Please note that this function is only needed when working with dynamic apodization.
This function computes a dynamic symmetric Hanning window which returns for every virtual source whether or not the values are considered in the aperture or not. In the case of Plane Wave, these values are computed for reception for every transducer, whereas for Synthetic Aperture they are computed once per line for the transmitter and for every transducer in reception. The function is dependent on the result of Focusing and Image Points. The other values on which the computation of the dynamic apodization is dependent on are the F number, the direction of propagation and the apodization reference (same as per Delay).