javascript
/
three.js
mirror of https://github.com/tazdij/three.js.git


			
				
					
						
						
							123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275
							<!DOCTYPE html>
<html lang="en">
	<head>
		<meta charset="utf-8" />
		<base href="../../../" />
		<script src="page.js"></script>
		<link type="text/css" rel="stylesheet" href="page.css" />
	</head>
	<body>
		<h1>[name]</h1>

		<p class="desc">
			A class representing a 3x3
			[link:https://en.wikipedia.org/wiki/Matrix_(mathematics) matrix].
		</p>

		<h2>Code Example</h2>
		<code>
const m = new Matrix3(); 
		</code>

		<h2>A Note on Row-Major and Column-Major Ordering</h2>
		<p>
			The [page:set]() method takes arguments in
			[link:https://en.wikipedia.org/wiki/Row-_and_column-major_order#Column-major_order row-major] 
			order, while internally they are stored in the [page:.elements elements] 
			array in column-major order.<br /><br />

			This means that calling
			<code>
m.set( 11, 12, 13,
       21, 22, 23,
       31, 32, 33 );
		</code>
			will result in the [page:.elements elements] array containing:
			<code> 
m.elements = [ 11, 21, 31,
			   12, 22, 32, 
			   13, 23, 33 ];
			</code>
			and internally all calculations are performed using column-major ordering.
			However, as the actual ordering makes no difference mathematically and
			most people are used to thinking about matrices in row-major order, the
			three.js documentation shows matrices in row-major order. Just bear in
			mind that if you are reading the source code, you'll have to take the
			[link:https://en.wikipedia.org/wiki/Transpose transpose] of any matrices
			outlined here to make sense of the calculations.
		</p>

		<h2>Constructor</h2>

		<h3>[name]()</h3>
		<p>
			Creates and initializes the [name] to the 3x3
			[link:https://en.wikipedia.org/wiki/Identity_matrix identity matrix].
		</p>

		<h2>Properties</h2>

		<h3>[property:Array elements]</h3>
		<p>
			A [link:https://en.wikipedia.org/wiki/Row-_and_column-major_order column-major] list of matrix values.
		</p>

		<h2>Methods</h2>

		<h3>[method:Matrix3 clone]()</h3>
		<p>Creates a new Matrix3 and with identical elements to this one.</p>

		<h3>[method:this copy]( [param:Matrix3 m] )</h3>
		<p>Copies the elements of matrix [page:Matrix3 m] into this matrix.</p>

		<h3>[method:Float determinant]()</h3>
		<p>
			Computes and returns the [link:https://en.wikipedia.org/wiki/Determinant determinant] of this matrix.
		</p>

		<h3>[method:Boolean equals]( [param:Matrix3 m] )</h3>
		<p>Return true if this matrix and [page:Matrix3 m] are equal.</p>

		<h3>
			[method:this extractBasis]( [param:Vector3 xAxis], [param:Vector3 yAxis], [param:Vector3 zAxis] )
		</h3>
		<p>
			Extracts the [link:https://en.wikipedia.org/wiki/Basis_(linear_algebra) basis] 
			of this matrix into the three axis vectors provided. If this matrix
			is:
			<code>
a, b, c, 
d, e, f, 
g, h, i 
			</code>
			then the [page:Vector3 xAxis], [page:Vector3 yAxis], [page:Vector3 zAxis]
			will be set to:
			<code>
xAxis = (a, d, g) 
yAxis = (b, e, h) 
zAxis = (c, f, i) 
			</code>
		</p>

		<h3>
			[method:this fromArray]( [param:Array array], [param:Integer offset] )
		</h3>
		<p>
			[page:Array array] - the array to read the elements from.<br />
			[page:Integer offset] - (optional) index of first element in the array.
			Default is 0.<br /><br />

			Sets the elements of this matrix based on an array in
			[link:https://en.wikipedia.org/wiki/Row-_and_column-major_order#Column-major_order column-major] format.
		</p>

		<h3>[method:this invert]()</h3>
		<p>
			Inverts this matrix, using the
			[link:https://en.wikipedia.org/wiki/Invertible_matrix#Analytic_solution analytic method]. 
			You can not invert with a determinant of zero. If you
			attempt this, the method produces a zero matrix instead.
		</p>

		<h3>[method:this getNormalMatrix]( [param:Matrix4 m] )</h3>
		<p>
			[page:Matrix4 m] - [page:Matrix4]<br /><br />

			Sets this matrix as the upper left 3x3 of the
			[link:https://en.wikipedia.org/wiki/Normal_matrix normal matrix] of the
			passed [page:Matrix4 matrix4]. 
			The normal matrix is the
			[link:https://en.wikipedia.org/wiki/Invertible_matrix inverse]
			[link:https://en.wikipedia.org/wiki/Transpose transpose] of the matrix
			[page:Matrix4 m].
		</p>

		<h3>[method:this identity]()</h3>
		<p>
			Resets this matrix to the 3x3 identity matrix:
			<code> 
1, 0, 0 
0, 1, 0 
0, 0, 1 	</code>
		</p>

