3 94b5e3ff 2005-01-04 devnull map, mapdemo, mapd \- draw maps on various projections
4 058b0118 2005-01-03 devnull .SH SYNOPSIS
6 058b0118 2005-01-03 devnull .I projection
8 058b0118 2005-01-03 devnull .I option ...
11 058b0118 2005-01-03 devnull .B mapdemo
13 058b0118 2005-01-03 devnull .SH DESCRIPTION
15 058b0118 2005-01-03 devnull prepares on the standard output a
16 058b0118 2005-01-03 devnull map suitable for display by any
17 058b0118 2005-01-03 devnull plotting filter described in
18 058b0118 2005-01-03 devnull .IR plot (1).
19 058b0118 2005-01-03 devnull A menu of projections is produced in response to an unknown
20 058b0118 2005-01-03 devnull .IR projection .
21 058b0118 2005-01-03 devnull .I Mapdemo
22 058b0118 2005-01-03 devnull is a short course in mapping.
24 058b0118 2005-01-03 devnull The default data for
26 058b0118 2005-01-03 devnull are world shorelines.
29 058b0118 2005-01-03 devnull accesses more detailed data
30 058b0118 2005-01-03 devnull classified by feature.
32 058b0118 2005-01-03 devnull .BR -f " [ \fIfeature\fR ... ]"
33 058b0118 2005-01-03 devnull Features are ranked 1 (default) to 4 from major to minor.
34 058b0118 2005-01-03 devnull Higher-numbered ranks include all lower-numbered ones.
35 058b0118 2005-01-03 devnull Features are
37 058b0118 2005-01-03 devnull .TF country[1-3]
39 058b0118 2005-01-03 devnull .BR shore [ 1 - 4 ]
40 058b0118 2005-01-03 devnull seacoasts, lakes, and islands; option
42 058b0118 2005-01-03 devnull always shows
43 058b0118 2005-01-03 devnull .B shore1
45 058b0118 2005-01-03 devnull .BR ilake [ 1 - 2 ]
46 058b0118 2005-01-03 devnull intermittent lakes
48 058b0118 2005-01-03 devnull .BR river [ 1 - 4 ]
51 058b0118 2005-01-03 devnull .BR iriver [ 1 - 3 ]
52 058b0118 2005-01-03 devnull intermittent rivers
54 058b0118 2005-01-03 devnull .BR canal [ 1 - 3 ]
55 058b0118 2005-01-03 devnull .BR 3 =irrigation
58 058b0118 2005-01-03 devnull .BR glacier
60 058b0118 2005-01-03 devnull .BR iceshelf [ 12 ]
64 058b0118 2005-01-03 devnull .BR saltpan [ 12 ]
66 058b0118 2005-01-03 devnull .BR country [ 1 - 3 ]
67 058b0118 2005-01-03 devnull .BR 2 =disputed
68 058b0118 2005-01-03 devnull boundaries,
69 058b0118 2005-01-03 devnull .BR 3 =indefinite
70 058b0118 2005-01-03 devnull boundaries
72 058b0118 2005-01-03 devnull .BR state
73 058b0118 2005-01-03 devnull states and provinces (US and Canada only)
77 058b0118 2005-01-03 devnull In other options
78 058b0118 2005-01-03 devnull coordinates are in degrees, with north latitude
79 058b0118 2005-01-03 devnull and west longitude counted as positive.
81 058b0118 2005-01-03 devnull .BI -l " S N E W"
82 058b0118 2005-01-03 devnull Set the southern and northern latitude
83 058b0118 2005-01-03 devnull and the eastern and western longitude limits.
84 058b0118 2005-01-03 devnull Missing arguments are filled out from the list
85 058b0118 2005-01-03 devnull \-90, 90, \-180, 180,
86 058b0118 2005-01-03 devnull or lesser limits suitable to the
87 058b0118 2005-01-03 devnull projection at hand.
