DOMMatrixReadOnly: fromMatrix() static method

Syntax

DOMMatrixReadOnly.fromMatrix()
DOMMatrixReadOnly.fromMatrix(other)

Parameters

other Optional

A DOMMatrix, DOMMatrixReadOnly, or an object with the same properties. All properties default to 0. The properties are:

is2D

A boolean. true if the matrix should be created as a 2D matrix. Defaults to false if at least one of m13, m14, m23, m24, m31, m32, m34, or m43 is non-zero, or at least one of m33 or m44 is not 1; otherwise, defaults to true.

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

Numbers 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. m11, m22, m33, and m44 default to 1, and all other components default to 0.

If is2D is explicitly set to true, m13, m14, m23, m24, m31, m32, m34, or m43 must either be omitted or set to 0, and m33 and m44 must either be omitted or set to 1.

a, b, c, d, e, f

Aliases for m11, m12, m21, m22, m41, and m42, respectively, for convenience when initializing 2D matrices. If these aliases are provided with the m counterparts, their values must be equal.

Return value

A DOMMatrixReadOnly object.

Exceptions

TypeError

Thrown if the provided object's properties are inconsistent (for example, if both a and m11 are provided but have different values).

Examples

Creating a matrix from an object

This example creates a DOMMatrixReadOnly by providing matrix values in an object.

const matrix = DOMMatrixReadOnly.fromMatrix({
  a: 1,
  b: 0,
  c: 0,
  d: 1,
  e: 50,
  f: 50,
  is2D: true,
});

console.log(matrix.toString());
// Output: matrix(1, 0, 0, 1, 50, 50)

console.log(matrix.is2D);
// Output: true

Creating a matrix from an existing matrix

This example creates a new DOMMatrixReadOnly from an existing DOMMatrixReadOnly.

const matrix1 = new DOMMatrixReadOnly([1, 0, 0, 1, 100, 100]);
const matrix2 = DOMMatrixReadOnly.fromMatrix(matrix1);

console.log(matrix2.toString());
// Output: matrix(1, 0, 0, 1, 100, 100)

Creating a default identity matrix

This example shows how calling fromMatrix() with no arguments creates an identity matrix.

const identityMatrix = DOMMatrixReadOnly.fromMatrix();

console.log(identityMatrix.toString());
// Output: matrix(1, 0, 0, 1, 0, 0)

console.log(identityMatrix.isIdentity);
// Output: true

Specifications

Browser compatibility

See also

• DOMMatrixReadOnly() constructor
• DOMMatrixReadOnly.fromFloat32Array()
• DOMMatrixReadOnly.fromFloat64Array()