The GBLKVPD subroutine is a graphical call that deletes and releases the current blanking area. It enables graphics output to be drawn in the area previously blanked out by a call to the GBLKVP subroutine . This call is part of the traditional graphics subsystem, which is no longer being developed.
To release an area previously blanked out, as in the example for the GBLKVP subroutine , use the following statement.
/* define blanking viewport */
call gblkvp({20 20, 80 80});
/* more graphics statements... */
/* now release the blanked out area */
call gblkvpd;
/* graphics or text can now be written to the area */
/* continue graphics statements... */
See also the description of the CLIP option in the RESET statement .