89 058b0118 2005-01-03 devnull .BI -k " S N E W
90 058b0118 2005-01-03 devnull Set the scale as if for a map with limits
92 058b0118 2005-01-03 devnull .I "S N E W"\f1.
93 058b0118 2005-01-03 devnull Do not consider any
97 058b0118 2005-01-03 devnull option in setting scale.
99 058b0118 2005-01-03 devnull .BI -o " lat lon rot"
100 058b0118 2005-01-03 devnull Orient the map in a nonstandard position.
101 058b0118 2005-01-03 devnull Imagine a transparent gridded sphere around the globe.
102 058b0118 2005-01-03 devnull Turn the overlay about the North Pole
103 058b0118 2005-01-03 devnull so that the Prime Meridian (longitude 0)
104 058b0118 2005-01-03 devnull of the overlay coincides with meridian
106 058b0118 2005-01-03 devnull on the globe.
107 058b0118 2005-01-03 devnull Then tilt the North Pole of the
108 058b0118 2005-01-03 devnull overlay along its Prime Meridian to latitude
110 058b0118 2005-01-03 devnull on the globe.
111 058b0118 2005-01-03 devnull Finally again turn the
112 058b0118 2005-01-03 devnull overlay about its `North Pole' so
113 058b0118 2005-01-03 devnull that its Prime Meridian coincides with the previous position
114 058b0118 2005-01-03 devnull of meridian
115 058b0118 2005-01-03 devnull .IR rot .
116 058b0118 2005-01-03 devnull Project the map in
117 058b0118 2005-01-03 devnull the standard form appropriate to the overlay, but presenting
118 058b0118 2005-01-03 devnull information from the underlying globe.
119 058b0118 2005-01-03 devnull Missing arguments are filled out from the list
120 058b0118 2005-01-03 devnull 90, 0, 0.
121 058b0118 2005-01-03 devnull In the absence of
122 058b0118 2005-01-03 devnull .BR - o ,
123 058b0118 2005-01-03 devnull the orientation is 90, 0,
127 058b0118 2005-01-03 devnull is the middle of the longitude range.
129 058b0118 2005-01-03 devnull .BI -w " S N E W"
130 058b0118 2005-01-03 devnull Window the map by the specified latitudes
131 058b0118 2005-01-03 devnull and longitudes in the tilted, rotated coordinate system.
132 058b0118 2005-01-03 devnull Missing arguments are filled out from the list \-90, 90, \-180, 180.
133 058b0118 2005-01-03 devnull (It is wise to give an encompassing
135 058b0118 2005-01-03 devnull option with
136 058b0118 2005-01-03 devnull .BR -w .
137 058b0118 2005-01-03 devnull Otherwise for small windows computing time
138 058b0118 2005-01-03 devnull varies inversely with area!)
140 058b0118 2005-01-03 devnull .BI -d " n"
141 058b0118 2005-01-03 devnull For speed, plot only every
142 058b0118 2005-01-03 devnull .IR n th
146 058b0118 2005-01-03 devnull Reverse left and right
147 058b0118 2005-01-03 devnull (good for star charts and inside-out views).
152 058b0118 2005-01-03 devnull Switch to a normally suppressed sheet of the map, such as the
153 058b0118 2005-01-03 devnull back side of the earth in orthographic projection.
160 058b0118 2005-01-03 devnull Superpose; outputs for a
162 058b0118 2005-01-03 devnull map (no closing) and a
164 058b0118 2005-01-03 devnull map (no opening) may be concatenated.
166 058b0118 2005-01-03 devnull .BI -g " dlat dlon res"
167 058b0118 2005-01-03 devnull Grid spacings are
168 058b0118 2005-01-03 devnull .IR dlat ,
169 058b0118 2005-01-03 devnull .IR dlon .
170 058b0118 2005-01-03 devnull Zero spacing means no grid.
173 058b0118 2005-01-03 devnull is taken to be zero.
176 058b0118 2005-01-03 devnull is taken the same as
177 058b0118 2005-01-03 devnull .IR dlat .
