Re:How Quaternions encode rotations: derivation and sample code
by UlyssesSKrunk on Wednesday September 07, 2016 @02:48PM
(#12445968)
So in 3d that becomes 3(2)/2 = 3. Quaternions have 4 parts. That's what has always made it hard for me to understand.
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Re:How Quaternions encode rotations: derivation and sample code
by Sharlin on Wednesday September 07, 2016 @11:19PM
(#12450048)
And in 2D it is 1 but complex numbers have two parts. As I tried to explain, there's simply some redundancy in the representations because it's just unit complex numbers/quaternions that we're interested in. We accept that because it makes the math prettier. Heck, matrices, the de facto standard for representing rotations, have much more redundancy - four and nine elements in 2D and 3D respectively.