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[Gene Keyes]

2011-12-16

In an earlier thread, I introduced my work on B.J.S. Cahill's octahedral world map projection, via a detailed critique of Buckminster Fuller's Dymaxion map, as compared to Cahill's; and likewise of Steve Waterman's recent octahedral maps. I also mentioned my own modification, the Cahill-Keyes Octant Graticule.

Now I am seeking input -- both programming and/or GIS content -- for a long term project I've been nurturing since 1975: a 1/1,000,000 Megamap in the Cahill-Keyes octahedral layout, plus smaller versions of the same thing, down to 1/200,000,000 or less, and any number of derivative maps.

This is a hobbyhorse, not a commercial venture. I hope it to be an open-source world map archetype for a wide variety of uses, from the simplest outline or grade school map, to the most elaborate global data display, and mashups I can hardly imagine. (I'd copyrighted the basic design of the map and graticule, but put this larger effort in Creative Commons.) The detailed exposition of that design can be found here (plus other links therein):

Cahill-Keyes Octant Graticule: Principles and Specifications, with Perl programs and OpenOffice.org 2.0 macros for 1/1,000,000 Megamap

Gene Keyes
2010-08-20

Abstract

How a complete one-degree graticule of an eight-octant world map at 1/1,000,000 is made with Perl and macros in a free OpenOffice.org 2.0 vector-drawing program on a $300 Asus netbook. This is another installment of my drafting notes for the Cahill-Keyes "Real-World" map. It describes only the graticule, in intricate detail, both as hand or computer drawn archetypes. Inputting GIS data is the next challenge.

******************** UPDATE

On 2011-01-12, I posted an additional section, further elaborating the Perl Program, with some trial coastlines of Prince Edward Island, and Nova Scotia.

Toward a Computerized World Coastline for the Cahill-Keyes Octant Graticule

Excerpt:

In the first six web-pages of the above "Principles and Specifications", dated 2010-08-20, I showed how my companion Mary Jo Graça had devised two interconnected Perl programs and some OpenOffice.org Draw macros, which can output a complete Cahill-Keyes 8-octant graticule (or segments thereof), at 1/1,000,000 or less, with proportional 1° geocells, and a threefold metric grid enclosure.

Since then, she has been striving to amplify the program set to explain her approach in greater detail (with six illustrations), and to incorporate world coastline data. Besides the earlier graticule, she has now been able to do a specimen depicting Nova Scotia and Prince Edward Island at 1/1,000,000 or smaller (using a 1/2,000,000 data segment from NOAA): http://rimmer.ngdc.noaa.gov/mgg/coast/

However, the programming still remains at an early stage, and now comprises a patchwork of three interrelated Perl programs and separate OOo macros, the latter entailing a lot of clumsy cut-and-paste of large data sets. In Mary Jo’s opinion, these remain incomplete and unready for prime time, and could all be consolidated into a much more efficient single program, perhaps written in Python, or C++, or directly into the Basic of OOo macros. So far, that has been beyond her reach.

Nonetheless, I want to put forward the current state of our progress, in the hope that those who are interested can streamline the scripting, and utilize other GIS data.

To repeat: this is a nonprofit, for-the-fun-of-it venture. Contact gene.keyes at gmail.


Here are a few illustrations (stated scale varies depending on your monitor). There are a lot more where these came from.



A 1980 prototype (hand-made by GK in 1980)
 1975_Cahill_Keyes543x540px.jpg   97.08K   36 downloads

The graticule and grid at 1/200 M
(programmed by Mary Jo Graça in 2010)
 CKOG_8.jpg   114.06K   31 downloads

Specimen coastline at 1/1 M
(programmed by Mary Jo Graça in 2010)
 PEI_NS_1_1M_CKOG_.jpg   75.1K   27 downloads

Specimen coastline at 1/5 M
(programmed by Mary Jo Graça in 2010)
 PEI_NS_1_5M_CKOG_.jpg   129.75K   29 downloads

Two of six diagrams by Mary Jo Graça (2010) showing her x-y conversion approach
 Cahill_Keyes_diagram_fig_1.jpg   129.83K   31 downloads  Cahill_Keyes_diagram_fig_2.jpg   130.21K   31 downloads