Calculating adjacent quads on a quad sphere

Posted by Caius Eugene on Game Development See other posts from Game Development or by Caius Eugene
Published on 2013-09-27T17:37:04Z Indexed on 2014/06/02 21:50 UTC
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quadtree

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sphere

I've been experimenting with generating a quad sphere. This sphere subdivides into a quadtree structure. Eventually I'm going to be applying some simplex noise to the vertices of each face to create a terrain like surface.

To solve the issue of cracks I want to be able to apply a geomitmap technique of triangle fanning on the edges of each quad, but in order to know the subdivision level of the adjacent quads I need to identify which quads are adjacent to each other.

Does anyone know any approaches to computing and storing these adjacent quads for quick lookup?

Also It's important that I know which direction they are in so I can easily adjust the correct edge.

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