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I'm new to Blender 2.79. I'm trying to map an equirectangular image of the night sky (pictured below) onto an icosphere.

starmap equirectangular

The problem is, every time I manage to create a material and/or texture for the icosphere, it wraps only part of the way around the object. Pictured below is as far as I can get, with a color-inverted version of the texture so you can see better what's going on.

screencap 1

Any help would be very much appreciated!

Thanks :)

Rúnatál Davino
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3 Answers3

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I don't know how you could correctly unwrap an icosphere but you could do it another way around with an UV sphere, an icosphere, and a Shrinkwrap modifier:

  • Create an UV sphere.
  • Select all except the two poles and Unwrap > Sphere Projection mode, with Align to Object option.
  • Select the 2 poles and make a simple unwrap.
  • Prepare your material.
  • It works, your drawing is projected on your UV sphere.
  • In Object mode, create an icosphere within your UV sphere.
  • Give your UV sphere a Shrinkwrap modifier and choose the icosphere as Target.
  • Give your UV sphere one or probably 2 Subsurf modifiers, one above, one below the Shrinkwrap modifier. Test the best solution, and the best Subdivision values, it looks like an amount of 3 is necessary on the top Subsurf.
  • Now, thanks to the Shrinkwrap, your UV sphere has taken the shape of the icosphere, you should have the result you want.

enter image description here

moonboots
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  • this is an awesome work around, thank you! do you know of a way I can map the UV directly as an equirectangular projection? your method distorts the poles. – Rúnatál Davino Apr 04 '19 at 13:45
  • maybe in the UV Editor you could try to move the UV top and bottom edges a bit, with the proportional editing enabled? or maybe try this method: https://blender.stackexchange.com/questions/24043/how-to-animate-morphing-a-rectangular-plane-into-a-sphere/24053#24053 I don't know if it will fix the problem... – moonboots Apr 04 '19 at 13:57
  • If you remove the poles of a UV sphere, add a longitudinal seam, and unwrap with 'spherical projection' from an orthogonal view, poles top and bottom, you don't need the add-on. But I've been struggling to find a way to bake from the sphere to the geodesic, without discontinuity across the geodesic's edges.. tried a lot of things.. cages.. subdividing, including UV's at various stages.. no luck yet... – Robin Betts Apr 04 '19 at 16:48
  • ok my bad, I've edited, no need for UV square addon actually ;) – moonboots Apr 05 '19 at 05:11
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enter image description here

All you need is use Environmental texture node for image.

All credits goes to lemon (original post).

vklidu
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0

I think you still have the light set as a point, which will only illuminate a certain area of the object facing the point.

Change the material to shadeless or add some hemi lamps to illuminate more of your object so you can see if your problem really does exist.

Duarte Farrajota Ramos
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JakoNintenCraft
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