method DOMMatrix.rotateFromVectorSelf

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.

MDN Reference