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A comment on Geometric Algebra (2012). Parent comment

Re:Geometric Algebra (2012) by creata on Monday November 30, 2020 @03:56AM (#25251957)
I'm not sure what you mean. Let Ax mean rotating x by A (which is a rotation matrix, quaternion, rotor, whatever). Then, the composition of Ax + b and Cx + d is

    C(Ax + b) + d = (CA)x + (Cb + d).
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Re:Geometric Algebra (2012) by hohohmm on Monday November 30, 2020 @04:00AM (#25251982)
yes but what about non-uniform scaling. Is it possible to handle it in this case?
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Re:Geometric Algebra (2012) by creata on Monday November 30, 2020 @04:10AM (#25252027)
Not with just a rotor (quaternion) and an offset, or with motors (dual quaternions). If you want nonuniform scaling, rotation and translation, then matrices are probably the nicest way to do that.
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