yawAngle
The yaw angle of the face specified in degrees.
Declaration
var yawAngle: CGFloat { get }Discussion
The yaw angle represents the rotation of the face around the vertical axis. A value of 0.0 yields a face that is looking directly at the camera, whereas a yaw angle of 90 degrees yields a face whose eye line is perpendicular to that of the camera.
You must check the value of the hasYawAngle property before accessing this property. If the value in the hasYawAngle property is false, reading the value in this property raises an exception.