Re: More on: OGL View Matrix --> pfChan view matrix

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Alejandro Saez (cano++at++krusty.silicon.cl)
Fri, 12 Jun 1998 18:45:38 -0400

On Jun 12, 12:57pm, Angus Dorbie wrote:
> Subject: More on: OGL View Matrix --> pfChan view matrix
> More on model matrix inversion to viewing matrix.
>
> If anyone out there is curious about why transposing the
> model matrix worked instead of inverting the viewing matrix
> on the earlier thread (I got some questions) it's because
> they are equivalent operations for an orthogonal (I think
> that's the term) matrix.

There is something important to note: The name of the matrix is orthogonal but
also important is the type of transformation you apply to it. Affine
transformation (I think that's the name, I can't remember either) are
those that will keep a matrix orthogonal after being applied. Rotations are of
this kind, but there was a deal with scaling or non-uniform scaling and shears.
. Does anyone remember???.I'll go back to my CG notes and post it.

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Alejandro Saez
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