gsepik

Purpose

     Defines the beginning delimiter for a group of GSL output
     primitive functions.

C Syntax

     int gsepik_ (pickwind)

     int *pickwind;

FORTRAN Syntax

     INTEGER function gsepik (pickwind)

     INTEGER pickwind

Pascal Syntax

     FUNCTION gsepik_ (

     VAR pickwindow : INTEGER
     ): INTEGER [PUBLIC|;

Description

     The gsepik subroutine defines the opening delimiter for a
     group of output routines.   The GSL output functions that
     occur  after this  command cause  a pick  input from  the
     display adapter for each intersection of a vertex and the
     pick aperture  window centered  about the  current cursor
     position.

     The pick  input is placed  on the user input  ring, indi-
     cating the count  of output functions since  the start of
     the pick.   The input  also indicates  the center  of the
     pick window in x,y coordinates.

     The gsepik subroutine  is provided only for  use with the
     IBM 5081 Display, and not for use with other displays.

     See "gsdpik" and -- Spot  'output' unknown -- for related
     information.

     Parameters

     pickwind  Defines a pick window  center about the current
               cursor  position.  Valid  values are  between 1
               and the maximum cursor size.

     A cursor must be defined and visible for the gsepik func-
     tion to operate.

     Processing of  the SIGRETRACT  signal is  suspended until
     the completion of the pick  function with the gsdpik sub-
     routine.

Return Value

     GS_SUCC   Successful.
     GS_NCOR   Undefined cursor.
     GS_CURV   Cursor not visible.
     GS_IVWD   Invalid pick window size.
     GS_USUC   Unsuccessful.

Related Information

     In this book:  "gsdpik" and -- Spot 'output' unknown --.