DOMMatrixReadOnly: rotateFromVector() method

Note: This feature is available in Web Workers.

The rotateFromVector() method of the DOMMatrixReadOnly interface is returns a new DOMMatrix created by rotating the source matrix by the angle between the specified vector and (1, 0). The rotation angle is determined by the angle between the vector (1,0)T and (x,y)T in the clockwise direction, or (+/-)arctan(y/x). If x and y are both 0, the angle is specified as 0. The original matrix is not altered.

To mutate the matrix as you rotate it by the angle between the specified vector and (1, 0), see DOMMatrix.rotateFromVectorSelf().

Syntax

js
rotateFromVector()
rotateFromVector(rotX)
rotateFromVector(rotX, rotY)

Parameters

rotX Optional

A number; the x-coordinate of the x,y vector that determines the rotation angle. If undefined, 0 is used.

rotY Optional

A number; the y-coordinate of the x,y vector that determines the rotation angle. If undefined, 0 is used.

Return value

A DOMMatrix.

Examples

js
const matrix = new DOMMatrix(); // create a matrix
console.log(matrix.toString()); // original value
// output: "matrix(1, 0, 0, 1, 0, 0)"

console.log(matrix.rotateFromVector().toString()); // defaults to `0`
// output: matrix(1, 0, 0, 1, 0, 0)

console.log(matrix.rotateFromVector(10, 20).toString());
// matrix(0.447, 0.894, -0.894, 0.447, 0, 0)

console.log(matrix.rotateFromVector(-5, 5).toString());
// matrix(-0.707, 0.707, -0.707, -0.707, 0, 0)

console.log(matrix.toString()); // matrix remains unchanged
// output: "matrix(1, 0, 0, 1, 0, 0)"

Specifications

See also