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+<!DOCTYPE html>
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+<html lang="en">
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+ <head>
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+ <meta charset="utf-8" />
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+ <base href="../../../" />
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+ <script src="page.js"></script>
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+ <link type="text/css" rel="stylesheet" href="page.css" />
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+ </head>
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+ <body>
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+ <h1>[name]</h1>
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+
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+ <p class="desc">
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+ A class representing a 2x2
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+ [link:https://en.wikipedia.org/wiki/Matrix_(mathematics) matrix].
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+ </p>
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+
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+ <h2>Code Example</h2>
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+ <code>
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+const m = new Matrix2();
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+ </code>
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+
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+ <h2>A Note on Row-Major and Column-Major Ordering</h2>
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+ <p>
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+ The constructor and [page:set]() method take arguments in
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+ [link:https://en.wikipedia.org/wiki/Row-_and_column-major_order#Column-major_order row-major]
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+ order, while internally they are stored in the [page:.elements elements]
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+ array in column-major order.<br /><br />
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+
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+ This means that calling
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+ <code>
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+m.set( 11, 12,
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+ 21, 22 );
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+ </code>
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+ will result in the [page:.elements elements] array containing:
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+ <code>
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+m.elements = [ 11, 21,
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+ 12, 22 ];
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+ </code>
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+ and internally all calculations are performed using column-major ordering.
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+ However, as the actual ordering makes no difference mathematically and
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+ most people are used to thinking about matrices in row-major order, the
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+ three.js documentation shows matrices in row-major order. Just bear in
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+ mind that if you are reading the source code, you'll have to take the
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+ [link:https://en.wikipedia.org/wiki/Transpose transpose] of any matrices
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+ outlined here to make sense of the calculations.
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+ </p>
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+
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+ <h2>Constructor</h2>
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+
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+ <h3>[name]( [param:Number n11], [param:Number n12],
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+ [param:Number n21], [param:Number n22] )</h3>
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+ <p>
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+ Creates a 2x2 matrix with the given arguments in row-major order. If no arguments are provided, the constructor initializes
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+ the [name] to the 3x3 [link:https://en.wikipedia.org/wiki/Identity_matrix identity matrix].
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+ </p>
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+
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+ <h2>Properties</h2>
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+
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+ <h3>[property:Array elements]</h3>
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+ <p>
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+ A [link:https://en.wikipedia.org/wiki/Row-_and_column-major_order column-major] list of matrix values.
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+ </p>
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+
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+ <h2>Methods</h2>
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+
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+ <h3>
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+ [method:this fromArray]( [param:Array array], [param:Integer offset] )
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+ </h3>
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+ <p>
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+ [page:Array array] - the array to read the elements from.<br />
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+ [page:Integer offset] - (optional) index of first element in the array.
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+ Default is `0`.<br /><br />
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+
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+ Sets the elements of this matrix based on an array in
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+ [link:https://en.wikipedia.org/wiki/Row-_and_column-major_order#Column-major_order column-major] format.
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+ </p>
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+
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+ <h3>[method:this identity]()</h3>
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+ <p>
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+ Resets this matrix to the 2x2 identity matrix:
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+ </p>
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+
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+ <math display="block">
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+ <mrow>
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+ <mo>[</mo>
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+ <mtable>
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+ <mtr>
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+ <mtd><mn>1</mn></mtd>
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+ <mtd><mn>0</mn></mtd>
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+ </mtr>
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+ <mtr>
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+ <mtd><mn>0</mn></mtd>
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+ <mtd><mn>1</mn></mtd>
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+ </mtr>
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+ </mtable>
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+ <mo>]</mo>
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+ </mrow>
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+ </math>
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+
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+ <h3>
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+ [method:this set]( [param:Float n11], [param:Float n12], [param:Float n21], [param:Float n22] )
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+ </h3>
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+ <p>
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+ Sets the 2x2 matrix values to the given
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+ [link:https://en.wikipedia.org/wiki/Row-_and_column-major_order row-major]
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+ sequence of values:
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+ </p>
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+
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+ <math display="block">
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+ <mrow>
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+ <mo>[</mo>
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+ <mtable>
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+ <mtr>
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+ <mtd><mi>n11</mi></mtd>
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+ <mtd><mi>n12</mi></mtd>
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+ </mtr>
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+ <mtr>
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+ <mtd><mi>n21</mi></mtd>
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+ <mtd><mi>n22</mi></mtd>
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+ </mtr>
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+ </mtable>
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+ <mo>]</mo>
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+ </mrow>
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+ </math>
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+
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+ <h2>Source</h2>
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+
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+ <p>
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+ [link:https://github.com/mrdoob/three.js/blob/master/src/[path].js src/[path].js]
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+ </p>
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+ </body>
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+</html>
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Garrett Johnson