DOMMatrixReadOnly: toFloat32Array() method
Baseline Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since January 2020.
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
DOMMatrixReadOnly.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
Specification |
---|
Geometry Interfaces Module Level 1 # dom-dommatrixreadonly-tofloat32array |
Browser compatibility
BCD tables only load in the browser