Mapping Hacks

130

|

Chapter 3, Mapping Your World

#28 Experiment with Different Cartographic Projections

HACK

three-dimensional figure. We discuss how to make use of Fuller’s projection

in “Plot Dymaxion Maps in Perl”

[Hack #31].

Conic Projections

Yet a third type of projection can be constructed by projecting a globe onto

the surface of a cone placed over the top of it. If cylindrical projections are

traditionally used to map equatorial regions with a minimum of distortion,

and azimuthal projections to map polar regions similarly, then conic projec-

tions are traditionally used to map the middle latitudes most effectively.

Lambert’s Conformal Conic projection. With the following command, we can

use Lambert’s Conformal Conic projection to make a quite reasonable map

of Europe, as shown in Figure 3-24:

$ pscoast -JL15/50/40/65/18c -R-12/50/34/72 -G64/255/128 -S64/128/255 -N1 \

-A5000 > europe.ps

Figure 3-22. The world shown relative to distance and direction from Sydney

Experiment with Different Cartographic Projections #28

Chapter 3, Mapping Your World

|

131

HACK

pscoast takes five arguments for its -JL option, which generates a Lambert’s

Conformal Conic projection. The first two are the longitude and latitude of

the center of the projection, the next two are the two standard parallels of

the projection—i.e., the lines ...