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module-webgl-2d-math.html
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<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>WebGL Fundamentals Module: webgl-2d-math</title>
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<a class="brand" href="index.html">WebGL Fundamentals</a>
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<h1 class="page-title">Module: webgl-2d-math</h1>
<section>
<header>
<h2>
webgl-2d-math
</h2>
</header>
<article>
<div class="container-overview">
<div class="description"><p>Various 2d math functions.</p></div>
<dl class="details">
</dl>
</div>
<h3 class="subsection-title">Methods</h3>
<dl>
<dt>
<h4 class="name" id="make2DProjection"><span class="type-signature"> </span>make2DProjection<span class="signature">(width, height)</span><span class="type-signature"> → {<a href="module-webgl-2d-math.html#Matrix3">module:webgl-2d-math.Matrix3</a>}</span></h4>
</dt>
<dd>
<div class="description">
<p>Creates a 2D projection matrix</p>
</div>
<h5>Parameters:</h5>
<table class="params table table-striped">
<thead>
<tr>
<th>Name</th>
<th>Type</th>
<th class="last">Description</th>
</tr>
</thead>
<tbody>
<tr>
<td class="name"><code>width</code></td>
<td class="type">
<span class="param-type">number</span>
</td>
<td class="description last"><p>width in pixels</p></td>
</tr>
<tr>
<td class="name"><code>height</code></td>
<td class="type">
<span class="param-type">number</span>
</td>
<td class="description last"><p>height in pixels</p></td>
</tr>
</tbody>
</table>
<dl class="details">
</dl>
<h5>Returns:</h5>
<div class="param-desc">
<p>a projection matrix that converts from pixels to clipspace with Y = 0 at the top.</p>
</div>
<dl>
<dt>
Type
</dt>
<dd>
<span class="param-type"><a href="module-webgl-2d-math.html#Matrix3">module:webgl-2d-math.Matrix3</a></span>
</dd>
</dl>
</dd>
<dt>
<h4 class="name" id="makeRotation"><span class="type-signature"> </span>makeRotation<span class="signature">(angleInRadians)</span><span class="type-signature"> → {<a href="module-webgl-2d-math.html#Matrix3">module:webgl-2d-math.Matrix3</a>}</span></h4>
</dt>
<dd>
<div class="description">
<p>Creates a 2D rotation matrix</p>
</div>
<h5>Parameters:</h5>
<table class="params table table-striped">
<thead>
<tr>
<th>Name</th>
<th>Type</th>
<th class="last">Description</th>
</tr>
</thead>
<tbody>
<tr>
<td class="name"><code>angleInRadians</code></td>
<td class="type">
<span class="param-type">number</span>
</td>
<td class="description last"><p>amount to rotate in radians</p></td>
</tr>
</tbody>
</table>
<dl class="details">
</dl>
<h5>Returns:</h5>
<div class="param-desc">
<p>a rotation matrix that rotates by angleInRadians</p>
</div>
<dl>
<dt>
Type
</dt>
<dd>
<span class="param-type"><a href="module-webgl-2d-math.html#Matrix3">module:webgl-2d-math.Matrix3</a></span>
</dd>
</dl>
</dd>
<dt>
<h4 class="name" id="makeScale"><span class="type-signature"> </span>makeScale<span class="signature">(sx, sy)</span><span class="type-signature"> → {<a href="module-webgl-2d-math.html#Matrix3">module:webgl-2d-math.Matrix3</a>}</span></h4>
</dt>
<dd>
<div class="description">
<p>Creates a 2D scaling matrix</p>
</div>
<h5>Parameters:</h5>
<table class="params table table-striped">
<thead>
<tr>
<th>Name</th>
<th>Type</th>
<th class="last">Description</th>
</tr>
</thead>
<tbody>
<tr>
<td class="name"><code>sx</code></td>
<td class="type">
<span class="param-type">number</span>
