%N pglcur %F $MIR/src/pglcur.f
%D Draw a line using the cursor
%B
      SUBROUTINE PGLCUR (MAXPT, NPT, X, Y)
      INTEGER MAXPT, NPT
      REAL    X(*), Y(*)

 Interactive routine for user to enter a polyline by use of
 the cursor.  Routine allows user to Add and Delete vertices;
 vertices are joined by straight-line segments.

 Arguments:
  MAXPT  (input)  : maximum number of points that may be accepted.
  NPT    (in/out) : number of points entered; should be zero on
                    first call.
  X      (in/out) : array of x-coordinates (dimension at least MAXPT).
  Y      (in/out) : array of y-coordinates (dimension at least MAXPT).

 Notes:

 (1) On return from the program, cursor points are returned in
 the order they were entered. Routine may be (re-)called with points
 already defined in X,Y (# in NPT), and they will be plotted
 first, before editing.

 (2) User commands: the user types single-character commands
 after positioning the cursor: the following are accepted:
   A (Add)    - add point at current cursor location.
   D (Delete) - delete last-entered point.
   X (eXit)   - leave subroutine.
