On Tue, 4 Jul 2000 04:36:38 +1200, Ian Witham wrote...
> Hi all...
> recently I was confronted with a bit of a brain teaser:  When a cube is spun
> about the axis of it's two opposite corners what is the shape of the space
> it passes through?
> I had a few bright idea's.. some of them pretty accurate.. but before long I
> decided to test the result.
> The resulting shape is fairly intriguing so I thought it may be worth
> sharing.
> BTW.. just try placing a POV cube so that two opposite corners lie on the y
> axis. It's trickier than it sounds.

You could have just asked what a spun cube looked like.  Anyone who's 
ever played roleplaying games (AD&D (Yech!), Call Of Cthulhu, Runequest, 
etc.) and gotten bored would have been able to tell you that the answer 
is a SOR with a profile of a sort of waisted equilateral diamond.

Well, that made no sense.  Go find a six sided dice, and spin in on a 
flat surface.  It'll probably take a hell of a lot longer than it took 
you to do the maths, write the scene file and render it...

<grin>

Oh, and I figured it out using a pencil, paper and calculator, and the 
rotations I came out with were <45.0,0.0,35.26439>.  This was using 
nothing more complicated than basic trigonometry and Pythagoras' theorem.

Bye for now.
     Jamie.

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