All these years, I thought the correct way to compute the cross product 
of two vectors is

   x3 = y1 z2 - z1 y2
   y3 = x1 z2 - z1 x2
   z3 = x1 y2 - y1 x2

But, apparently, I was wrong. The correct way is in fact

   x3 = y1 z2 - z1 y2
   y3 = z1 x2 - x1 z2
   z3 = x1 y2 - y1 x2

In particular, this results in y3 having the opposite sign. No wonder my 
program can't construct an orthogonal vector basis! >_<

FAIL.

The best part? I got this wrong in a library I released. Yes, my program 
is failing due to a bug in my own damned library... :'{

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*

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