178 058b0118 2005-01-03 devnull Grid lines are drawn to a resolution of
180 058b0118 2005-01-03 devnull (2° or less by default).
181 058b0118 2005-01-03 devnull In the absence of
182 058b0118 2005-01-03 devnull .BR - g ,
183 058b0118 2005-01-03 devnull grid spacing is 10°.
185 058b0118 2005-01-03 devnull .BI -p " lat lon extent"
186 058b0118 2005-01-03 devnull Position the point
187 058b0118 2005-01-03 devnull .I lat, lon
188 058b0118 2005-01-03 devnull at the center of the plotting area.
189 058b0118 2005-01-03 devnull Scale the map so that the height (and width) of the
190 058b0118 2005-01-03 devnull nominal plotting area is
191 058b0118 2005-01-03 devnull .I extent
192 058b0118 2005-01-03 devnull times the size of one degree of latitude
193 058b0118 2005-01-03 devnull at the center.
194 058b0118 2005-01-03 devnull By default maps are scaled and positioned
195 058b0118 2005-01-03 devnull to fit within the plotting area.
197 058b0118 2005-01-03 devnull .I extent
198 058b0118 2005-01-03 devnull overrides option
199 058b0118 2005-01-03 devnull .BR -k .
201 058b0118 2005-01-03 devnull .BI -c " x y rot"
202 058b0118 2005-01-03 devnull After all other positioning and scaling operations
203 058b0118 2005-01-03 devnull have been performed, rotate the image
205 058b0118 2005-01-03 devnull degrees counterclockwise about the center
206 058b0118 2005-01-03 devnull and move the center to position
209 058b0118 2005-01-03 devnull where the nominal plotting area is
210 058b0118 2005-01-03 devnull .RI \-1≤ x ≤1,
211 058b0118 2005-01-03 devnull .RI \-1≤ y ≤1.
212 058b0118 2005-01-03 devnull Missing arguments are taken to be 0.
214 058b0118 2005-01-03 devnull Allow the map to extend outside the nominal plotting area.
216 058b0118 2005-01-03 devnull .BR -m " [ \fIfile\fP ... ]"
218 058b0118 2005-01-03 devnull map data from named files.
219 058b0118 2005-01-03 devnull If no files are named, omit map data.
220 058b0118 2005-01-03 devnull Names that do not exist as pathnames are looked up in
221 058b0118 2005-01-03 devnull a standard directory, which contains, in addition to the
222 058b0118 2005-01-03 devnull data for
223 058b0118 2005-01-03 devnull .BR -f ,
226 058b0118 2005-01-03 devnull .TF counties
228 058b0118 2005-01-03 devnull .B world
229 058b0118 2005-01-03 devnull World Data Bank I (default)
231 058b0118 2005-01-03 devnull .B states
232 058b0118 2005-01-03 devnull US map from Census Bureau
234 058b0118 2005-01-03 devnull .B counties
235 058b0118 2005-01-03 devnull US map from Census Bureau
239 058b0118 2005-01-03 devnull The environment variables
242 058b0118 2005-01-03 devnull .B MAPDIR
243 058b0118 2005-01-03 devnull change the default
244 058b0118 2005-01-03 devnull map and default directory.
246 058b0118 2005-01-03 devnull .BI -b " \fR[\fPlat0 lon0 lat1 lon1\fR... ]"
247 058b0118 2005-01-03 devnull Suppress the drawing of the normal boundary
248 058b0118 2005-01-03 devnull (defined by options
251 058b0118 2005-01-03 devnull .BR -w ).
252 058b0118 2005-01-03 devnull Coordinates, if present, define the vertices of a
253 058b0118 2005-01-03 devnull polygon to which the map is clipped.
254 058b0118 2005-01-03 devnull If only two vertices are given, they are taken to be the
255 058b0118 2005-01-03 devnull diagonal of a rectangle.
