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Comment by jengamaster | Hacker News Reader

Very cool result! I've been wondering about applying the height-maps that you get from Perlin/Simplex directly to the vertices of a planet, for 3D terrain. I'd imagine that the cube mapping approach might not be perfect for this because of the irregular distance between vertices. The geodesic dome would probably work, but I have no idea how you would generate noise for a shape like that.

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I've used a cubemap approach to render procedurally generated asteroid geometry and it works pretty well. I start by generating the heightmap using 3D simplex noise, Then when rendering I use a domain shader to offset the vertices of an icosphere along the normal vector according the the height in the heightmap.

http://imgur.com/rpKalpk

I've got a bunch of other procedural content generation blog entries over at http://www.junkship.net, including this entry http://www.junkship.net/News/2011/11/13/building-steam-with-... which covers a lot of similar ground to the parent article.

That's an impressive result! My worry was that it would become more obvious if I were to skimp on the poly count of the shape. Doesn't seem to have been an issue for you.

Thanks for the links, I'll definitely check them out.

You'd actually generate noise just the same way as I used 3D Simplex noise.

I am unsure on UV mapping though as I have not experimented with it yet when using geodesics. Instead I just escaped the problem by using a collapsed cube :)

Ahh, I get it. Took me a couple reads of the code to see what was going on, but that is pretty cool. Thanks for the info!

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