</td>
<td class="description last"><p>amount to scale in x</p></td>
</tr>
<tr>
<td class="name"><code>sy</code></td>
<td class="type">
<span class="param-type">number</span>
</td>
<td class="description last"><p>amount to scale in y</p></td>
</tr>
</tbody>
</table>
<dl class="details">
</dl>
<h5>Returns:</h5>
<div class="param-desc">
<p>a scale matrix that scales by sx and sy.</p>
</div>
<dl>
<dt>
Type
</dt>
<dd>
<span class="param-type"><a href="module-webgl-2d-math.html#Matrix3">module:webgl-2d-math.Matrix3</a></span>
</dd>
</dl>
</dd>
<dt>
<h4 class="name" id="makeTranslation"><span class="type-signature"> </span>makeTranslation<span class="signature">(tx, ty)</span><span class="type-signature"> → {<a href="module-webgl-2d-math.html#Matrix3">module:webgl-2d-math.Matrix3</a>}</span></h4>
</dt>
<dd>
<div class="description">
<p>Creates a 2D translation matrix</p>
</div>
<h5>Parameters:</h5>
<table class="params table table-striped">
<thead>
<tr>
<th>Name</th>
<th>Type</th>
<th class="last">Description</th>
</tr>
</thead>
<tbody>
<tr>
<td class="name"><code>tx</code></td>
<td class="type">
<span class="param-type">number</span>
</td>
<td class="description last"><p>amount to translate in x</p></td>
</tr>
<tr>
<td class="name"><code>ty</code></td>
<td class="type">
<span class="param-type">number</span>
</td>
<td class="description last"><p>amount to translate in y</p></td>
</tr>
</tbody>
</table>
<dl class="details">
</dl>
<h5>Returns:</h5>
<div class="param-desc">
<p>a translation matrix that translates by tx and ty.</p>
</div>
<dl>
<dt>
Type
</dt>
<dd>
<span class="param-type"><a href="module-webgl-2d-math.html#Matrix3">module:webgl-2d-math.Matrix3</a></span>
</dd>
</dl>
</dd>
<dt>
<h4 class="name" id="matrixMultiply"><span class="type-signature"> </span>matrixMultiply<span class="signature">(a, b)</span><span class="type-signature"> → {<a href="module-webgl-2d-math.html#Matrix3">module:webgl-2d-math.Matrix3</a>}</span></h4>
</dt>
<dd>
<div class="description">
<p>Takes twoMatrix3s, a and b, and computes the product in the order
that pre-composes b with a. In other words, the matrix returned will</p>
</div>
<h5>Parameters:</h5>
<table class="params table table-striped">
<thead>
<tr>
<th>Name</th>
<th>Type</th>
<th class="last">Description</th>
</tr>
</thead>
<tbody>
<tr>
<td class="name"><code>a</code></td>
<td class="type">
<span class="param-type"><a href="module-webgl-2d-math.html#Matrix3">module:webgl-2d-math.Matrix3</a></span>
</td>
<td class="description last"><p>A matrix.</p></td>
</tr>
<tr>
<td class="name"><code>b</code></td>
<td class="type">
<span class="param-type"><a href="module-webgl-2d-math.html#Matrix3">module:webgl-2d-math.Matrix3</a></span>
</td>
<td class="description last"><p>A matrix.</p></td>
</tr>
</tbody>
</table>
<dl class="details">
</dl>
<h5>Returns:</h5>
<div class="param-desc">
<p>the result.</p>
</div>
<dl>
<dt>
Type
</dt>
<dd>
<span class="param-type"><a href="module-webgl-2d-math.html#Matrix3">module:webgl-2d-math.Matrix3</a></span>
</dd>
</dl>
</dd>
</dl>
<h3 class="subsection-title">Type Definitions</h3>
<dl>
<dt class="name" id="Matrix3">
<h4>Matrix3</h4>
</dt>
<dd>
<div class="description">
<p>An array or typed array with 9 values.</p>
</div>
<h5>Type:</h5>
<ul>
<li>
<span class="param-type">Array.<number>|</span>
<span class="param-type">TypedArray</span>
</li>
</ul>
<dl class="details">
</dl>
</dd>
</dl>
</article>
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