imageRotationReference

eyeDistanceScaling Sets the type of rotation to apply if the Placemark.imageRotation is not zero. This value indicates whether to apply this placemark's image rotation relative to the screen or the globe.
If OrientationMode.RELATIVE_TO_SCREEN, this placemark's image is rotated in the plane of the screen and its orientation relative to the globe changes as the view changes. If OrientationMode.RELATIVE_TO_GLOBE, this placemark's image is rotated in a plane tangent to the globe at this placemark's position and retains its orientation relative to the globe.