question: lookat() command and twist

[DanKarron at UCBVAX.BERKELEY.EDU]

The twisting artifact in lookat() can be avoided by using a negative reverse
sequence of modeling transformations to specify your eye position and
vector.

This is the same as specifying your eye in worldspace and inverting
the matrix to give your the eye position viewing transform for that
eye position.

If this is unclear, I can post a long explanation. The short version
is to use modeling transforms for your eye position.


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