Longitudinal seams on a UV sphere

Here is a global map in the form of an orange peel, also called gores (see attachment pangaeagores.jpg).

I want to make a UV sphere that I can unwrap to match the map. The sphere has 12 longitudinal rings. I’m not sure how I need to mark the seams, though. I am, you can tell by my presence, a mere n00b. Having a bit of a time with the selection process…eh, halp?

Thank you,

Clinton Crowley
Fort Worth, Texas

P.S. The Dymaxion Map of Buckminster Fuller (see attachment Dymaxion Map.jpg) would also be an interesting project to map onto a sphere.

Attachments



The paleogeographic map of the Jurassic period comes from Chris Scotese’s Paleomap Project:

http://www.scotese.com/

Building your mesh to fit a specific texture is VERY bad practice. The only way to make it work is to create a sphere with very specific dimensions depending on the relevant dimensions of your texture (i mean distances from the points to the crevasses in that image and the thickness of individual segments). Chances are your UVs will end up distorting the image. Unless you can obtain some information on what kind of sphere that image is useful for you’ll have problems. There are other earth textures out there. AFAIK Nasa provides Mercator Projection textures. These are a lot easier to use since you only need to create one longitudonal seam from top to bottom. Have a search through google. IIRC there are some very good free mercator images out there. Hope that helps.

EDIT
Don’t worry about copyright. All NASA material is in the public domain.

EDIT 2
I just noticed that image is of earth from the Jurassic period. Looks like you’re screwed. All i can suggest is trial and error.

EDIT 3
Both of those images look like they’re simply maps anyway and pretty useless as texture. The dynamaxion projections will create a LOT of ugly seams and the other one has black coutours and so is absolutely useless. The best thing I can suggest is to unwrap a sphere and paint the texture yourself.

Generically that may be true. But there’s nothing silly about wanting to unwrap a UV sphere into regular gores.

Start with a UV sphere with 12 segments and 8 or 12 rings. Delete all except one segment. Load your texture into a UV window, and then unwrap the segment (in the 3D window: A,U). Move the two pole vertices to overlay the poles of the top or bottom gore, and pin them.


Unwrap everything again. One gore done.
In a top view 3D window, select everything (A), duplicate (Shift D) and rotate ® by 30 degrees. With the new vertices still selected, go back to the UV window and move them in the Y direction by the width of a gore. Two gores done.



Repeat for the third gore.
Select everything in 3D, duplicate and rotate by 90. Slide the UVs by three gores.
Finally, select everything, duplicate and rotate by 180. Slide the UVs.



You may need to tweak the Y position of some of the individual gores. Once you are happy with them all, select everything and remove doubles.


Best wishes,
Matthew

Thank you both for the in-depth responses! I’ll give both methods a try. I can get Mercator versions of the Jurassic from the guy who makes the maps, so it’ll be possible one way or the other.

Thanks again,

Clint