Clever folds in a globe give new perspectives on Earth - tech - 10 December 2009 - New ... - 0 views
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fishead ...*∞º˙ on 01 Jan 10"Video: A new way to unfold the Earth's surface produces a new kind of map A new technique for unpeeling the Earth's skin and displaying it on a flat surface provides a fresh perspective on geography, making it possible to create maps that string out the continents for easy comparison, or lump together the world's oceans into one huge mass of water surrounded by coastlines. See a gallery of the new maps "Myriahedral projection" was developed by Jack van Wijk, a computer scientist at the Eindhoven University of Technology in the Netherlands. "The basic idea is surprisingly simple," says van Wijk. His algorithms divide the globe's surface into small polygons that are unfolded into a flat map, just as a cube can be unfolded into six squares. Cartographers have tried this trick before; van Wijk's innovation is to up the number of polygons from just a few to thousands. He has coined the word "myriahedral" to describe it, a combination of "myriad" with "polyhedron", the name for polygonal 3D shapes. Warping reality The mathematical impossibility of flattening the surface of a sphere has long troubled mapmakers. "Consider peeling an orange and trying to flatten it out," says van Wijk. "The surface has to distort or crack." Some solutions distort the size of the continents while roughly preserving their shape - the familiar Mercator projection, for instance, makes Europe and North America disproportionately large compared with Africa. Others, like the Peters projection, keep landmasses at the correct relative sizes, at the expense of warping their shapes. An ideal map would combine the best properties of both, but that is only possible by inserting gaps into the Earth's surface, resulting in a map with confusing interruptions. Van Wijk's method makes it possible to direct those cuts in a way that minimises such confusion. Maps of significance When generating a map he assigns a "weighting" to each edge on the polyhedron to signal its importance, influencing the pl
