vexflow
Version:
A JavaScript library for rendering music notation and guitar tablature
790 lines (532 loc) • 24.3 kB
HTML
<html>
<head>
<title>crescendo.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>crescendo.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 file implements the <code>Crescendo</code> object which draws crescendos and
decrescendo dynamics markings. A <code>Crescendo</code> is initialized with a
duration and formatted as part of a <code>Voice</code> like any other <code>Note</code>
type in VexFlow. This object would most likely be formatted in a Voice
with <code>TextNotes</code> - which are used to represent other dynamics markings.</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">import</span> { Note } <span class="hljs-keyword">from</span> <span class="hljs-string">'./note'</span>;
<span class="hljs-keyword">import</span> { TickContext } <span class="hljs-keyword">from</span> <span class="hljs-string">'./tickcontext'</span>;</pre></div>
<p>To enable logging for this class. Set <code>Vex.Flow.Crescendo.DEBUG</code> to <code>true</code>.</p>
<div class='highlight'><pre><span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">L</span>(<span class="hljs-params">...args</span>) </span>{ <span class="hljs-keyword">if</span> (Crescendo.DEBUG) Vex.L(<span class="hljs-string">'Vex.Flow.Crescendo'</span>, args); }</pre></div>
<p>Private helper to draw the hairpin</p>
<div class='highlight'><pre><span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">renderHairpin</span>(<span class="hljs-params">ctx, params</span>) </span>{
<span class="hljs-keyword">const</span> begin_x = params.begin_x;
<span class="hljs-keyword">const</span> end_x = params.end_x;
<span class="hljs-keyword">const</span> y = params.y;
<span class="hljs-keyword">const</span> half_height = params.height / <span class="hljs-number">2</span>;
ctx.beginPath();
<span class="hljs-keyword">if</span> (params.reverse) {
ctx.moveTo(begin_x, y - half_height);
ctx.lineTo(end_x, y);
ctx.lineTo(begin_x, y + half_height);
} <span class="hljs-keyword">else</span> {
ctx.moveTo(end_x, y - half_height);
ctx.lineTo(begin_x, y);
ctx.lineTo(end_x, y + half_height);
}
ctx.stroke();
ctx.closePath();
}
<span class="hljs-keyword">export</span> <span class="hljs-class"><span class="hljs-keyword">class</span> <span class="hljs-title">Crescendo</span> <span class="hljs-keyword">extends</span> <span class="hljs-title">Note</span> </span>{</pre></div>
<p>Initialize the crescendo’s properties</p>
<div class='highlight'><pre> <span class="hljs-keyword">constructor</span>(note_struct) {
<span class="hljs-keyword">super</span>(note_struct);
<span class="hljs-keyword">this</span>.setAttribute(<span class="hljs-string">'type'</span>, <span class="hljs-string">'Crescendo'</span>);</pre></div>
<p>Whether the object is a decrescendo</p>
<div class='highlight'><pre> <span class="hljs-keyword">this</span>.decrescendo = <span class="hljs-literal">false</span>;</pre></div>
<p>The staff line to be placed on</p>
<div class='highlight'><pre> <span class="hljs-keyword">this</span>.line = note_struct.line || <span class="hljs-number">0</span>;</pre></div>
<p>The height at the open end of the cresc/decresc</p>
<div class='highlight'><pre> <span class="hljs-keyword">this</span>.height = <span class="hljs-number">15</span>;
Vex.Merge(<span class="hljs-keyword">this</span>.render_options, {</pre></div>
<p>Extensions to the length of the crescendo on either side</p>
<div class='highlight'><pre> extend_left: <span class="hljs-number">0</span>,
<span class="hljs-attr">extend_right</span>: <span class="hljs-number">0</span>,</pre></div>
<p>Vertical shift</p>
<div class='highlight'><pre> y_shift: <span class="hljs-number">0</span>,
});
}</pre></div>
<p>Set the line to center the element on</p>
<div class='highlight'><pre> setLine(line) { <span class="hljs-keyword">this</span>.line = line; <span class="hljs-keyword">return</span> <span class="hljs-keyword">this</span>; }</pre></div>
<p>Set the full height at the open end</p>
<div class='highlight'><pre> setHeight(height) { <span class="hljs-keyword">this</span>.height = height; <span class="hljs-keyword">return</span> <span class="hljs-keyword">this</span>; }</pre></div>
<p>Set whether the sign should be a descresendo by passing a bool
to <code>decresc</code></p>
<div class='highlight'><pre> setDecrescendo(decresc) {
<span class="hljs-keyword">this</span>.decrescendo = decresc;
<span class="hljs-keyword">return</span> <span class="hljs-keyword">this</span>;
}</pre></div>
<p>Preformat the note</p>
<div class='highlight'><pre> preFormat() { <span class="hljs-keyword">this</span>.preFormatted = <span class="hljs-literal">true</span>; <span class="hljs-keyword">return</span> <span class="hljs-keyword">this</span>; }</pre></div>
<p>Render the Crescendo object onto the canvas</p>
<div class='highlight'><pre> draw() {
<span class="hljs-keyword">this</span>.checkContext();
<span class="hljs-keyword">this</span>.setRendered();
<span class="hljs-keyword">const</span> tick_context = <span class="hljs-keyword">this</span>.getTickContext();
<span class="hljs-keyword">const</span> next_context = TickContext.getNextContext(tick_context);
<span class="hljs-keyword">const</span> begin_x = <span class="hljs-keyword">this</span>.getAbsoluteX();
<span class="hljs-keyword">const</span> end_x = next_context ? next_context.getX() : <span class="hljs-keyword">this</span>.stave.x + <span class="hljs-keyword">this</span>.stave.width;
<span class="hljs-keyword">const</span> y = <span class="hljs-keyword">this</span>.stave.getYForLine(<span class="hljs-keyword">this</span>.line + (<span class="hljs-number">-3</span>)) + <span class="hljs-number">1</span>;
L(
<span class="hljs-string">'Drawing '</span>,
<span class="hljs-keyword">this</span>.decrescendo ? <span class="hljs-string">'decrescendo '</span> : <span class="hljs-string">'crescendo '</span>,
<span class="hljs-keyword">this</span>.height,
<span class="hljs-string">'x'</span>,
begin_x - end_x
);
renderHairpin(<span class="hljs-keyword">this</span>.context, {
<span class="hljs-attr">begin_x</span>: begin_x - <span class="hljs-keyword">this</span>.render_options.extend_left,
<span class="hljs-attr">end_x</span>: end_x + <span class="hljs-keyword">this</span>.render_options.extend_right,
<span class="hljs-attr">y</span>: y + <span class="hljs-keyword">this</span>.render_options.y_shift,
<span class="hljs-attr">height</span>: <span class="hljs-keyword">this</span>.height,
<span class="hljs-attr">reverse</span>: <span class="hljs-keyword">this</span>.decrescendo,
});
}
}</pre></div>
<div class="fleur">h</div>
</div>
</div>
</body>
</html>