1Dashpack_params(3NCARG) NCAR GRAPHICS Dashpack_params(3NCARG)
2
6 Dashpack_params - This document briefly describes all Dashpack
7 parameters.
8
10 Dashpack has twenty internal parameters that affect what it does. The
11 current value of a parameter may be retrieved by calling one of the
12 routines DPGETC, DPGETI or DPGETR. A parameter may be given a new
13 value by calling one of the routines DPSETC, DPSETI, or DPSETR.
14 The Dashpack parameter descriptions appear below in alphabetical order.
16 Each description begins with a line giving the parameter name and the
17 intrinsic FORTRAN type of the parameter.
18 'CRB' - Character
20 Character Representing a Break: the single character that is to
22 be used in a label string in a character dash pattern to
23 represent a break point in the label string. (Each piece of the
24 label string is written using a separate call to PLCHHQ, PLCHMQ,
25 or PLCHLQ; the effect is to make the label "bend" with the curve
26 that it labels.)
27 The default value of 'CRB' is a vertical bar.
29 'CRG' - Character
31 Character Representing a Gap: the single character that is to be
33 used in a character dash pattern to represent a gap (of width
34 'WOG') in the curve.
35 The default value of 'CRG' is an underscore.
37 'CRS' - Character
39 Character Representing a Solid: the single character that is to
41 be used in a character dash pattern to represent a solid section
42 (of width 'WOS') of the curve.
43 The default value of 'CRS' is a dollar sign.
45 'DPL' - Integer
47 Dash Pattern Length: the length of the character-string value of
49 the internal parameter 'DPT', as set by DPSETC or by a
50 subsequent call to DPSETI or DPSETR. Calling DPSETC with first
51 argument 'DPT' sets both 'DPT', which is the character dash
52 pattern, and 'DPL', which is its length; 'DPL' can later be
53 reset (normally to a smaller value) by a subsequent call to
54 DPSETI or DPSETR with first argument 'DPL', thus requesting the
55 use of a different number of characters of the specified dash
56 pattern.
57 The value of 'DPL' must be between 1 and 256.
59 The default value is 16.
61 'DPS' - Integer
63 Dash Pattern Selector: selects the dash pattern to be used.
65 A negative value of 'DPS' says that the integer dash pattern (as
67 specified by a call to DPSETI or DPSETR with first argument
68 'DPT') is to be used. If the absolute value is "n", then the
69 low-order "n" bits of the integer are used as the dash pattern.
70 No more than 32 bits of an integer dash pattern may be used;
71 using more than 24 may be a problem on some systems.
72 A positive value of 'DPS' says that the current character dash
74 pattern (as specified by a call to DPSETC with first argument
75 'DPT') is to be used; 'DPS' = 0 says to use the first 'DPL'
76 characters of the dash pattern, while 'DPS' > 0 says to use the
77 first 'DPS' characters of the dash pattern. No more than 256
78 characters of a character dash pattern may be used.
79 The value of 'DPS' must be between -32 and +256.
81 The default value is 0.
83 'DPT' - Character or Integer
85 Dash PaTtern: one of the current dash patterns. (In a call to
87 DPSETC or DPGETC, the name 'DPT' refers to the current
88 character-string dash pattern, but in a call to DPSETI, DPGETI,
89 DPSETR, or DPGETR, it refers to the current integer dash
90 pattern. Which of these is actually in use at a given time is
91 specified by the value of the internal parameter 'DPS'.)
92 In an integer dash pattern, 1 bits represent solids and 0 bits
94 represent gaps. No more than 32 bits of an integer dash pattern
95 may be used; using more than 24 bits may be a problem on some
96 systems.
97 A character dash pattern is a string of 256 or fewer characters;
99 in such a string, occurrences of the characters specified by the
100 values of 'CRG' and 'CRS' specify gaps and solids, respectively.
101 Other characters in the dash pattern form label strings to be
102 written along a curve. Within each complete label string of a
103 character dash pattern, the character specified by the value of
104 'CRB' may be used to specify "break points" at which the label
105 string may be broken into smaller substrings. Alternatively, the
106 single-character flag 'SCF' may be set non-zero to say that the
107 label string may be broken into single-character substrings.
