VexFlow - Music Engraving for HTML5 Copyright Mohit Muthanna 2010
This class implements varies types of tunings for tablature.
/**
* @constructor
*/
Vex.Flow.Tuning = (function() {
function Tuning(tuningString) {
this.init(tuningString);
}
Tuning.names = {
"standard": "E/5,B/4,G/4,D/4,A/3,E/3",
"dagdad": "D/5,A/4,G/4,D/4,A/3,D/3",
"dropd": "E/5,B/4,G/4,D/4,A/3,D/3",
"eb": "Eb/5,Bb/4,Gb/4,Db/4,Ab/3,Db/3",
"standardBanjo": "D/5,B/4,G/4,D/4,G/5"
};
Tuning.prototype = {
init: function(tuningString) {Default to standard tuning.
this.setTuning(tuningString || "E/5,B/4,G/4,D/4,A/3,E/3,B/2,E/2");
},
noteToInteger: function(noteString) {
return Vex.Flow.keyProperties(noteString).int_value;
},
setTuning: function(noteString) {
if (Vex.Flow.Tuning.names[noteString])
noteString = Vex.Flow.Tuning.names[noteString];
this.tuningString = noteString;
this.tuningValues = [];
this.numStrings = 0;
var keys = noteString.split(/\s*,\s*/);
if (keys.length === 0)
throw new Vex.RERR("BadArguments", "Invalid tuning string: " + noteString);
this.numStrings = keys.length;
for (var i = 0; i < this.numStrings; ++i) {
this.tuningValues[i] = this.noteToInteger(keys[i]);
}
},
getValueForString: function(stringNum) {
var s = parseInt(stringNum, 10);
if (s < 1 || s > this.numStrings)
throw new Vex.RERR("BadArguments", "String number must be between 1 and " +
this.numStrings + ": " + stringNum);
return this.tuningValues[s - 1];
},
getValueForFret: function(fretNum, stringNum) {
var stringValue = this.getValueForString(stringNum);
var f = parseInt(fretNum, 10);
if (f < 0) {
throw new Vex.RERR("BadArguments", "Fret number must be 0 or higher: " +
fretNum);
}
return stringValue + f;
},
getNoteForFret: function(fretNum, stringNum) {
var noteValue = this.getValueForFret(fretNum, stringNum);
var octave = Math.floor(noteValue / 12);
var value = noteValue % 12;
return Vex.Flow.integerToNote(value) + "/" + octave;
}
};
return Tuning;
}());