DOMMatrix: rotateFromVectorSelf() method

Note: This feature is available in Web Workers.

The rotateFromVectorSelf() method of the DOMMatrix interface is a mutable transformation method that modifies a matrix by rotating the 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, and the matrix is not altered.

To rotate a matrix from a vector without mutating it, see DOMMatrixReadOnly.rotateFromVector(), which creates a new rotated matrix while leaving the original unchanged.

Syntax

js
rotateFromVectorSelf()
rotateFromVectorSelf(rotX)
rotateFromVectorSelf(rotX, rotY)

Parameters

rotX Optional

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

rotY Optional

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

Return value

Returns itself; the updated DOMMatrix.

Examples

js
const matrix = new DOMMatrix(); // create a matrix
console.log(matrix.rotateFromVectorSelf().toString());
// output: matrix(1, 0, 0, 1, 0, 0) (no rotation applied)
console.log(matrix.rotateFromVectorSelf(10, 20).toString());
// output: matrix(0.447, 0.894, -0.894, 0.447, 0, 0)
console.log(matrix.toString());
// output: matrix(0.447, 0.894, -0.894, 0.447, 0, 0) (same as above)

Specifications

See also