256 058b0118 2005-01-03 devnull To draw the polygon, give its vertices as a
260 058b0118 2005-01-03 devnull .BI -t " file ..."
262 058b0118 2005-01-03 devnull .I files
263 058b0118 2005-01-03 devnull contain lists of points,
264 058b0118 2005-01-03 devnull given as latitude-longitude pairs in degrees.
265 058b0118 2005-01-03 devnull If the first file is named
267 058b0118 2005-01-03 devnull the standard input is taken instead.
268 058b0118 2005-01-03 devnull The points of each list are plotted as connected `tracks'.
270 058b0118 2005-01-03 devnull Points in a track file may be followed by label strings.
271 058b0118 2005-01-03 devnull A label breaks the track.
272 058b0118 2005-01-03 devnull A label may be prefixed by
273 058b0118 2005-01-03 devnull \fL"\fR,
277 058b0118 2005-01-03 devnull and is terminated by a newline.
278 058b0118 2005-01-03 devnull An unprefixed string or a string prefixed with
281 058b0118 2005-01-03 devnull is displayed at the designated point.
282 058b0118 2005-01-03 devnull The first word of a
286 058b0118 2005-01-03 devnull string names a special symbol (see option
287 058b0118 2005-01-03 devnull .BR -y ).
288 058b0118 2005-01-03 devnull An optional numerical second word is a scale factor
289 058b0118 2005-01-03 devnull for the size of the symbol, 1 by default.
292 058b0118 2005-01-03 devnull symbol is aligned with its top to the north; a
294 058b0118 2005-01-03 devnull symbol is aligned vertically on the page.
296 058b0118 2005-01-03 devnull .BI -u " file ..."
298 058b0118 2005-01-03 devnull .BR -t ,
299 058b0118 2005-01-03 devnull except the tracks are
300 058b0118 2005-01-03 devnull unbroken lines.
301 058b0118 2005-01-03 devnull .RB ( -t
302 058b0118 2005-01-03 devnull tracks appear as dot-dashed lines if the plotting filter supports them.)
304 058b0118 2005-01-03 devnull .BI -y " file
307 058b0118 2005-01-03 devnull contains
308 d32deab1 2020-08-16 rsc .MR plot (7) -style
309 058b0118 2005-01-03 devnull data for
313 058b0118 2005-01-03 devnull labels in
318 058b0118 2005-01-03 devnull Each symbol is defined by a comment
319 058b0118 2005-01-03 devnull .BI : name
320 058b0118 2005-01-03 devnull then a sequence of
324 058b0118 2005-01-03 devnull commands.
325 058b0118 2005-01-03 devnull Coordinates (0,0) fall on the plotting point.
326 058b0118 2005-01-03 devnull Default scaling is as if the nominal plotting range were
327 058b0118 2005-01-03 devnull .LR "ra -1 -1 1 1" ;
329 058b0118 2005-01-03 devnull commands in
331 058b0118 2005-01-03 devnull change the scaling.
332 058b0118 2005-01-03 devnull .SS Projections
333 058b0118 2005-01-03 devnull Equatorial projections centered on the Prime Meridian
334 058b0118 2005-01-03 devnull (longitude 0).
335 058b0118 2005-01-03 devnull Parallels are straight horizontal lines.
338 058b0118 2005-01-03 devnull .TP 1.5i
339 058b0118 2005-01-03 devnull .B mercator
340 058b0118 2005-01-03 devnull equally spaced straight meridians, conformal,
341 058b0118 2005-01-03 devnull straight compass courses
343 058b0118 2005-01-03 devnull .B sinusoidal
344 058b0118 2005-01-03 devnull equally spaced parallels,
345 058b0118 2005-01-03 devnull equal-area, same as
346 058b0118 2005-01-03 devnull .LR "bonne 0" .
