Talk:Dymaxion map

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Peters Projection

Is Dymaxion Map the same as the Peters Projection map of the world? quercus robur

no, it is not at all the same from what I just saw (http://www.petersmap.com/page2.html, mercator on the right, Peters on the left). I left an example of the dymaxion map on the article page (see animation - ain't that pretty ?). If I understood well, one of the ideas is that no continent should be cut by the projection, that all terrestrial masses appear in one mass (?), and a better accuracy (less deformed than mercantur map in particular). User:anthere

List of links

http://worldgame.org/

saving links needed to work on this map

animation (free)

http://www.westnet.com/~crywalt/unfold.html

http://www.nous.org.uk/BFMAP.html

The first item is a piece of text (not a link), the second is in the article, and third is a general article on Fuller, not on his map. -º¡º

move your eyes at the top of this page. This article is part of a wikiproject. As such, a little bit more information is required.

And? Nothing was deleted from the talk, I was just commenting. -º¡º

Neutrality

Neutrality here? How about some negatives, like the fact that it confuses navigation (North is in the center, rather than at an extreme).

Yeah, agree. Why no negative points. Like "difficult to compare % of land and sea", "unability to quickly see tropical belt" etc. ? Peter S. 02:33, 10 October 2005 (UTC)

The fact that it's encumbered with copyrights and is not supposed to show nations as colored regions is a key disadvantage from the point of view of those wishing to publish political maps. Fortunately, many other mapping frameworks are available for this purpose.

Also, talking of seafaring nations - try to show on this map how Columbus found his way to America... — Preceding unsigned comment added by 119.98.18.179 (talk) 04:46, 24 November 2011 (UTC)

Alternative layouts

This icosahedral net shows connected oceans surrounding Antarctica

"There is no one 'correct' view of the Dymaxion map. Peeling the triangular faces of the icosahedron apart in one way results in an icosahedral net that shows an almost contiguous land mass comprising all of earth's continents - not groups of continents divided by oceans. Peeling the solid apart in a different way presents a view of the world dominated by connected oceans surrounded by land."

Would it be possible for someone to make an example of the second view,where oceans dominate?

Y Done.

So... how does the math work?

So... if I have the some coordinates of a point on a surface, how would I transform those points to find the coordinates of the corresponding position on a dymaxion map? (Pick one, though I am specifically interested in polyhedral dymaxion maps – let's say a dymaxion map based on a regular octohedron.) —Preceding unsigned comment added by 71.126.169.10 (talk) 22:52, 6 August 2008 (UTC)

Conformal?

An icosohedron has 20 faces. 20 separate stereographic projections—one for each of the 20 faces—would seem to be what's going on. That would make it conformal except at the 12 vertices. Can someone with experience with these maps comment on this? Michael Hardy (talk) 22:38, 17 October 2009 (UTC)

...Wait!... maybe it would be conformal except on the edges.

If so, that raises the question of whether there is some other way to do it that would make it conformal except at the vertices. Michael Hardy (talk) 22:56, 17 October 2009 (UTC)

....on the other hand one could project from the center of the sphere, rather from the point antipodal to the point of tangency, and that seems quite natural. But I don't know if it's conformal.... Michael Hardy (talk) 18:17, 18 October 2009 (UTC)

The radial projection (from the south hemisphere S₊ to C, seen as the tangent plane at the south pole) is not conformal. Reason : if it were conformal, we could compose the inverse of the radial projection, C → S₊, with the standard stereographic projection S → C; the result would be a radial holomorphic map C →C, that is, of the form f(re^it)=φ(r)e^it, which can be holomorphic only if f(z)=az, which is not the case here. Alternatively, it would be a bounded holomorphic map on C, hence constant by Liouville theorem, again not the case here. (moved from RD/M) --pma (talk) 08:04, 23 October 2009 (UTC)

"that raises the question of whether there is some other way to do it" Yes. Whatever particular projection the standard Dymaxion map uses, we can imagine developing some other map that is almost identical to the Dymaxion map, except it uses some other projection:

• I hear that Laurence P. Lee of New Zealand developed a conformal mapping that can be used to map spherical triangles to plane triangles. So yes, there is a way to make it conformal, except at the vertices. Is there any Wikipedia article that would be appropriate for posting the details of this projection?
• stereographic projection: each facet is conformal. Unfortunately, stereographic projection maps the 3 great circle arcs bounding each spherical triangle to 3 "lines" that gently curve (bulge out), so there's going to be a bit of mangling to make a straight-edged plane triangle; so I guess the edges are not exactly conformal.
• gnomonic projection -- one could project from the center of the sphere. That is used for *most* polygonal maps (but not the Dymaxion map). Alas, it is not conformal, as PMajer pointed out. It does have the great advantage that great circles map to straight lines, so spherical triangles map nicely to straight-edged plane triangles.
• the Chamberlin trimetric projection sounds very similar to the projection described for the Dymaxion map. Is there any significant difference?
• I hear that Irving Fisher developed an equal-area mapping that exactly covers the icosahedron; and John P. Snyder generalized that mapping, now called the Fisher/Snyder equal-area mapping. Alas, all equal-area mappings are not conformal, and vice versa. Is there any Wikipedia article that would be appropriate for posting the details of this projection?

--68.0.124.33 (talk) 23:08, 21 July 2010 (UTC)

This looks like supremely helpful information which ought to be in the article - I've just left a note over at Chamberlin trimetric projection querying whether that's the projection used for the Dymaxion. I think it'd be the most accurate - adjacent vertices would match up - but I'm no cartographer! Any chance of someone with a Big Book of Projections clarifying this in the article? 87.194.176.188 (talk) 17:24, 2 July 2011 (UTC)

File:Dymaxion 2003 animation small1.gif to appear as POTD soon

Hello! This is a note to let the editors of this article know that File:Dymaxion 2003 animation small1.gif will be appearing as picture of the day on June 5, 2011. You can view and edit the POTD blurb at Template:POTD/2011-06-05. If this article needs any attention or maintenance, it would be preferable if that could be done before its appearance on the Main Page so Wikipedia doesn't look bad. :) Thanks! howcheng {chat} 17:53, 2 June 2011 (UTC)

Picture of the day

An animation showing the unfolding of a Dymaxion map, a projection of a world map onto the surface of a polyhedron (in this case, an icosahedron) and then flattened to form a two-dimensional map which retains most of the relative proportional integrity of the globe map. This type of map was invented by Buckminster Fuller and is one of several of his inventions to use the name Dymaxion. Image: Chris Rywalt Archive – More featured pictures...