/** * Get the value of this quaternion as an axis-angle value. * * @param aa The axis angle object to put the converted values into */ public void get(AxisAngle4d aa) { double d = x * x + y * y + z * z; if (d > EPSILON) { d = Math.sqrt(d); double inv_d = 1 / d; aa.x = x * inv_d; aa.y = y * inv_d; aa.z = z * inv_d; aa.angle = 2 * Math.atan2(d, angle); } else { aa.x = 0.0f; aa.y = 1.0f; aa.z = 0.0f; aa.angle = 0.0f; } }