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The new point plotting format (reposted)
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Author:  Tim Vasquez [ Mon Mar 02, 2009 5:07 pm ]
Post subject:  The new point plotting format (reposted)

(I had to delete the post about v1.40d being released since it's outdated, but this information about point plotting needed to be saved. Here it is. - Tim)

Digital Atmosphere Equinox v1.40d and later versions add some code to handle the Map > Add Overlay >
Points algorithms.

A version called v1.40c was online for a few hours; if you
happened to obtain it, please replace it with v1.40d.

Please ignore the Plotting Format message sent Monday night (in another thread);
there have been drastic and very significant revisions (see below).
Also note that Digital Atmosphere v1.40d will plot the older
PLS format; see below for more information.

Point Plotting Format
Prepared: 25 November 2008 (significantly amended)

Effective with Equinox V1.40d, we are now using a highly flexible
format for plotting user-defined points rather than the rigid
version used in earlier versions of Digital Atmosphere.

The file must be stored with the extension "plt", for example
mypoints.plt and must be in a standard plain text file (so use
Notepad when possible). Digital Atmosphere will import the
older "pls" format, and if your File > Preferences > Maps >
Copy Viewed Point Files From PLS to PLT Format option
is checked, Digital Atmosphere will make a converted "PLT"
version of the selected file in the new format which can
be edited and used.

In a PLT file, each row is made up of several words, separated
by spaces or tabs, which must be in this format:

Full version:
type lat long text #rrggbb *width @shape :optionalcomments

Simplest version:
type lat long

type = Element type (+ or .)[INDENT] + = A single point to be plotted
. = A line drawn from coordinate of preceding row to current row
[/INDENT]lat = An expression of latitude (see below)
long = An expression of longitude (see below)
text = Optional text identifying the point. Prefix with
a period to prevent the label from plotting.
#rrggbb = Optional color in 6-digit hex code (e.g. #FFFFFF is white)[INDENT] rr = Hexadecimal red value (00 to FF)
gg = Hexadecimal green value (00 to FF)
bb = Hexadecimal blue value (00 to FF)
[/INDENT]*width = Optional pen line width (1, 2, or 3, e.g. *2)
@shape = Optional point marker type (e.g. @24)[INDENT] 11 = Circle, unfilled, 1 pixel in diameter
12 = Circle, unfilled, 2 pixels in diameter
13 = Circle, unfilled, 3 pixels in diameter
14 = Circle, unfilled, 4 pixels in diameter
21 = Circle, filled, 1 pixel in diameter
22 = Circle, filled, 2 pixels in diameter
23 = Circle, filled, 3 pixels in diameter
24 = Circle, filled, 4 pixels in diameter
31 = Square, unfilled, 1 pixel in diameter
32 = Square, unfilled, 2 pixels in diameter
33 = Square, unfilled, 3 pixels in diameter
34 = Square, unfilled, 4 pixels in diameter
41 = Square, filled, 1 pixel in diameter
42 = Square, filled, 2 pixels in diameter
43 = Square, filled, 3 pixels in diameter
44 = Square, filled, 4 pixels in diameter[/INDENT]Latitude and longitude formats are interpreted to give users
maximum flexibility, and may be expressed as follows (where s
is a mathematical sign or h is hemisphere N, S, E, or W):

sD.DDDD Decimal degrees to any number of places (i.e. -37.5939)
hDDMM Degrees and arcminutes (i.e. N3603)
DDMMh Degrees and arcminutes (i.e. 3603N)
hDDMMSS Degrees, arcminutes, arcseconds (i.e. N360338)
DDMMSSh Degrees, arcminutes, arcseconds (i.e. 360338N)

DD, MM, and SS, when used for expressing degrees, arcminutes,
and arcseconds, MUST be in two digits with a leading zero if
needed, unless expressing degrees of longitude in which case
three digits is permitted (i.e. N4411 W09733).

To encode 44 deg 1 minute north:
WRONG: 441
RIGHT: N4401

All text on a row starting at a colon (:) will be treated as a
comment, so start a row with a colon to make an entire row
a comment, or add it to the end of a row to add comments to
a row containing data.

This scheme is a little more complicated but it will give users maximum
flexibility for plotting out all kinds of ad hoc geographic work and
without having to create an ugly shapefile.

+ 321531N 932456W .Boundary
. 313232N 912421W
. 311123N 914210W .End
+ 242342N 805311W Airfield1 #FFAAFF *2 @14
+ 292356N 985344W Joe : This is joe's house

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