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Dubbie
10-16-2008, 12:26 PM
I have a tricky problem that has me stumped.
I have two cubes, one that has been mirrored in x and y and thus has its row1 and row2 signs flipped in the transform matrix.

How can I distinguish between the two cubes based on their tansforms?
I first thought that the matrix determinant sign would tell me, but no, they are identical. Then I thought that I could take the "dot (cross x y) z" but no, that gives me the same result for both!

I feel I am missing something simple here.

attached is an image of the two cubes.

Thanks in advance for any help.
PEN
10-16-2008, 12:28 PM
When you flip two axes you still have a right handed matrix, what are you after if not that?
Dubbie
10-16-2008, 12:31 PM
hmm, right you are.

no wonder they appeared the same!

If I apply a normal map to both, they render different. I figured that was because of the mirroring.. Maybe I am barking up the wrong tree here

Thanks for the fast reply -

<edit>
this is why my simplified test scenes need to be exactly the same as my problem scenes.
I'm an idiot.
I think I need some sleep :)
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10-16-2008, 12:31 PM
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