108 Since each such substring is written by a separate call to
109 PLCHHQ, PLCHMQ, or PLCHLQ, the effect of breaking up a label
110 string is to make the label "bend" with the curve.
111 The default character dash pattern consists of sixteen dollar
113 signs, and the default integer dash pattern is "65535", which
114 has sixteen low-order 1s.
115 'EPS' - Real
117 EPSilon: says how far apart two points have to be (in X or Y, in
119 the fractional coordinate system) in order to be considered
120 separate points by the smoothing routine DPSMTH.
121 The value of 'EPS' must be greater than or equal to zero.
123 The default value is .000001.
125 'LS1' - Real
127 Label Spacing parameter 1: specifies how much extra gap space to
129 leave at the beginning and end of a label. Giving 'LS1' a non-
130 zero value helps to ensure that there will be a sufficiently
131 large gap to (for example) prevent a leading minus sign from
132 appearing to be part of the line.
133 The value of 'LS1' is given as a multiple of the value of the
135 parameter 'WOC' (the width of a character); it must not be less
136 than zero nor greater than 10.
137 The default value is .5.
139 'LS2' - Real
141 Label Spacing parameter 2: specifies how much extra gap space to
143 leave for each piece of a broken label. When break characters
144 are used or the single-character flag 'SCF' is turned on, 'LS2'
145 determines the spacing of the characters along the line.
146 The value of 'LS2' is given as a multiple of the value of the
148 parameter 'WOC' (the width of a character); it must not be less
149 than zero nor greater than 10.
150 The default value is 0.
152 'LTL' - Integer
154 Line Through Label: a flag that says whether or not each label
156 substring specified by a character dash pattern is to be written
157 in a gap ('LTL' = 0) or just on top of the curve ('LTL' = 1).
158 The latter is most effective if the line is one color and the
159 labels are another color.
160 The value of 'LTL' must be either 0 or 1.
162 The default value is 0.
164 'MFS' - Real
166 Multiplier for First Solid: a real multiplier for the length of
168 an initial solid portion of a curve drawn by DASHPACK. The
169 object of using this is to make it possible to slightly offset
170 labels on curves that are very nearly parallel to one another
171 (as can happen, for example, when drawing contour lines).
172 The value of 'MFS' must be greater than or equal to zero.
174 The default value is 1.
176 'PCF' - Integer
178 PlotChar Flag: says which PLOTCHAR routine is to be called to
180 draw character strings. The value 0 says to call PLCHHQ, the
181 value 1 says to call PLCHMQ, and the value 2 says to call
182 PLCHLQ.
183 The value of 'PCF" must be either 0, 1, or 2.
185 The default value is 0.
187 'SAF' - Real
189 String Angle Flag: says how labels are to be oriented.
191 If 'SAF' = 0, labels are written along a curve in the direction
193 in which the curve is being drawn.
194 If 'SAF' is negative, labels are written in the direction
196 ABS('SAF') degrees, but this is done only if 'LTL' is non-zero;
197 otherwise, the code behaves as if 'SAF' were zero: labels are
198 written in the direction of the curve.
199 If 'SAF' is greater than zero, labels are written along the
201 curve, but the angle is adjusted by adding multiples of 180
202 degrees so that the resulting angle lies in the range from
203 'SAF'-90 to 'SAF'+90 degrees.
204 If a label string is broken into substrings (either because
206 there are "break" characters in it or because 'SCF' is non-
207 zero), a negative value of 'SAF' will be treated as a zero
208 value; a value greater than zero may cause the entire label to
209 be written in the opposite direction along the curve if that
210 ensures that more characters of the label will be written at
211 angles between 'SAF'-90 and 'SAF'+90 degrees.
212 Generally, when 'SAF' is non-zero, it is either -360 or +360,
214 which has the effect of making the labels as nearly upright as
215 possible on the frame.
216 The value of 'SAF" must be in the range from -360 to +360.
218 The default value is 360.
220 'SBF' - Integer
222 String Buffering Flag: a flag that says whether output of labels
224 is to be buffered or not.
