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Thread: How to create a pole-shifted map of Earth?

  1. #1

    Question How to create a pole-shifted map of Earth?

    It's been a while since I've posted here, but I've come across an especially tricky problem which I hope the experts here can solve. You see, for one of my projects I want to create a map of Earth... after a Pole Shift.

    That is to say, I want to leave the positions of the continents largely intact, but I want to place the North and South poles at different locations. For instance, the North Pole might be at the position of the Arab peninsula - and then it would be located at the very top of the map (in a conventional map projection, that is).

    This is hardly the first time someone had this idea - this site has a bunch of pole-shifted maps of Earth:





    But unfortunately, if the author explains somewhere how he created those maps I couldn't find it.

    And I feel that this should be the kind of problem for which a software solution should exist. There is already a software that can transform map projections - G.Projector from NASA. Unfortunately, the only map input format it accepts is an equirectangular projection:



    Which, like any other map projection out there, distorts the shape and size of the land masses (especially near the poles).

    So... does anyone here know of a reasonably simple way for creating a pole-shifted map of Earth? Ideally, I'd like to try out a bunch of different shifts...

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    Guild Artisan su_liam's Avatar
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    Guild Grand Master Azélor's Avatar
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    He probably painted a real 3D sphere like this one : http://www.cartographersguild.com/sh...ad.php?t=30877

    Some might be able to provide more concise help by I tried to change the location of the pole with several software on different map projection and it's pretty limited.

    Some work with Gprojector:

    Molweide oblique
    Hammer oblique
    Orthographic (it's a sphere seen in 2D)
    Dymaxion (not available with Gprojector)

    There are other as well if you look into the available projections in the software but the distort the world a lot.

    I don't know what is your actual map projection but equirectangular works as the input for most software because it's very easy to re-project it. Some projections can be re-projected but only with great approximations, like Winkel Triple.

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    Administrator waldronate's Avatar
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    I remember reading the World Dream Bank site years ago and he had mentioned the use of a real globe, plaster for landforms, and acrylic paint for colors. I couldn't find the description page when I took a quick glance just now, though.

    I suppose I really ought to update the ancient ReprojectImage software ( http://fracterra.com/ReprojectImage.zip ) that I wrote years ago to convert various projections to Equirectangular. If I get around to doing the other half (project from Equirectangular to other projections), then it would make a nice general reprojection thing.

    On the Winkel Tripel inverse subject, I suppose that fractional millimeter errors could be considered "great approximations" by some, but they are probably acceptable in practice for most purposes.

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