348 058b0118 2005-01-03 devnull .BI cylequalarea " lat0"
349 058b0118 2005-01-03 devnull equally spaced straight meridians, equal-area,
350 058b0118 2005-01-03 devnull true scale on
353 058b0118 2005-01-03 devnull .B cylindrical
354 058b0118 2005-01-03 devnull central projection on tangent cylinder
356 058b0118 2005-01-03 devnull .BI rectangular " lat0"
357 058b0118 2005-01-03 devnull equally spaced parallels, equally spaced straight meridians, true scale on
360 058b0118 2005-01-03 devnull .BI gall " lat0"
361 058b0118 2005-01-03 devnull parallels spaced stereographically on prime meridian, equally spaced straight
362 058b0118 2005-01-03 devnull meridians, true scale on
365 058b0118 2005-01-03 devnull .B mollweide
366 058b0118 2005-01-03 devnull (homalographic) equal-area, hemisphere is a circle
368 058b0118 2005-01-03 devnull .B gilbert()
369 058b0118 2005-01-03 devnull sphere conformally mapped on hemisphere and viewed orthographically
371 058b0118 2005-01-03 devnull .B gilbert
372 058b0118 2005-01-03 devnull globe mapped conformally on hemisphere, viewed orthographically
375 058b0118 2005-01-03 devnull Azimuthal projections centered on the North Pole.
376 058b0118 2005-01-03 devnull Parallels are concentric circles.
377 058b0118 2005-01-03 devnull Meridians are equally spaced radial lines.
380 058b0118 2005-01-03 devnull .TP 1.5i
381 058b0118 2005-01-03 devnull .B azequidistant
382 058b0118 2005-01-03 devnull equally spaced parallels,
383 058b0118 2005-01-03 devnull true distances from pole
385 058b0118 2005-01-03 devnull .B azequalarea
386 058b0118 2005-01-03 devnull equal-area
388 058b0118 2005-01-03 devnull .B gnomonic
389 058b0118 2005-01-03 devnull central projection on tangent plane,
390 058b0118 2005-01-03 devnull straight great circles
392 058b0118 2005-01-03 devnull .BI perspective " dist"
393 058b0118 2005-01-03 devnull viewed along earth's axis
395 058b0118 2005-01-03 devnull earth radii from center of earth
397 058b0118 2005-01-03 devnull .B orthographic
398 058b0118 2005-01-03 devnull viewed from infinity
400 058b0118 2005-01-03 devnull .B stereographic
401 058b0118 2005-01-03 devnull conformal, projected from opposite pole
404 058b0118 2005-01-03 devnull .IR radius " = tan(2\(mu" colatitude ),
405 058b0118 2005-01-03 devnull used in X-ray crystallography
407 058b0118 2005-01-03 devnull .BI fisheye " n"
408 058b0118 2005-01-03 devnull stereographic seen from just inside medium with refractive index
411 058b0118 2005-01-03 devnull .BI newyorker " r"
412 058b0118 2005-01-03 devnull .IR radius " = log(" colatitude / r ):
413 058b0118 2005-01-03 devnull .I New Yorker
414 058b0118 2005-01-03 devnull map from viewing pedestal of radius
419 058b0118 2005-01-03 devnull Polar conic projections symmetric about the Prime Meridian.
420 058b0118 2005-01-03 devnull Parallels are segments of concentric circles.
421 058b0118 2005-01-03 devnull Except in the Bonne projection,
422 058b0118 2005-01-03 devnull meridians are equally spaced radial
423 058b0118 2005-01-03 devnull lines orthogonal to the parallels.
