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Outerra Tech Demo download. Help with graphics driver issues

Author Topic: Sphere in Outerra  (Read 3242 times)

montify

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Sphere in Outerra
« on: April 14, 2014, 10:57:55 am »

Hello Outerra.


Do you use the cube2sphere Mapping for Outerra? (like normalize the Vector around the Origin, OR the Mathproof Version http://mathproofs.blogspot.co.at/2005/07/mapping-cube-to-sphere.html)

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cameni

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Re: Sphere in Outerra
« Reply #1 on: April 15, 2014, 04:27:41 am »

Neither, they aren't regular enough.
We are normalizing vector <u, v, 1 + (0.5/(√2 - 1) - 1)∙(1 - u²)∙(1 - v²)>, where u,v are face coordinates in -1..1. This gives pretty homogenous spacing, but the inverse has to be found by Newton solver. Luckily, it's only rarely used in practice, so it's not a problem.
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