225 When 'SBF' is non-zero, buffering is done. This ensures that,
227 if the end of a curve occurs anywhere within a particular label,
228 no part of the label is written; instead, that part of the curve
229 is drawn using only the gap and solid elements of the dash
230 pattern. Buffering is also important when 'SCF' is non-zero or
231 there are "break" characters in a label string and 'SAF' is
232 greater than zero; in this case, the buffering makes it possible
233 to reorient the label as needed to make most of it upright.
234 When 'SBF' is zero, buffering is turned off. There may be gaps
236 at the ends of curves. If, in addition, 'SCF' is non-zero or
237 there are "break" characters in label strings, there may be
238 partial labels at the ends of curves.
239 The value of 'SBF' must be either 0 or 1.
241 The default value is 1.
243 'SCF' - Integer
245 Single Character Flag: When 'SCF' is non-zero, it says that the
247 label-string portions of character dash patterns are to be
248 broken into single-character pieces, each of which is to be
249 written by a separate call to PLCHHQ, PLCHMQ, or PLCHLQ.
250 If 'SCF' = 0, label strings are broken into pieces only at the
252 break points indicated by the use of "break" characters in the
253 strings.
254 It is not appropriate to use 'SCF' non-zero when PLCHHQ is being
256 used and a label string in the dash pattern contains function
257 codes that are meaningful to PLCHHQ; in that case, one should
258 leave 'SCF' = 0 and use the "break" character 'CRB' in the label
259 string to tell DASHPACK where it can be broken.
260 The value of 'SCF" must be either 0 or 1.
262 The default value is 0.
264 'SSL' - Real
266 Smoothed Segment Length: specifies how far apart the points used
268 to draw a smoothed curve should be.
269 The value of 'SSL' is given in the fractional coordinate system
271 and must be in the range from .000001 to 1.
272 The default value is .01.
274 'TCS' - Real
276 Tension on Cubic Splines: a value which, if negative, turns
278 smoothing off, and which, if non-negative, turns smoothing on
279 and, if greater than zero, specifies the desired tension to be
280 used on the cubic splines used to do the smoothing.
281 Note that only the routines DPCURV, DPFRST, DPVECT, DPLAST, and
283 DPSMTH are affected by the value of 'TCS'; the routines DPLINE
284 and DPDRAW never smooth. The routine DPSMTH always smooths: if
285 'TCS' is less than or equal to zero, simple cubic splines are
286 used, and, if 'TCS' is greater than zero, splines under tension
287 are used, in which case 'TCS' specifies the desired tension.
288 It's a bad idea to use values of 'TCS' much bigger than about
290 15, as this can cause overflows in the smoothing routines.
291 The default value is -1.
293 'WOC' - Real
295 Width Of Character: the character width to be used in writing
297 labels.
298 The value of 'WOC' is given in the fractional coordinate system
300 and must be in the range from .000001 to 1.
301 The default value is .01.
303 'WOG' - Real
305 Width of Gap: the width of each gap in the dashed line.
307 The value of 'WOG' is given in the fractional coordinate system
309 and must be in the range from .000001 to 1.
310 The default value is .005.
312 'WOS' - Real
314 Width of Solid: the width of each solid in the dashed line.
316 The value of 'WOS' is given in the fractional coordinate system
318 and must be in the range from .000001 to 1.
319 The default value is .005.
321
323 Online: dashpack, dpcurv, dpdraw, dpfrst, dpgetc, dpgeti, dpgetr,
324 dplast, dpline, dpsetc, dpseti, dpsetr, dpsmth, dpvect,
325 Hardcopy: None.
327
329 Copyright (C) 1987-2007
330 University Corporation for Atmospheric Research
331 This documentation is free software; you can redistribute it and/or
333 modify it under the terms of the GNU General Public License as
334 published by the Free Software Foundation; either version 2 of the
335 License, or (at your option) any later version.
336 This software is distributed in the hope that it will be useful, but
338 WITHOUT ANY WARRANTY; without even the implied warranty of
339 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
340 General Public License for more details.
341 You should have received a copy of the GNU General Public License along
343 with this software; if not, write to the Free Software Foundation,
344 Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
345UNIX March 1995 Dashpack_params(3NCARG)