bionic (3) plotif.3NCARG.gz

NAME

       PLOTIF - A line-drawing routine, described in terms of "pen moves".  Most calls to PLOTIF specify whether
       the "pen" should be up (not drawing) or down (drawing) and then move it to a designated position in the
       fractional coordinate system.  The polylines resulting from the pen moves are buffered; some calls to
       PLOTIF just cause the SPPS polyline buffer to be flushed.

SYNOPSIS

       CALL PLOTIF (FX,FY,IP)

C-BINDING SYNOPSIS

       #include <ncarg/ncargC.h>

       void c_plotif (float fx, float fy, int ip)

DESCRIPTION

       FX          (an input expression of type REAL) is the X fractional coordinate of the point to which the
                   plotter pen is to be moved.  If IP = 2, this argument is ignored.

       FY          (an input expression of type REAL) is the Y fractional coordinate of the point to which the
                   plotter pen is to be moved.  If IP = 2, this argument is ignored.

       IP          (an input expression of type INTEGER) determines whether the movement of the plotter pen to
                   the point (FX,FY) will occur with the pen up (IP = 0), or with the pen down (IP = 1).  If IP
                   = 2, no pen move occurs, but the SPPS polyline buffer is flushed.

C-BINDING DESCRIPTION

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

USAGE

       "CALL PLOTIF (FX,FY,0)" moves the pen to a new starting position.

       "CALL PLOTIF (FX,FY,1)" moves the pen to a new position, drawing a straight line segment from the
       previous position to the new one.

       "CALL PLOTIF (0.,0.,2)" flushes the SPPS polyline buffer.

       The size of the SPPS polyline buffer can be changed by calling the parameter-setting routine SETUSV to
       set the parameter 'PB'.  The legal range of 'PB' is between 2 and 50.  For example, to set 'PB' to 2, use
       "CALL SETUSV ('PB',2)".

       NOTE!

       The SPPS polyline buffer is provided to increase drawing efficiency.  However, there are side effects
       that can occur because the polyline segments get buffered.  For example, if one wanted to change the
       color of a line at a certain point, one would have to remember to flush the buffer before calling GSPLCI
       to change the polyline color index.  This applies to the changing of any polyline attribute.

EXAMPLES

       Use the ncargex command to see the following relevant examples: arex01, cbex01, cmppos, coex03, cpexcc,
       epltch.

ACCESS

       To use PLOTIF or c_plotif, load the NCAR Graphics libraries ncarg, ncarg_gks, and ncarg_c, preferably in
       that order.

SEE ALSO

       Online: gpl, plotit, setusv, getusv, sflush, frstpt, vector, line, curve, spps, spps_params, ncarg_cbind

       Hardcopy: NCAR Graphics Fundamentals, UNIX Version; User's Guide for NCAR GKS-0A Graphics

COPYRIGHT

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