426 058b0118 2005-01-03 devnull .TP 1.5i
427 058b0118 2005-01-03 devnull .BI conic " lat0"
428 058b0118 2005-01-03 devnull central projection on cone tangent at
431 058b0118 2005-01-03 devnull .BI simpleconic " lat0 lat1"
432 058b0118 2005-01-03 devnull equally spaced parallels, true scale on
437 058b0118 2005-01-03 devnull .BI lambert " lat0 lat1"
438 058b0118 2005-01-03 devnull conformal, true scale on
443 058b0118 2005-01-03 devnull .BI albers " lat0 lat1"
444 058b0118 2005-01-03 devnull equal-area, true scale on
449 058b0118 2005-01-03 devnull .BI bonne " lat0"
450 058b0118 2005-01-03 devnull equally spaced parallels, equal-area,
451 058b0118 2005-01-03 devnull parallel
453 058b0118 2005-01-03 devnull developed from tangent cone
456 058b0118 2005-01-03 devnull Projections with bilateral symmetry about
457 058b0118 2005-01-03 devnull the Prime Meridian
458 058b0118 2005-01-03 devnull and the equator.
461 058b0118 2005-01-03 devnull .TP 1.5i
462 058b0118 2005-01-03 devnull .B polyconic
463 058b0118 2005-01-03 devnull parallels developed from tangent cones,
464 058b0118 2005-01-03 devnull equally spaced along Prime Meridian
466 058b0118 2005-01-03 devnull .B aitoff
467 058b0118 2005-01-03 devnull equal-area projection of globe onto 2-to-1
468 058b0118 2005-01-03 devnull ellipse, based on
469 058b0118 2005-01-03 devnull .I azequalarea
471 058b0118 2005-01-03 devnull .B lagrange
472 058b0118 2005-01-03 devnull conformal, maps whole sphere into a circle
474 058b0118 2005-01-03 devnull .BI bicentric " lon0"
475 058b0118 2005-01-03 devnull points plotted at true azimuth from two
476 058b0118 2005-01-03 devnull centers on the equator at longitudes
477 058b0118 2005-01-03 devnull .IR ±lon0 ,
478 058b0118 2005-01-03 devnull great circles are straight lines
479 058b0118 2005-01-03 devnull (a stretched
480 058b0118 2005-01-03 devnull .IR gnomonic
483 058b0118 2005-01-03 devnull .BI elliptic " lon0"
484 058b0118 2005-01-03 devnull points plotted at true distance from
485 058b0118 2005-01-03 devnull two centers on the equator at longitudes
486 058b0118 2005-01-03 devnull .I ±lon0
488 058b0118 2005-01-03 devnull .B globular
489 058b0118 2005-01-03 devnull hemisphere is circle,
490 058b0118 2005-01-03 devnull circular arc meridians equally spaced on equator,
491 058b0118 2005-01-03 devnull circular arc parallels equally spaced on 0- and 90-degree meridians
493 058b0118 2005-01-03 devnull .B vandergrinten
494 058b0118 2005-01-03 devnull sphere is circle,
495 058b0118 2005-01-03 devnull meridians as in
496 058b0118 2005-01-03 devnull .IR globular ,
497 058b0118 2005-01-03 devnull circular arc parallels resemble
498 058b0118 2005-01-03 devnull .I mercator
501 058b0118 2005-01-03 devnull Doubly periodic conformal projections.
503 058b0118 2005-01-03 devnull .TP 1.5i
504 058b0118 2005-01-03 devnull .B guyou
505 058b0118 2005-01-03 devnull W and E hemispheres are square
508 058b0118 2005-01-03 devnull .B square
509 058b0118 2005-01-03 devnull world is square with Poles
510 058b0118 2005-01-03 devnull at diagonally opposite corners
512 058b0118 2005-01-03 devnull .B tetra
513 058b0118 2005-01-03 devnull map on tetrahedron with edge
514 058b0118 2005-01-03 devnull tangent to Prime Meridian at S Pole,
515 058b0118 2005-01-03 devnull unfolded into equilateral triangle
518 058b0118 2005-01-03 devnull world is hexagon centered
519 058b0118 2005-01-03 devnull on N Pole, N and S hemispheres are equilateral
520 058b0118 2005-01-03 devnull triangles
523 058b0118 2005-01-03 devnull Miscellaneous projections.
