VexFlow 小節開始終了線のソースを表示

<yjavascript></script>
<script src="https://wiki.yo-net.jp/vexflow/build/cjs/vexflow.js"></script>
<script>
</yjavascript>
[[VexFlow 使い方]]に戻る。
== '''概要''' ==
　小節区切りの設定をする手順を示します。約1年近く絶賛挫折中でしたが、久しぶりに更新しました。2024年3月中旬時点。このサイトのこの記事がかなり世の中的に期待されているようです。続編を書かないといけないなと思った次第です。次の記事も頑張っていこう！


<table style="border: 0; border-collapse: collapse;">
<tr border="0" style="color: white; background-color:#666666; font-weight: bolder;">
  <td>コード</td>
  <td>表示内容</td>
</tr>
<tr>
  <td>Barline.type.SINGLE</td>
  <td>一本線</td>
</tr>
<tr style="background-color: #cccccc;">
  <td>Barline.type.DOUBLE</td>
  <td>二本線</td>
</tr>
<tr>
  <td>Barline.type.END</td>
  <td>二本線で右側が太線</td>
</tr>
<tr style="background-color: #cccccc;">
  <td>Barline.type.REPEAT_BEGIN</td>
  <td>リピート開始記号</td>
</tr>
<tr>
  <td>Barline.type.REPEAT_END</td>
  <td>リピート終了記号</td>
</tr>
<tr style="background-color: #cccccc;">
  <td>Barline.type.REPEAT_BOTH</td>
  <td>リピート両側記号</td>
</tr>
<tr>
  <td>Barline.type.NONE</td>
  <td>線無し</td>
</tr>
</table>

　

== '''小節開始終了線''' ==
<div id="yonet202403Mid_Output01"></div>
<yjavascript></script>
<script>
var VF = Vex.Flow;
(function(){
const {
  Factory,
  Stave,
  StaveNote,
  Formatter,
  Voice,
  StaveTie,
  BarLine,
  Renderer
} = Vex.Flow;

let nscale = 0.68
let nwidth = 1040;
let nheight = 320;

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_BOTH);
stave2.draw();


const stave3 = new Stave(stave2.width + stave2.x, stave1.y, nStaveWidth).setContext(ctx);
stave3.setEndBarType(VF.Barline.type.NONE);
stave3.draw();


const stave4 = new Stave(stave3.width + stave3.x, stave1.y, nStaveWidth).setContext(ctx);
stave4.setBegBarType(VF.Barline.type.NONE);
stave4.setEndBarType(VF.Barline.type.REPEAT_END);
stave4.draw();


const stave5 = new Stave(stave1.x, stave1.y + 100, nHeadMargin + nStaveWidth).setContext(ctx);
stave5.addClef("treble").setContext(ctx);
stave5.addTimeSignature('4/4').setContext(ctx);
stave5.setEndBarType(VF.Barline.type.SINGLE);//規定値(省略可能)

stave5.draw();

const notes5 = [
  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, stave5, notes5);

const tie3 = new StaveTie({
  first_note: notes5[1],
  last_note: notes5[2],
  first_indices: [0],
  last_indices: [0],
});

const tie4 = new StaveTie({
  first_note: notes5[2],
  last_note: notes5[3],
  first_indices: [0],
  last_indices: [0],
});

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

const stave6 = new Stave(stave5.width + stave5.x, stave5.y, nStaveWidth).setContext(ctx);
stave6.setEndBarType(VF.Barline.type.DOUBLE);

stave6.draw();

const notes6 = [
  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, stave6, notes6);

const tie5 = new StaveTie({
  first_note: notes5[3],
  last_note: notes6[0],
  first_indices: [0],
  last_indices: [0],
});

tie5.setContext(ctx).draw();


const stave7 = new Stave(stave6.width + stave6.x, stave5.y, nStaveWidth).setContext(ctx);
stave7.draw();


const stave8 = new Stave(stave7.width + stave7.x, stave5.y, nStaveWidth).setContext(ctx);
stave8.setEndBarType(VF.Barline.type.END);
stave8.draw();

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

})();

const svgElement = document.querySelector('#Output svg');
svgElement.style.backgroundColor = '#F5F5F5';
const svgNS = 'http://www.w3.org/2000/svg';
const lineColor = '#EEEEEE';
</yjavascript>

　コードは以下のとおりです。

<syntaxhighlight lang="javascript" line start="1">
<div id="yonet202403Mid_Output01"></div>
<script>
var VF = Vex.Flow;
(function(){
const {
  Factory,
  Stave,
  StaveNote,
  Formatter,
  Voice,
  StaveTie,
  BarLine,
  Renderer
} = Vex.Flow;

let nscale = 0.68
let nwidth = 1040;
let nheight = 320;

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_BOTH);
stave2.draw();


const stave3 = new Stave(stave2.width + stave2.x, stave1.y, nStaveWidth).setContext(ctx);
stave3.setEndBarType(VF.Barline.type.NONE);
stave3.draw();


const stave4 = new Stave(stave3.width + stave3.x, stave1.y, nStaveWidth).setContext(ctx);
stave4.setBegBarType(VF.Barline.type.NONE);
stave4.setEndBarType(VF.Barline.type.REPEAT_END);
stave4.draw();


const stave5 = new Stave(stave1.x, stave1.y + 100, nHeadMargin + nStaveWidth).setContext(ctx);
stave5.addClef("treble").setContext(ctx);
stave5.addTimeSignature('4/4').setContext(ctx);
stave5.setEndBarType(VF.Barline.type.SINGLE);//規定値(省略可能)

stave5.draw();

const notes5 = [
  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, stave5, notes5);

const tie3 = new StaveTie({
  first_note: notes5[1],
  last_note: notes5[2],
  first_indices: [0],
  last_indices: [0],
});

const tie4 = new StaveTie({
  first_note: notes5[2],
  last_note: notes5[3],
  first_indices: [0],
  last_indices: [0],
});

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

const stave6 = new Stave(stave5.width + stave5.x, stave5.y, nStaveWidth).setContext(ctx);
stave6.setEndBarType(VF.Barline.type.DOUBLE);

stave6.draw();

const notes6 = [
  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, stave6, notes6);

const tie5 = new StaveTie({
  first_note: notes5[3],
  last_note: notes6[0],
  first_indices: [0],
  last_indices: [0],
});

tie5.setContext(ctx).draw();


const stave7 = new Stave(stave6.width + stave6.x, stave5.y, nStaveWidth).setContext(ctx);
stave7.draw();


const stave8 = new Stave(stave7.width + stave7.x, stave5.y, nStaveWidth).setContext(ctx);
stave8.setEndBarType(VF.Barline.type.END);
stave8.draw();

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

})();

const svgElement = document.querySelector('#Output svg');
svgElement.style.backgroundColor = '#F5F5F5';
const svgNS = 'http://www.w3.org/2000/svg';
const lineColor = '#EEEEEE';
</script>
</syntaxhighlight>


　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。