twStoreShadowArea( sT, sL, sB, sR, tShadow,;
                    vShadow, hShadow )
 ----------------------------------------------------------------------------
     Store a screen region to be used for a shadow to two variables
     which are passed by reference. This function cane be used in
     creating your own additions to TSDWIN.  ALL parameters MUST be
     passed!

       Arguments:

     sT,sL
     sB,sR   - 'N' The coordinates of the underlying screen area around
                   which the shadow is to be placed.

     tShadow - 'N' Shadow Type.

     vShadow - 'C' String to hold vertical shadow area information.
                   MUST be passed by reference.

     hShadow - 'C' String to hold horizontal shadow area information.
                   MUST be passed by reference.

       Return:

     Current Window Handle.

       Example:

     twStoreShadowArea( sT, sL, sB, sR, tShadow, @vShadow, @hShadow )