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.