1}</span>, <span class="hljs-subst">${note2}</span>`</span>); } <span class="hljs-keyword">let</span> difference = direction === <span class="hljs-number">1</span> ? note2 - note1 : note1 - note2; <span class="hljs-keyword">if</span> (difference &lt; <span class="hljs-number">0</span>) difference += Music.NUM_TONES; <span class="hljs-keyword">return</span> difference; }</pre></div> <p>Create a scale map that represents the pitch state for a <code>keySignature</code>. For example, passing a <code>G</code> to <code>keySignature</code> would return a scale map with every note naturalized except for <code>F</code> which has an <code>F#</code> state.</p> <div class='highlight'><pre> createScaleMap(keySignature) { <span class="hljs-keyword">const</span> keySigParts = <span class="hljs-keyword">this</span>.getKeyParts(keySignature); <span class="hljs-keyword">const</span> scaleName = Music.scaleTypes[keySigParts.type]; <span class="hljs-keyword">let</span> keySigString = keySigParts.root; <span class="hljs-keyword">if</span> (keySigParts.accidental) keySigString += keySigParts.accidental; <span class="hljs-keyword">if</span> (!scaleName) <span class="hljs-keyword">throw</span> <span class="hljs-keyword">new</span> Vex.RERR(<span class="hljs-string">'BadArguments'</span>, <span class="hljs-string">'Unsupported key type: '</span> + keySignature); <span class="hljs-keyword">const</span> scale = <span class="hljs-keyword">this</span>.g