		<h3>[method:this makeRotation]( [param:Float theta] )</h3>
		<p>
			[page:Float theta] — Rotation angle in radians. Positive values rotate
			counterclockwise.<br /><br />

			Sets this matrix as a 2D rotational transformation by [page:Float theta]
			radians. The resulting matrix will be:
			<code>
cos(&theta;) -sin(&theta;) 0 
sin(&theta;) cos(&theta;) 0 
0 0 1
			</code>
		</p>

		<h3>[method:this makeScale]( [param:Float x], [param:Float y] )</h3>
		<p>
			[page:Float x] - the amount to scale in the X axis.<br />
			[page:Float y] - the amount to scale in the Y axis.<br />

			Sets this matrix as a 2D scale transform:
			<code> 
x, 0, 0, 
0, y, 0, 
0, 0, 1 	</code>
		</p>

		<h3>[method:this makeTranslation]( [param:Float x], [param:Float y] )</h3>
		<p>
			[page:Float x] - the amount to translate in the X axis.<br />
			[page:Float y] - the amount to translate in the Y axis.<br />

			Sets this matrix as a 2D translation transform:
			<code>
1, 0, x, 
0, 1, y, 
0, 0, 1 	</code>
		</p>

		<h3>[method:this multiply]( [param:Matrix3 m] )</h3>
		<p>Post-multiplies this matrix by [page:Matrix3 m].</p>

		<h3>
			[method:this multiplyMatrices]( [param:Matrix3 a], [param:Matrix3 b] )
		</h3>
		<p>Sets this matrix to [page:Matrix3 a] x [page:Matrix3 b].</p>

		<h3>[method:this multiplyScalar]( [param:Float s] )</h3>
		<p>Multiplies every component of the matrix by the scalar value *s*.</p>

		<h3>[method:this rotate]( [param:Float theta] )</h3>
		<p>Rotates this matrix by the given angle (in radians).</p>

		<h3>[method:this scale]( [param:Float sx], [param:Float sy] )</h3>
		<p>Scales this matrix with the given scalar values.</p>

		<h3>
			[method:this set]( [param:Float n11], [param:Float n12], [param:Float n13], [param:Float n21], [param:Float n22], [param:Float n23], [param:Float n31], [param:Float n32], [param:Float n33] )
		</h3>
		<p>
			[page:Float n11] - value to put in row 1, col 1.<br />
			[page:Float n12] - value to put in row 1, col 2.<br />
			...<br />
			...<br />
			[page:Float n32] - value to put in row 3, col 2.<br />
			[page:Float n33] - value to put in row 3, col 3.<br /><br />

			Sets the 3x3 matrix values to the given
			[link:https://en.wikipedia.org/wiki/Row-_and_column-major_order row-major]
			sequence of values.
		</p>

		<h3>[method:this premultiply]( [param:Matrix3 m] )</h3>
		<p>Pre-multiplies this matrix by [page:Matrix3 m].</p>

		<h3>[method:this setFromMatrix4]( [param:Matrix4 m] )</h3>
		<p>
			Set this matrix to the upper 3x3 matrix of the Matrix4 [page:Matrix4 m].
		</p>

		<h3>
			[method:this setUvTransform]( [param:Float tx], [param:Float ty], [param:Float sx], [param:Float sy], [param:Float rotation], [param:Float cx], [param:Float cy] )
		</h3>
		<p>
			[page:Float tx] - offset x<br />
			[page:Float ty] - offset y<br />
			[page:Float sx] - repeat x<br />
			[page:Float sy] - repeat y<br />
			[page:Float rotation] - rotation, in radians. Positive values rotate
			counterclockwise<br />
			[page:Float cx] - center x of rotation<br />
			[page:Float cy] - center y of rotation<br /><br />

			Sets the UV transform matrix from offset, repeat, rotation, and center.
		</p>

		<h3>
			[method:Array toArray]( [param:Array array], [param:Integer offset] )
		</h3>
		<p>
			[page:Array array] - (optional) array to store the resulting vector in. If
			not given a new array will be created.<br />
			[page:Integer offset] - (optional) offset in the array at which to put the
			result.<br /><br />

			Writes the elements of this matrix to an array in
			[link:https://en.wikipedia.org/wiki/Row-_and_column-major_order#Column-major_order column-major] format.
		</p>

		<h3>[method:this translate]( [param:Float tx], [param:Float ty] )</h3>
		<p>Translates this matrix by the given scalar values.</p>

		<h3>[method:this transpose]()</h3>
		<p>
			[link:https://en.wikipedia.org/wiki/Transpose Transposes] this matrix in
			place.
		</p>

		<h3>[method:this transposeIntoArray]( [param:Array array] )</h3>
		<p>
			[page:Array array] - array to store the resulting vector in.<br /><br />

			[link:https://en.wikipedia.org/wiki/Transpose Transposes] this matrix into
			the supplied array, and returns itself unchanged.
		</p>

		<h2>Source</h2>

		<p>
			[link:https://github.com/mrdoob/three.js/blob/master/src/[path].js src/[path].js]
		</p>
	</body>
</html>