1Dashline_params(3NCARG) NCAR GRAPHICS Dashline_params(3NCARG)
2
6 Dashline_params - Brief descriptions of all internal parameters of
7 Dashline.
8
10 No parameter-access routines are available for the utility Dashline.
11 Parameters are set through the common blocks SMFLAG, INTPR, and DASHD1.
12 There are four different versions of Dashline: normal, quick, smooth,
14 and super. Which version is used depends on options used on the
15 ncargf77 command line. The lines drawn by the different versions can
16 vary considerably in appearance.
17 The following set of common blocks may be used to access any of the
19 internal parameters of the Dashline utility:
20 COMMON /SMFLAG/ IOFFS
23 COMMON /INTPR / IPAU,FPART,TENSN,NP,SMALL,L1,ADDLR,ADDTB,MLLINE,
25 + ICLOSE
26 COMMON /DASHD1/ ISL,L,ISIZE,IP(100),NWDSM1,IPFLAG(100),MNCSTR,IGP
28 The following table indicates which of the internal parameters affect
30 the behavior of the various versions of Dashline ("Y" indicates an
31 effect, "N" indicates no effect):
32 Parameter QUICK NORMAL SMOOTH SUPER
36 --------- ----- ------ ------ -----
37 ADDLR N N N Y
38 ADDTB N N N Y
39 FPART N Y Y Y
40 ICLOSE Y Y Y Y
41 IGP N Y Y Y
42 IOFFS N N Y Y
43 IPAU Y Y Y Y
44 L1 N N Y Y
45 MLLINE N N N Y
46 NP N N Y Y
47 SMALL N N Y Y
48 TENSN N N Y Y
49 PARAMETER DESCRIPTIONS
51 ADDLR The amount of free space to be left on the left and on the
53 right of each character string, stated as the desired
54 number of NDCs (Normalized Device Coordinates) times 1023.
55 This only affects the "super" version of Dashline; it
56 changes the size of the area marked around a label in the
57 bit map that is used for culling crowded lines. [Default =
58 2. (2./1023. NDCs)]
59 ADDTB The amount of free space to be left on the top and on the
61 bottom of each character string, stated as the desired
62 number of NDCs (Normalized Device Coordinates) times 1023.
63 This only affects the "super" version of Dashline; it
64 changes the size of the area marked around a label in the
65 bit map that is used for culling crowded lines. [Default =
66 2. (2./1023. NDCs)]
67 FPART A multiplication factor for the length of the first solid
69 line segment on any curve. This can be used to offset
70 labels. For example, if FPART = .5, the first solid line
71 segment is only one-half as long as the other solid line
72 segments. This will move all labels on the current curve
73 towards the beginning of the curve and thereby reduce the
74 probability of a label being written on top of a label on a
75 nearby curve drawn with FPART = 1. [Default = 1.]
76 ICLOSE An internal or external call to move the "drawing pen"
78 (pen-up) to a specific position is executed only if the
79 position is more than ICLOSE units away from the current
80 pen position (the distance is measured as the absolute
81 difference in X-coordinates plus the absolute difference in
82 Y-coordinates). The unit of measurement is 32767 integer
83 units in each of the X and Y dimensions. [Default = 6]
84 IGP Flag to control whether gaps are left for labels along a
86 curve. If no gaps are left, the labels don't look as good,
87 but you can be sure of what the curve is doing in the
88 regions occupied by the labels.
89 9 A gap is left.
91 0 No gap is left.
93 [Default = 9]
95 IOFFS Flag used to turn smoothing off.
97 0 Smoothing.
99 1 No smoothing.
101 [Default = 0]
103 IPAU The length of the gap or solid line associated with each
105 element of a dash pattern defined by a call to DASHDB,
106 given as the desired value in NDCs (Normalized Device
107 Coordinates) times 1023. Such a dash pattern is repeated
108 approximately every REAL(IPAU)/64. NDC units along the
109 length of a curve. [Default = 3 (3./1023. NDCs)]
110 L1 The maximum number of points to be saved at one time. If
112 there are more than L1 points on a given line, L1 points
113 are processed, then the next L1, and so on, until the
114 entire line is processed. Smoothness between segments is
115 maintained automatically. If L1 is increased, the
116 dimensions of XSAVE, YSAVE, XP, YP, TEMP, and SLEN in the
117 routine FDVDLD must be increased to the new value of L1.
118 [Default = 70]
119 MLLINE The maximum length in either coordinate of a single line
121 segment to be processed by the crowded line algorithm.
122 Line segments longer than MLLINE units in either coordinate
123 are broken into smaller segments, each of which is
124 processed separately. This is done to prevent anomalies in
125 the removal of long line segments, since only the starting
126 point and end point of each line segment is checked in that
127 process. The unit of measurement is 32767 integer units in
128 each of the X and Y dimensions. [Default = 384]
129 NP Determines how many points are used to draw each smoothed
131 curve. The value of NP is twice the maximum number of
132 interpolated points on a horizontal curve with length equal
133 to that of the width of the grid. More points per unit
134 length are interpolated for short lines than for long
135 lines. [Default = 150]
136 SMALL When the points on a line are being processed, only the
138 first of two consecutive points is saved if the points are
139 less than SMALL units apart. This procedure is to prevent
140 cusps. The unit of measurement is 32767 integer units in
141 each of the X and Y dimensions. [Default = 128.]
142 TENSN Tension factor. Must be greater than 0. A large tension
144 factor (30.) would essentially turn off smoothing.
145 [Default = 2.5]
146
148 Online: dashline, curved, dashdb, dashdc, frstd, lastd, lined, reset,
149 vectd, ncarg_cbind
150 Hardcopy: NCAR Graphics Contouring and Mapping Tutorial; NCAR Graphics
152 Fundamentals, UNIX Version; User's Guide for NCAR GKS-0A Graphics
153
155 Copyright (C) 1987-2007
156 University Corporation for Atmospheric Research
157 This documentation is free software; you can redistribute it and/or
159 modify it under the terms of the GNU General Public License as
160 published by the Free Software Foundation; either version 2 of the
161 License, or (at your option) any later version.
162 This software is distributed in the hope that it will be useful, but
164 WITHOUT ANY WARRANTY; without even the implied warranty of
165 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
166 General Public License for more details.
167 You should have received a copy of the GNU General Public License along
169 with this software; if not, write to the Free Software Foundation,
170 Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
171UNIX March 1993 Dashline_params(3NCARG)