basically i have a problem where i am rotating 1 vector to be parallel to another(adsbygoogle = window.adsbygoogle || []).push({});

i get the axis of rotation by the cross product of the 2 vectors

the angle by the arctangent of the magnitude of the axis and the dot product of the 2 vectors

however

arctangent2(magnitude(axis) , dotproduct(vector1,vector2))

is quite intensive I BELIEVE BECAUSE magnitude is a sqr root.

i'm wondering if could just do some kind of axis squared and dot product square or something

and still get the right angle.

Hope this makes sense.

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# Arctangent2 without square rooting?

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