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Direction of cross product vector is wrong

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  1. 2005-04-17 23:56:48 UTC
    Cross product is a mathematical convention where X, Y and Z are concerned

    Given one conventional definition for the crossproduct x, we have
    X = Y x Z
    Y = Z x X
    Z = X x Y

    Drawing axes is also another convention, a pictorial one. If you use the crossproduct convention above (purely mathematical) with a pictorial convention similar to DirectX (the coordinate system is stated with y upwards, x to the right and z forward) then the mathematical convention must be represented by the pictorial convention, eg AxB = C and like X x Y= Z then C must be in the same picture representation as Z.

    Note you can change the pictorial convention without changing the mathematical convetion. If OpenGl coordinate system is used then it is a mirror picture of the DirectX system, but C and Z still coincides.

    Note you could change the mathematical convention
    X = Z x Y
    Y = X x Z
    Z = Y x X
    Here mathematically the result is different

    Everything is ok when you stick to one convention throughout your representation :) I have not read through all of the context from
    http://www.euclideanspace.com/maths/algebra/vectors/
    but the diagram is just on element out of the entire context, so I cant agree or disagree with you
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