In article <3fc5593f@news.povray.org>, Warp <war### [at] tagpovrayorg> 
wrote:

> Christopher James Huff <cja### [at] earthlinknet> wrote:
> > The transformations possible 
> > in POV are scaling (including reflection), rotation, translation, 
> > shearing, and combinations of these.
> 
>   Actually any shearing can be nade as a combination of rotations and
> (uneven) scales, so technically it's not an independent transformation
> in itself... :)

True, but is is rather different conceptually, which is why I usually 
mention it as a "fourth" transformation. These are just conventions, a 
human categorization. You could say a rotation is just a reorientation, 
or that they are all just matrix multiplications...

BTW, in linear algebra, the transformations are often broken down as: 
contract (scale by a value < 1), dilate or expand (scale by value > 1), 
reflect (scale by -1 on an axis), rotate and translate.

-- 
Christopher James Huff <cja### [at] earthlinknet>
http://home.earthlink.net/~cjameshuff/
POV-Ray TAG: chr### [at] tagpovrayorg
http://tag.povray.org/

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