NAME

       SFWRLD - The subroutines SFWRLD and SFNORM are used to fill that portion of the plotter frame inside the
       area defined by a given polygonal boundary.

SYNOPSIS

       CALL SFWRLD (XRA,YRA,NRA,DST,NST,IND,NND)

       CALL SFNORM (XRA,YRA,NRA,DST,NST,IND,NND)

C-BINDING SYNOPSIS

       #include <ncarg/ncargC.h>

       void c_sfwrld (float *xra, float *yra, int nra,
       float *dst, int nst, int *ind, int nnd)

       void c_sfnorm (float *xra, float *yra, int nra,
       float *dst, int nst, int *ind, int nnd)

DESCRIPTION

       XRA         (an  input/output  array  of  type  REAL,  dimensioned NRA) contains the X coordinates of the
                   points defining the area to be filled, in the user coordinate system (if SFWRLD is called) or
                   in the fractional coordinate system (if SFNORM is  called).  Upon  return  from  SFWRLD,  the
                   contents of XRA will have been converted to the fractional coordinate system.

       YRA         (an  input/output  array  of  type  REAL,  dimensioned NRA) contains the Y coordinates of the
                   points defining the area to be filled, in the user coordinate system (if SFWRLD is called) or
                   in the fractional coordinate system (if SFNORM is  called).  Upon  return  from  SFWRLD,  the
                   contents of YRA will have been converted to the fractional coordinate system.

       NRA         (an input expression of type INTEGER) is the number of points defining the area to be filled.
                   NRA must be greater than two.

       DST(NST)    (a scratch array of type REAL, dimensioned NST or greater) is for use by the fill algorithm.

       NST         (an input expression of type INTEGER) is the length of the array DST. It must be greater than
                   or  equal  to  NRA  + NIM, where NIM is the largest number of intersection points of any fill
                   line with the boundary lines. To be sure DST is large enough, use NIM = NRA; in practice, NIM
                   rarely needs to be that large.  For a convex polygon, for example, NIM = 2 suffices.

       IND         (a scratch array of type INTEGER, dimensioned  NND  or  greater)  is  for  use  by  the  fill
                   algorithm.

       NND         (an input expression of type INTEGER) is the length of the array IND. It must be greater than
                   or equal to NRA + 2 * NIM, where NIM is as defined above.

C-BINDING DESCRIPTION

       The C-binding argument descriptions are the same as the FORTRAN argument descriptions.

USAGE

       Both  SFWRLD  and  SFNORM  fill  the area defined by the points (XRA(I),YRA(I)), for I from 1 to NRA. The
       lines connecting point 1 to point 2, point 2 to point 3, ..., point NRA-1 to point NRA, and point NRA  to
       point  1  bound the area to be filled. The default values of SOFTFILL's internal parameters cause fill to
       be done with solid, horizontal lines .00125 normalized-device-coordinate units apart.

       Use SFWRLD if the arrays XRA and YRA contain world coordinates.   Use  SFNORM  if  XRA  and  YRA  contain
       normalized  device  coordinates. Since SFWRLD transforms XRA and YRA from world coordinates to normalized
       device coordinates, any subsequent calls with those arrays should be to SFNORM (for example, to create  a
       cross-hatched effect).

EXAMPLES

       Use  the  ncargex  command  to  see  the  following relevant examples: cmptit, agex12,    cpex01, cpex02,
       cpex03, sfex01, vvex01, tsoftf, fsfwrld.

ACCESS

       To use SFWRLD, SFNORM, c_sfwrld, or c_sfnorm, load the NCAR  Graphics  libraries  ncarg,  ncarg_gks,  and
       ncarg_c, preferably in that order.  in that order.

MESSAGES

       See the softfill man page for a description of all Softfill error messages and/or informational messages.

SEE ALSO

       Online:  softfill,  softfill_params,  sfgetc,  sfgeti,  sfgetp,  sfgetr,  sfsetc, sfseti, sfsetp, sfsetr,
       sfsgfa, ncarg_cbind

       Hardcopy: NCAR Graphics Fundamentals, UNIX Version

COPYRIGHT

       Copyright (C) 1987-2009
       University Corporation for Atmospheric Research
       The use of this Software is governed by a License Agreement.

UNIX                                               March 1993                                     SFWRLD(3NCARG)