Re: Non-square clipmaps

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Michael A. Coleman (mcoleman++at++txdirect.net)
Tue, 10 Mar 1998 10:45:13 -0600


perfly++at++segolene.roazhon.inra.fr wrote:
>
> Salut,
>
> is it possible to use non-square clipmaps ? (ex: 32768x8192)
>
> Kenavo
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One can stuff a non-square texture into a square clipmap; we had to do
this. Decide which square power of two you want to go to and then stuff
your image into half or fourth or eighth (or whatever your nearest
power-of-two aspect ratio is) of the cliptexture. Your image cache
files still have to refer to a square cliptexture. The trick is
positioning your eyepoint so that you never look at the areas of the
entire cliptexture that don't correspond to your actual image. We set
up blank tiles of various sizes to cover the "undefined" area of the
cliptexture.

There may be a better way to do this, but this is what we came up with.
We did this quite a bit of time ago, so my explanation is a little hazy.

Regards,

Michael A. Coleman
mcoleman++at++txdirect.net
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