Provided by: libncarg-dev_6.4.0-9_amd64 
NAME
Dashline_params - Brief descriptions of all internal parameters of Dashline.
DESCRIPTION
No parameter-access routines are available for the utility Dashline. Parameters are set
through the common blocks SMFLAG, INTPR, and DASHD1.
There are four different versions of Dashline: normal, quick, smooth, and super. Which
version is used depends on options used on the ncargf77 command line. The lines drawn by
the different versions can vary considerably in appearance.
The following set of common blocks may be used to access any of the internal parameters of
the Dashline utility:
COMMON /SMFLAG/ IOFFS
COMMON /INTPR / IPAU,FPART,TENSN,NP,SMALL,L1,ADDLR,ADDTB,MLLINE,
+ ICLOSE
COMMON /DASHD1/ ISL,L,ISIZE,IP(100),NWDSM1,IPFLAG(100),MNCSTR,IGP
The following table indicates which of the internal parameters affect the behavior of the
various versions of Dashline ("Y" indicates an effect, "N" indicates no effect):
Parameter QUICK NORMAL SMOOTH SUPER
--------- ----- ------ ------ -----
ADDLR N N N Y
ADDTB N N N Y
FPART N Y Y Y
ICLOSE Y Y Y Y
IGP N Y Y Y
IOFFS N N Y Y
IPAU Y Y Y Y
L1 N N Y Y
MLLINE N N N Y
NP N N Y Y
SMALL N N Y Y
TENSN N N Y Y
PARAMETER DESCRIPTIONS
ADDLR The amount of free space to be left on the left and on the right of each
character string, stated as the desired number of NDCs (Normalized Device
Coordinates) times 1023. This only affects the "super" version of Dashline;
it changes the size of the area marked around a label in the bit map that is
used for culling crowded lines. [Default = 2. (2./1023. NDCs)]
ADDTB The amount of free space to be left on the top and on the bottom of each
character string, stated as the desired number of NDCs (Normalized Device
Coordinates) times 1023. This only affects the "super" version of Dashline;
it changes the size of the area marked around a label in the bit map that is
used for culling crowded lines. [Default = 2. (2./1023. NDCs)]
FPART A multiplication factor for the length of the first solid line segment on any
curve. This can be used to offset labels. For example, if FPART = .5, the
first solid line segment is only one-half as long as the other solid line
segments. This will move all labels on the current curve towards the
beginning of the curve and thereby reduce the probability of a label being
written on top of a label on a nearby curve drawn with FPART = 1. [Default =
1.]
ICLOSE An internal or external call to move the "drawing pen" (pen-up) to a specific
position is executed only if the position is more than ICLOSE units away from
the current pen position (the distance is measured as the absolute difference
in X-coordinates plus the absolute difference in Y-coordinates). The unit of
measurement is 32767 integer units in each of the X and Y dimensions.
[Default = 6]
IGP Flag to control whether gaps are left for labels along a curve. If no gaps
are left, the labels don't look as good, but you can be sure of what the curve
is doing in the regions occupied by the labels.
9 A gap is left.
0 No gap is left.
[Default = 9]
IOFFS Flag used to turn smoothing off.
0 Smoothing.
1 No smoothing.
[Default = 0]
IPAU The length of the gap or solid line associated with each element of a dash
pattern defined by a call to DASHDB, given as the desired value in NDCs
(Normalized Device Coordinates) times 1023. Such a dash pattern is repeated
approximately every REAL(IPAU)/64. NDC units along the length of a curve.
[Default = 3 (3./1023. NDCs)]
L1 The maximum number of points to be saved at one time. If there are more than
L1 points on a given line, L1 points are processed, then the next L1, and so
on, until the entire line is processed. Smoothness between segments is
maintained automatically. If L1 is increased, the dimensions of XSAVE, YSAVE,
XP, YP, TEMP, and SLEN in the routine FDVDLD must be increased to the new
value of L1. [Default = 70]
MLLINE The maximum length in either coordinate of a single line segment to be
processed by the crowded line algorithm. Line segments longer than MLLINE
units in either coordinate are broken into smaller segments, each of which is
processed separately. This is done to prevent anomalies in the removal of
long line segments, since only the starting point and end point of each line
segment is checked in that process. The unit of measurement is 32767 integer
units in each of the X and Y dimensions. [Default = 384]
NP Determines how many points are used to draw each smoothed curve. The value of
NP is twice the maximum number of interpolated points on a horizontal curve
with length equal to that of the width of the grid. More points per unit
length are interpolated for short lines than for long lines. [Default = 150]
SMALL When the points on a line are being processed, only the first of two
consecutive points is saved if the points are less than SMALL units apart.
This procedure is to prevent cusps. The unit of measurement is 32767 integer
units in each of the X and Y dimensions. [Default = 128.]
TENSN Tension factor. Must be greater than 0. A large tension factor (30.) would
essentially turn off smoothing. [Default = 2.5]
SEE ALSO
Online: dashline, curved, dashdb, dashdc, frstd, lastd, lined, reset, vectd, ncarg_cbind
Hardcopy: NCAR Graphics Contouring and Mapping Tutorial; NCAR Graphics Fundamentals, UNIX
Version; User's Guide for NCAR GKS-0A Graphics
COPYRIGHT
Copyright (C) 1987-2009
University Corporation for Atmospheric Research
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