1PLOTIF(3NCARG) NCAR GRAPHICS PLOTIF(3NCARG)
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6 PLOTIF - A line-drawing routine, described in terms of "pen moves".
7 Most calls to PLOTIF specify whether the "pen" should be up (not
8 drawing) or down (drawing) and then move it to a designated position in
9 the fractional coordinate system. The polylines resulting from the pen
10 moves are buffered; some calls to PLOTIF just cause the SPPS polyline
11 buffer to be flushed.
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14 CALL PLOTIF (FX,FY,IP)
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17 #include <ncarg/ncargC.h>
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19 void c_plotif (float fx, float fy, int ip)
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22 FX (an input expression of type REAL) is the X fractional
23 coordinate of the point to which the plotter pen is to be
24 moved. If IP = 2, this argument is ignored.
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26 FY (an input expression of type REAL) is the Y fractional
27 coordinate of the point to which the plotter pen is to be
28 moved. If IP = 2, this argument is ignored.
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30 IP (an input expression of type INTEGER) determines whether
31 the movement of the plotter pen to the point (FX,FY) will
32 occur with the pen up (IP = 0), or with the pen down (IP =
33 1). If IP = 2, no pen move occurs, but the SPPS polyline
34 buffer is flushed.
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37 The C-binding argument descriptions are the same as the FORTRAN
38 argument descriptions.
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41 "CALL PLOTIF (FX,FY,0)" moves the pen to a new starting position.
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43 "CALL PLOTIF (FX,FY,1)" moves the pen to a new position, drawing a
44 straight line segment from the previous position to the new one.
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46 "CALL PLOTIF (0.,0.,2)" flushes the SPPS polyline buffer.
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48 The size of the SPPS polyline buffer can be changed by calling the
49 parameter-setting routine SETUSV to set the parameter 'PB'. The legal
50 range of 'PB' is between 2 and 50. For example, to set 'PB' to 2, use
51 "CALL SETUSV ('PB',2)".
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53 NOTE!
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55 The SPPS polyline buffer is provided to increase drawing efficiency.
56 However, there are side effects that can occur because the polyline
57 segments get buffered. For example, if one wanted to change the color
58 of a line at a certain point, one would have to remember to flush the
59 buffer before calling GSPLCI to change the polyline color index. This
60 applies to the changing of any polyline attribute.
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63 Use the ncargex command to see the following relevant examples: arex01,
64 cbex01, cmppos, coex03, cpexcc, epltch.
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67 To use PLOTIF or c_plotif, load the NCAR Graphics libraries ncarg,
68 ncarg_gks, and ncarg_c, preferably in that order.
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71 Online: gpl, plotit, setusv, getusv, sflush, frstpt, vector, line,
72 curve, spps, spps_params, ncarg_cbind
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74 Hardcopy: NCAR Graphics Fundamentals, UNIX Version; User's Guide for
75 NCAR GKS-0A Graphics
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78 Copyright (C) 1987-2009
79 University Corporation for Atmospheric Research
80 The use of this Software is governed by a License Agreement.
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84UNIX March 1993 PLOTIF(3NCARG)