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mphanke
04-17-2002, 05:14 AM
Hi,

short question:

If I have a normal in a certain vertex, and then rotate the vertex, do I have to rotate the normal too??
I mean physically rotate it in 3D-space with sin and so on. Like rotating around Z-Axis 90. From my point of view I don't have to rotate the normal since it is situated perpendicular to a vertex, right??

I'm a little confused about this topic since the last discussion with a colleague.

Thanks,

Martin

Bob
04-17-2002, 05:47 AM
The normal should be rotated with the object. If you rotate your object with OpenGL's own matrix functions, the normal will automatically be rotated.

mphanke
04-17-2002, 05:52 AM
Thanks Bob for solving this mysterie!

Martin