VexFlow 演奏順序記号

VexFlow 使い方に戻る。

概要

　演奏順序記号の描き方について説明します。

コード	表示内容
Barline.type.SINGLE	一本線
Barline.type.DOUBLE	二本線
Barline.type.END	二本線で右側が太線
Barline.type.REPEAT_BEGIN	リピート開始記号
Barline.type.REPEAT_END	リピート終了記号
Barline.type.REPEAT_BOTH	リピート両側記号
Barline.type.NONE	線無し

　

演奏順序記号

　コードは以下のとおりです。

<div id="yonet202403Mid_Output01"></div>
<script>
var VF = Vex.Flow;
(function(){
const {
  Factory,
  Stave,
  StaveNote,
  Formatter,
  Voice,
  StaveTie,
  BarLine,
  Repetition,
  Volta,
  Renderer
} = Vex.Flow;

let nscale = 0.68
let nwidth = 1040;
let nheight = 420;

let nHeadMargin = 70;
let nStaveWidth = 350;

const f = new Factory({ 
  renderer: { elementId: 'yonet202403Mid_Output01', width: nwidth, height: nheight * nscale }
  });
const ctx = f.getContext();
ctx.scale(nscale, nscale);

const defaultStyle = {
  lineWidth: ctx.lineWidth,
  strokeStyle: ctx.strokeStyle,
};

for (let i = 0; i <= nwidth * (1 / nscale); i += 10) {
  ctx.beginPath();
  ctx.moveTo(0 + i, 0);
  ctx.lineTo(0 + i, nheight);
  if (i % 100 === 0){
    ctx.setLineWidth(1);
    ctx.setStrokeStyle('rgba(200, 200, 200, 0.8)');
  }
  else{
    ctx.setLineWidth(0.5);
    ctx.setStrokeStyle('rgba(230, 230, 230, 0.8)');
  }
  ctx.stroke();
}

for (let i = 0; i <= nheight; i += 10) {
  ctx.beginPath();
  ctx.moveTo(0, i);
  ctx.lineTo(nwidth * (1 / nscale), i);
  if (i % 100 === 0){
    ctx.setLineWidth(1);
    ctx.setStrokeStyle('rgba(200, 200, 200, 0.8)');
  }
  else{
    ctx.setLineWidth(0.5);
    ctx.setStrokeStyle('rgba(230, 230, 230, 0.8)');
  }
  ctx.stroke();
}

ctx.lineWidth = defaultStyle.lineWidth;
ctx.strokeStyle = defaultStyle.strokeStyle;

const stave1 = new Stave(10, 50, nHeadMargin + nStaveWidth).setContext(ctx);
stave1.setClef("treble").setContext(ctx);
stave1.setTimeSignature('4/4').setContext(ctx);
//stave1.setBegBarType(4);//BarLine.type.REPEAT_BEGIN
stave1.setBegBarType(VF.Barline.type.REPEAT_BEGIN);//BarLine.type.REPEAT_BEGIN
stave1.draw();

//SINGLE:1, DOUBLE:2, END:3, REPEAT_BEGIN:4, REPEAT_END:5, REPEAT_BOTH:6, NONE:7

const notes1 = [
  new StaveNote({ keys: ["d/5"], duration: "q" }),
  new StaveNote({ keys: ["e/5"], duration: "q" }),
  new StaveNote({ keys: ["f/5"], duration: "q" }),
  new StaveNote({ keys: ["g/5"], duration: "q" }),
];

Formatter.FormatAndDraw(ctx, stave1, notes1);

const tie1 = new StaveTie({
  first_note: notes1[1],
  last_note: notes1[2],
  first_indices: [0],
  last_indices: [0],
});

const tie2 = new StaveTie({
  first_note: notes1[2],
  last_note: notes1[3],
  first_indices: [0],
  last_indices: [0],
});

tie1.setContext(ctx).draw();
tie2.setContext(ctx).draw();


const stave2 = new Stave(stave1.width + stave1.x, stave1.y, nStaveWidth).setContext(ctx);
stave2.setEndBarType(VF.Barline.type.REPEAT_END);
stave2.setVoltaType(VF.Volta.type.BEGIN, "1.", 10);
stave2.draw();