526 058b0118 2005-01-03 devnull .TP 1.5i
527 058b0118 2005-01-03 devnull .BI harrison " dist angle"
528 058b0118 2005-01-03 devnull oblique perspective from above the North Pole,
530 058b0118 2005-01-03 devnull earth radii from center of earth, looking
531 058b0118 2005-01-03 devnull along the Date Line
532 058b0118 2005-01-03 devnull .I angle
533 058b0118 2005-01-03 devnull degrees off vertical
535 058b0118 2005-01-03 devnull .BI trapezoidal " lat0 lat1"
536 058b0118 2005-01-03 devnull equally spaced parallels,
537 058b0118 2005-01-03 devnull straight meridians equally spaced along parallels,
538 058b0118 2005-01-03 devnull true scale at
542 058b0118 2005-01-03 devnull on Prime Meridian
545 058b0118 2005-01-03 devnull .B lune(lat,angle)
546 058b0118 2005-01-03 devnull conformal, polar cap above latitude
548 058b0118 2005-01-03 devnull maps to convex lune with given
549 058b0118 2005-01-03 devnull .I angle
550 058b0118 2005-01-03 devnull at 90\(deE and 90\(deW
552 058b0118 2005-01-03 devnull Retroazimuthal projections.
553 058b0118 2005-01-03 devnull At every point the angle between vertical and a straight line to
554 058b0118 2005-01-03 devnull `Mecca', latitude
556 058b0118 2005-01-03 devnull on the prime meridian,
557 058b0118 2005-01-03 devnull is the true bearing of Mecca.
560 058b0118 2005-01-03 devnull .TP 1.5i
561 058b0118 2005-01-03 devnull .BI mecca " lat0"
562 058b0118 2005-01-03 devnull equally spaced vertical meridians
564 058b0118 2005-01-03 devnull .BI homing " lat0"
565 058b0118 2005-01-03 devnull distances to Mecca are true
568 058b0118 2005-01-03 devnull Maps based on the spheroid.
569 058b0118 2005-01-03 devnull Of geodetic quality, these projections do not make sense
570 058b0118 2005-01-03 devnull for tilted orientations.
571 058b0118 2005-01-03 devnull For descriptions, see corresponding maps above.
574 058b0118 2005-01-03 devnull .TP 1.5i
575 058b0118 2005-01-03 devnull .B sp_mercator
577 058b0118 2005-01-03 devnull .BI sp_albers " lat0 lat1"
578 058b0118 2005-01-03 devnull .SH EXAMPLES
581 058b0118 2005-01-03 devnull map perspective 1.025 -o 40.75 74
582 058b0118 2005-01-03 devnull A view looking down on New York from 100 miles
583 058b0118 2005-01-03 devnull (0.025 of the 4000-mile earth radius) up.
584 058b0118 2005-01-03 devnull The job can be done faster by limiting the map so as not to `plot'
585 058b0118 2005-01-03 devnull the invisible part of the world:
586 058b0118 2005-01-03 devnull .LR "map perspective 1.025 -o 40.75 74 -l 20 60 30 100".
587 058b0118 2005-01-03 devnull A circular border can be forced by adding option
588 058b0118 2005-01-03 devnull .LR "-w 77.33" .
589 058b0118 2005-01-03 devnull (Latitude 77.33° falls just inside a polar cap of
590 058b0118 2005-01-03 devnull opening angle arccos(1/1.025) = 12.6804°.)
593 058b0118 2005-01-03 devnull map mercator -o 49.25 -106 180
594 058b0118 2005-01-03 devnull An `equatorial' map of the earth
595 058b0118 2005-01-03 devnull centered on New York.
596 058b0118 2005-01-03 devnull The pole of the map is placed 90\(de away (40.75+49.25=90)
598 058b0118 2005-01-03 devnull other side of the earth.
599 058b0118 2005-01-03 devnull A 180° twist around the pole of the map arranges that the
600 058b0118 2005-01-03 devnull `Prime Meridian' of the map runs from the pole of the
601 058b0118 2005-01-03 devnull map over the North Pole to New York
602 058b0118 2005-01-03 devnull instead of down the back side of the earth.
