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Arachanox
07-13-2009, 12:08 PM
Hello, I've been wandering around this site for a while and making a few rough maps in GIMP for fun, but now I want to start working on a world map. I've read some good information like A Magical Society: Guide to Mapping and some other helpful stuff, but my issue is dealing with map projections. If I just go and make a rectangular map the way I want the world to look, that doesn't mean it would realistically translate into a spherical planet, due to how the image skews and has to be torn apart to become a sphere.

Is there any method or program which I can use to see how various maps would look when translated on to a sphere?

Thanks, Arachanox.

töff
07-13-2009, 12:15 PM
Most 3D apps will wrap a 1x2 rectangle onto a sphere.
(It's sometimes tricky to get the poles right because of the distortion.)

Post a 1x2 and I'll sphere-map it for you, no charge.

edit: By 1x2, I mean it's twice as wide as it is high. The north pole is the top edge, the equator runs horizontally through the middle, and the south pole is the bottom edge. It's basically a Mercator.

Arachanox
07-13-2009, 01:05 PM
Thanks for your offer, but I haven't actually started on my world map because I want to experiment with random images before going through the effort of mapmaking only to find that it looks bad on a sphere.

Rather, what program do you use to map the image onto a sphere? If I could get it myself I could run a whole bunch of tests without having to trouble you or anyone else to do it for me :)

Thanks, Arachanox.

töff
07-13-2009, 01:36 PM
Any 3D app will do it.
I use 3DSmax, which is expensive and difficult.
I have also used Bryce, which is cheap and easy.
There's also Blender, which is free and only moderately difficult.

RobA
07-13-2009, 02:27 PM
Gimp itself can wrap your 1:2 image onto a sphere to test how it looks. Another easy method is to pull it into google earth.

-Rob A>

Arachanox
07-13-2009, 02:28 PM
You have been really helpful, töff! I am already making 2x1 pictures and putting them into Bryce, seeing how they become distorted and how it will affect my mapmaking. Thank you very much for your help!

Edit: Eh? I have been using GIMP for some basic rudimentary mapmaking but I have never seen anything that would turn an image into a sphere. How can I go about doing this in GIMP?

Edit2: I have figured it out after 30 seconds of actually looking. >_< Thank you as well, RobA! I never knew GIMP could do that so I had never looked.

altasilvapuer
07-14-2009, 12:21 AM
Naeddyr has a tutorial in the tutorial forum for something highly similar to this, as I recall. Let me see if I can find it.

Ah, here it is:
http://www.cartographersguild.com/showthread.php?t=5025

This is the projection we're all talking about, by the way: http://en.wikipedia.org/wiki/Equirectangular_projection

I don't know too much about projections, though. Naeddyr seems to be the resident projection-nut, from what I've seen, so I'd ask him.

-asp