Mapping Hacks

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Chapter 3, Mapping Your World

#34 Map Other Planets

HACK

<image width="629" height="768" xlink:href="suomenlinna-1024.jpg" />

</g>

<!-- nifca -->

<circle cy="6014319" cx="2498291" r="10" fill="red" />

<!-- submarine -->

<circle cy="6014238" cx="2498956" r="10" fill="red" />

<!-- labour camp -->

<circle cy="6014484" cx="2499052" r="10" fill="red" />

<!-- ferry -->

<circle cy="6014910" cx="2498424" r="10" fill="red" />

The content of the transform parameter, you’ll notice, is a matrix transform

in exactly the form as the one in the world file! Now you can plot points in

their original geographic coordinates directly onto this map. Unfortunately,

the transformation process can produce a lossy effect in the SVG viewer, and

the map can look jagged, blurry, or warped—especially at extreme lati-

tudes, if you’re using unprojected coordinates. The other downside is that

SVG viewers typically only display points with integer accuracy, so you have

to multiply latitude and longitude by 100,000 to scale them up to some-

thing viewable.

Another approach to the same problem might be to transform the geometry

of the points and leave the map alone. We can do this by taking the inverse

of the original affine matrix, and applying it to the points, instead of the

base map.

HACK

#34

Map Other Planets Hack #34

Explore the celestial spheres (and spheroids) with standard GIS tools.

The universe is a big place, perhaps the biggest. ...