DOMMatrixReadOnly: toFloat32Array() method

The toFloat32Array() method of the DOMMatrixReadOnly interface returns a new Float32Array containing all 16 elements (m11, m12, m13, m14, m21, m22, m23, m24, m31, m32, m33, m34, m41, m42, m43, m44) which comprise the matrix. The elements are stored into the array as single-precision floating-point numbers in column-major (colexographical access, or "colex") order. (In other words, down the first column from top to bottom, then the second column, and so forth.)

For double-precision floating-point numbers, see DOMMatrixReadOnly.toFloat64Array().

Syntax

toFloat32Array()

Parameters

None.

Return value

A Float32Array; an array of the matrix's 16 element values.

Examples

Basic usage

const matrix = new DOMMatrixReadOnly();
const float32 = matrix.translate(20, 30, 50).toFloat32Array();
console.log(float32); // Float64Array(16) [ 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 20, 30, 0, 1 ] ]
console.log(`m41: ${float32[12]}, m42: ${float32[13]}, m43: ${float32[14]}`); // m41: 20, m42: 30, M44: 40

Single precision

There are multiple ways to access the values of a matrix. This example rotates a matrix by 30deg, saving the rotated state as a JSON object using the DOMMatrixReadOnly.toJSON() method and as a single-precision array using the toFloat32Array() method.

const matrix = new DOMMatrixReadOnly();
const json = matrix.rotate(30).toJSON();
const float32 = matrix.rotate(30).toFloat32Array();

console.log(`a: ${json["a"]}, b: ${json["b"]}`); // a: 0.8660254037844387, b: 0.49999999999999994
console.log(`a: ${float32[0]}, b: ${float32[1]}`); // a: 0.8660253882408142, b: 0.5

Specifications

Browser compatibility

See also

• DOMMatrixReadOnly.toFloat64Array()
• DOMMatrix.setMatrixValue()