Dymaxion projection?

[poelzi]

The Dymaxion map projection would be utterly awesome :)

[Fil]

it's already there, by @jasondavies

https://www.jasondavies.com/maps/airocean/
d3/d3-plugins#61

[jrus]

That one uses a Gnomonic projection, not Fuller’s.

[Fil]

Are we able to include this for #32? Would make a nice addition

[mbostock]

Doubtful. It looks like Jason has taken down the code (which as far as I know was never released under an open-source license).

[jrus]

Papers:

• Robert W. Gray (1994). “Fuller's Dymaxion Map”. Cartography and Geographic Information Systems 21 (4). http://www.tandfonline.com/doi/10.1559/152304094782540628
• Robert W. Gray (1995). “Exact Transformation Equations for Fuller's World Map”. Cartographica 32 (3). http://www.utpjournals.press/doi/10.3138/1677-3273-Q862-1885
• John E. Crider (2008). “Exact Equations for Fuller's Map Projection and Inverse”. Cartographica 43 (1). http://www.utpjournals.press/doi/10.3138/carto.43.1.67
• Richard Buckminster Fuller (1944). “Cartography”. US Patent 2,393,676. https://www.google.com/patents/US2393676

[Fil]

https://www.openstreetmap.org/user/smaprs/diary/39829

Dymaxion C/Python script at: http://emergentweirdness.blogspot.fi/2012/03/dymaxion-conversion.html

[curran]

Would be a sweet projection to have available.

@Fil Following links from that emergentwierdness link, I tracked down this quasi-README for the C code that implements the projection by Robert W. Gray.

Some interesting images from there:

These seem to be a map of sorts for navigating his C implementation of the Dymaxion projection.

Maybe this C implementation could be a useful blueprint. Note the license:

/**************************************************************/
/*                                                            */
/* This C program is copyrighted by  Robert W. Gray and may   */
/* not be used in ANY for-profit project without written      */
/* permission.                                                */
/*                                                            */
/**************************************************************/

Also related to OSGeo/PROJ#232 Add Dymaxion/Fuller Projection which, interestingly, links to this JavaScript implementation of the Dymaxion projection that appears to have been added to that repo by @mbostock . Here's a working JavaScript Dymaxion choropleth that uses that implementation with Protovis (source).

[mbostock]

That was contributed by Vadim Ogievetsky, and I believe it was a direct port from the C code you linked, and therefore is missing appropriate attribution. I will add attribution shortly.

[mbostock]

Attribution added in mbostock/protovis@b653a8c.

[Fil]

Now fully implemented in d3-geo-polygon(newprojections branch), but it needs a new release of d3-geo (d3/d3-geo#128) before it's usable.

[Fil]

Now fully implemented in d3-geo-polygon.

To avoid any IP issue I made a fresh implementation of the triangle transformation, and avoided the (possibly though not probably) trademarked name "Dymaxion".

https://beta.observablehq.com/@fil/airocean-projection
https://beta.observablehq.com/@fil/buckminster-fullers-triangle-transformation

[mbostock]

Looks great, @Fil! My only suggestion is to rotate it 90° so it’s bigger on tall screens (as Jason did previously).

[Fil]

Arguments in favor of keeping this as the standard orientation: 1. it fits 960x500 better 2. same as https://www.bfi.org/about-fuller/big-ideas/dymaxion-world/ dymaxion-map and Jasper Johns's painting.

[mbostock]

I didn’t mean to make that the default, I just meant in your demo…