  plfill(n, x, y)
  ***************

  plfill

  Fills the polygon defined by the n points (x[i], y[i]) using the pattern
  defined by plpsty or plpat. The routine will automatically close the
  polygon between the last and first vertices. If multiple closed polygons
  are passed in x and y then plfill will fill in between them.

  n (PLINT, input): Number of vertices in polygon.

  x (PLFLT *, input): Pointer to array with x coordinates of vertices.

  y (PLFLT *, input): Pointer to array with y coordinates of vertices.