603 058b0118 2005-01-03 devnull The same effect can be had from
605 058b0118 2005-01-03 devnull map mercator -o 130.75 74
608 058b0118 2005-01-03 devnull map albers 28 45 -l 20 50 60 130 -m states
609 058b0118 2005-01-03 devnull A customary curved-latitude map of the United States.
612 058b0118 2005-01-03 devnull map harrison 2 30 -l -90 90 120 240 -o 90 0 0
613 058b0118 2005-01-03 devnull A fan view covering 60° on either
614 058b0118 2005-01-03 devnull side of the Date Line, as seen from one earth radius
615 058b0118 2005-01-03 devnull above the North Pole gazing at the
616 058b0118 2005-01-03 devnull earth's limb, which is 30° off vertical.
619 058b0118 2005-01-03 devnull option overrides the default
620 058b0118 2005-01-03 devnull .BR "-o 90 0 180" ,
621 058b0118 2005-01-03 devnull which would rotate
622 058b0118 2005-01-03 devnull the scene to behind the observer.
623 058b0118 2005-01-03 devnull .SH FILES
624 058b0118 2005-01-03 devnull .TF /lib/map/[1-4]??
626 058b0118 2005-01-03 devnull .B /lib/map/[1-4]??
627 058b0118 2005-01-03 devnull World Data Bank II, for
630 058b0118 2005-01-03 devnull .B /lib/map/*
631 058b0118 2005-01-03 devnull maps for
634 058b0118 2005-01-03 devnull .B /lib/map/*.x
635 058b0118 2005-01-03 devnull map indexes
638 058b0118 2005-01-03 devnull Map driver program
639 058b0118 2005-01-03 devnull .SH SOURCE
640 c3674de4 2005-01-11 devnull .B \*9/src/cmd/map
641 058b0118 2005-01-03 devnull .SH "SEE ALSO"
642 058b0118 2005-01-03 devnull .IR map (7),
643 d32deab1 2020-08-16 rsc .MR plot (1)
644 058b0118 2005-01-03 devnull .SH DIAGNOSTICS
645 058b0118 2005-01-03 devnull `Map seems to be empty'\(ema coarse survey found
646 058b0118 2005-01-03 devnull zero extent within the
650 058b0118 2005-01-03 devnull bounds; for maps of limited extent
651 058b0118 2005-01-03 devnull the grid resolution,
652 058b0118 2005-01-03 devnull .IR res ,
653 058b0118 2005-01-03 devnull or the limits may have to be refined.
654 058b0118 2005-01-03 devnull .SH BUGS
655 058b0118 2005-01-03 devnull Windows (option
656 058b0118 2005-01-03 devnull .BR -w )
657 058b0118 2005-01-03 devnull cannot cross the Date Line.
658 058b0118 2005-01-03 devnull No borders appear along edges arising from
659 058b0118 2005-01-03 devnull visibility limits.
660 058b0118 2005-01-03 devnull Segments that cross a border are dropped, not clipped.
661 058b0118 2005-01-03 devnull Excessively large scale or
663 058b0118 2005-01-03 devnull setting may cause long line segments to be dropped.
665 058b0118 2005-01-03 devnull tries to draw grid lines dotted and
667 058b0118 2005-01-03 devnull tracks dot-dashed.
668 058b0118 2005-01-03 devnull As very few plotting filters properly support
669 058b0118 2005-01-03 devnull curved textured lines, these lines are likely to
670 058b0118 2005-01-03 devnull appear solid.
671 058b0118 2005-01-03 devnull The west-longitude-positive convention
672 058b0118 2005-01-03 devnull betrays Yankee chauvinism.
673 058b0118 2005-01-03 devnull .I Gilbert
674 058b0118 2005-01-03 devnull should be a map from sphere to sphere, independent of
675 058b0118 2005-01-03 devnull the mapping from sphere to plane.
