method DOMMatrixReadOnly.rotateFromVector

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.

MDN Reference