const stave3 = new Stave(stave2.width + stave2.x, stave1.y, nStaveWidth/2).setContext(ctx);
stave3.setVoltaType(VF.Volta.type.BEGIN, "2.", 10);
stave3.draw();


const stave4 = new Stave(stave3.width + stave3.x, stave1.y, nStaveWidth/2).setContext(ctx);
stave4.setVoltaType(VF.Volta.type.MID, "", 10);
stave4.draw();


const stave5 = new Stave(stave4.width + stave4.x, stave1.y, nStaveWidth/2).setContext(ctx);
stave5.setVoltaType(VF.Volta.type.MID, "", 10);
stave5.draw();


const stave6 = new Stave(stave5.width + stave5.x, stave1.y, nStaveWidth/2).setContext(ctx);
stave6.setVoltaType(VF.Volta.type.END, "", 10);
stave6.setEndBarType(VF.Barline.type.REPEAT_END);
stave6.draw();


const stave7 = new Stave(stave1.x, stave1.y + 200, nHeadMargin + nStaveWidth).setContext(ctx);
stave7.addClef("treble").setContext(ctx);
stave7.addTimeSignature('4/4').setContext(ctx);
stave7.setVoltaType(VF.Volta.type.BEGIN_END, "3.", 10);
stave7.setEndBarType(VF.Barline.type.SINGLE);//規定値(省略可能)

stave7.draw();

const notes7 = [
  new StaveNote({ keys: ["a/4"], duration: "q" }),
  new StaveNote({ keys: ["b/4"], duration: "q" }),
  new StaveNote({ keys: ["c/5"], duration: "q" }),
  new StaveNote({ keys: ["d/5"], duration: "q" }),
];

Formatter.FormatAndDraw(ctx, stave7, notes7);

const tie3 = new StaveTie({
  first_note: notes7[1],
  last_note: notes7[2],
  first_indices: [0],
  last_indices: [0],
});

const tie4 = new StaveTie({
  first_note: notes7[2],
  last_note: notes7[3],
  first_indices: [0],
  last_indices: [0],
});

tie3.setContext(ctx).draw();
tie4.setContext(ctx).draw();

const stave8 = new Stave(stave7.width + stave7.x, stave7.y, nStaveWidth).setContext(ctx);
stave8.setEndBarType(VF.Barline.type.DOUBLE);

stave8.draw();

const notes8 = [
  new StaveNote({ keys: ["e/5"], duration: "q" }),
  new StaveNote({ keys: ["f/5"], duration: "q" }),
  new StaveNote({ keys: ["g/5"], duration: "q" }),
  new StaveNote({ keys: ["a/5"], duration: "q" }),
];

Formatter.FormatAndDraw(ctx, stave8, notes8);

const tie5 = new StaveTie({
  first_note: notes7[3],
  last_note: notes8[0],
  first_indices: [0],
  last_indices: [0],
});

tie5.setContext(ctx).draw();


const stave9 = new Stave(stave8.width + stave8.x, stave7.y, nStaveWidth).setContext(ctx);
stave9.setRepetitionType(VF.Repetition.type.SEGNO_LEFT, 30);
stave9.setRepetitionType(VF.Repetition.type.CODA_RIGHT, 10);
stave9.draw();


const stave10 = new Stave(stave9.width + stave9.x, stave7.y, nStaveWidth).setContext(ctx);
stave10.setEndBarType(VF.Barline.type.END);
stave10.draw();

ctx.setFillStyle('#F5F5F5');
ctx.fillRect(0, 0, f.width, f.height);

})();

const svgElement = document.querySelector('#Output svg');
svgElement.style.backgroundColor = '#F5F5F5';
</script>

　VFというオブジェクトをvar VF = Vex.Flowと定義しておくと、Barlineのようなオブジェクト定数を保持しているものにアクセスできるようになります。VF.Barlineのように使います。VexFlow公式のExamplesでもそのように設定されていました。いきなりBarline.type.ENDのように使おうとしても未定義になるようです。冷たいな。

　あと、規定値でStaveつまり小節をつくると線が引かれるので、線をなくすときは、終了位置からも開始位置からもNONEを設定しないとどちらかが規定値で描画されたときに線がひかれてしまいますので、気を付けたいですね。SINGLEが規定値です。

　

VexFlow 使い方に戻る。