

Visualizing the cross product between two vectors - taylorbuley
http://1ucasvb.tumblr.com/post/76812811092/given-two-vectors-in-three-dimensions-one-can

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United857
I've always found the parallelogram-area interpretation to be the easiest to
intuit about:

[http://en.wikipedia.org/wiki/Cross_product#Geometric_meaning](http://en.wikipedia.org/wiki/Cross_product#Geometric_meaning)

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Jach
Boo cross products. [http://www.av8n.com/physics/clifford-intro.htm#hi-
stamp](http://www.av8n.com/physics/clifford-intro.htm#hi-stamp)

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gfodor
well, i just discovered a new thing. thanks! any recommended texts/papers on
this subject (geometric algebra) as applied to computer graphics? I see there
are basically 3 books on amazon.

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defen
I've had good luck with this one: [http://www.amazon.com/Geometric-Algebra-
Computer-Science-Rev...](http://www.amazon.com/Geometric-Algebra-Computer-
Science-Revised/dp/0123749425) They definitely explain why the cross product
is an ugly hack :)

The authors have a website - geometricalgebra.net - where you can download a
program which will display all the diagrams from the book and allow you to
manipulate them. You can also render arbitrary low-dimensional geometric
algebra constructions which helps tremendously with improving your intuition
about how things work. I'd say it's at a middle ground of mathematical
sophistication - it's a good mix of proofs and practical usage. It's almost
entirely dedicated to applying geometric algebra to computer graphics, so you
won't get as much out of it if you're interested in applications to physics,
or just pure mathematics.

If nothing else, I finally know what a quaternion _really_ is after going
through this book.

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sp332
Why does theta θ look so weird in that font?

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Zikes
According to the wikipedia page[1] that's a valid way of displaying lowercase
theta.

[1] [http://en.wikipedia.org/wiki/Theta](http://en.wikipedia.org/wiki/Theta)

