Re: scaling and normals

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Angus Dorbie (dorbie++at++sgi.com)
Wed, 17 Feb 1999 18:25:33 -0800

Just rescale the vertex coordinate attributes in the geoset, this should
leave the normals alone.

If you use a DCS then OpenGL will do the 'right' thing and scale the
normals (using the inverse scaling matrix?).

Cheers,Angus.

Ken Lindsay wrote:
>
> hi,
>
> does anyone have a good trick for scaling geometry but leaving surface
> normals as they are? or is this the way that DCS/pfMatrix mechanix work
> anyway? my task is to reduce the height of some terrain, but to try to
> keep the dramatic lighting it has when it is tall. my past experience
> with this shows a flattening of the lighting effect when i scale down
> the height.
>
> thanks
>
> ken
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> ken "fire a few neurons" lindsay kl++at++ptolemy.arc.nasa.gov
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