DOMMatrix (WebKitCSSMatrix) - Web APIs 编辑

The DOMMatrix interface represents 4×4 matrices, suitable for 2D and 3D operations including rotation and translation. It is a mutable version of the DOMMatrixReadOnly interface.

WebKitCSSMatrix is an alias to DOMMatrix.

This interface should be available inside web workers, though some implementations don't allow it yet.

Constructor

DOMMatrix()

Creates and returns a new DOMMatrix object.

Properties

This interface inherits properties from DOMMatrixReadOnly, though some of these properties are altered to be mutable.

is2D Read only

A Boolean flag whose value is true if the matrix was initialized as a 2D matrix. If false, the matrix is 3D.

isIdentity Read only

A Boolean whose value is true if the matrix is the identity matrix. The identity matrix is one in which every value is 0 except those on the main diagonal from top-left to bottom-right corner (in other words, where the offsets in each direction are equal).

m11, m12, m13, m14, m21, m22, m23, m24, m31, m32, m33, m34, m41, m42, m43, m44

Double-precision floating-point values representing each component of a 4×4 matrix, where m11 through m14 are the first column, m21 through m24 are the second column, and so forth.

a, b, c, d, e, f

Double-precision floating-point values representing the components of a 4×4 matrix which are required in order to perform 2D rotations and translations. These are aliases for specific components of a 4×4 matrix, as shown below.

2D	3D equivalent
a	m11
b	m12
c	m21
d	m22
e	m41
f	m42

Methods

This interface includes the following methods, as well as the methods it inherits from DOMMatrixReadOnly.

DOMMatrix.invertSelf()

Modifies the matrix by inverting it. If the matrix can't be inverted, its components are all set to NaN, and is2D returns false.

DOMMatrix.multiplySelf()

Modifies the matrix by post-multiplying it with the specified DOMMatrix. This is equivalent to the dot product A⋅B, where matrix A is the source matrix and B is the matrix given as an input to the method. Returns itself.

DOMMatrix.preMultiplySelf()

Modifies the matrix by pre-multiplying it with the specified DOMMatrix. This is equivalent to the dot product B⋅A, where matrix A is the source matrix and B is the matrix given as an input to the method. Returns itself.

DOMMatrix.translateSelf()

Modifies the matrix by applying the specified vector. The default vector is [0, 0, 0]. Returns itself.

DOMMatrix.scaleNonUniformSelf()

Modifies the matrix by applying the specified scaling on the X, Y, and Z axes, centered at the given origin. By default, the Y and Z axes' scaling factors are both 1, but the scaling factor for X must be specified. The default origin is (0, 0, 0). Returns itself.

DOMMatrix.scaleSelf()

Modifies the matrix by applying the specified scaling factors, with the center located at the specified origin. Also returns itself. By default, the scaling factor is 1 for all three axes, and the origin is (0, 0, 0). Returns itself.

DOMMatrix.scale3dSelf()

Modifies the matrix by applying the specified scaling factor to all three axes, centered on the given origin. Returns itself.

DOMMatrix.rotateSelf()

Modifies the matrix by rotating itself around each axis by the specified number of degrees. Returns itself.

DOMMatrix.rotateAxisAngleSelf()

Modifies the matrix by rotating it by the specified angle around the given vector. Returns itself.

DOMMatrix.rotateFromVectorSelf()

Modifies the matrix by rotating it by the angle between the specified vector and (1, 0). Returns itself.

DOMMatrix.setMatrixValue()

Replaces the contents of the matrix with the matrix described by the specified transform or transforms. Returns itself.

DOMMatrix.skewXSelf()

Modifies the matrix by applying the specified skew transformation along the X-axis. Returns itself.

DOMMatrix.skewYSelf()

Modifies the matrix by applying the specified skew transformation along the Y-axis. Returns itself.

Static methods

This interface inherits methods from DOMMatrixReadOnly.

fromFloat32Array()

Creates a new mutable DOMMatrix object given an array of single-precision (32-bit) floating-point values. If the array has six values, the result is a 2D matrix; if the array has 16 values, the result is a 3D matrix. Otherwise, a TypeError exception is thrown.

fromFloat64Array()

Creates a new mutable DOMMatrix object given an array of double-precision (64-bit) floating-point values. If the array has six values, the result is a 2D matrix; if the array has 16 values, the result is a 3D matrix. Otherwise, a TypeError exception is thrown.

fromMatrix()

Creates a new mutable DOMMatrix object given an existing matrix or a DOMMatrixInit dictionary which provides the values for its properties.

Usage notes

The matrix defined by the DOMMatrix interface is comprised of four rows of four columns each. While it's beyond the scope of this article to explain the mathematics involved, this 4×4 size is enough to describe any transformation you might apply to either 2D or 3D geometries.

The DOMMatrix interface is designed with the intent that it will be used for all matrices within markup, supplanting the SVGMatrix and CSSMatrix interfaces.

Specifications

Browser compatibility

BCD tables only load in the browser

BCD tables only load in the browser

See also

• Its non-modifiable counterpart, DOMMatrixReadOnly
• SVGMatrix, the SVG matrix intended to be superseded by DOMMatrix