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Re: [1.2T-LC] inverse and constrained transformations

From: David Woolley <forums@david-woolley.me.uk>
Date: Sun, 28 Sep 2008 18:40:45 +0100
Message-ID: <48DFC19D.7050004@david-woolley.me.uk>
To: www-svg@w3.org

Dr. Olaf Hoffmann wrote:
> David Woolley:
> 
>> Can you provide a concrete example.  I would have thought that, if the 
>> inverse didn't exist, there will always be points that don't have a 
>> unique image when the transform is reversed.
> 
> 
> If the determinant of the transformation matrix is zero, 
> 2-dimensional and 1-dimensional structures are mapped
> to 1-dimensional structures or points. Just looking at the
> result, it is not possible to reverse such transformation,
> it is not a bijective function, just surjective.

That was my point.  There is no way of inverting the transform, even if 
one works with the individual steps, not just the matrix.


-- 
David Woolley
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Received on Sunday, 28 September 2008 17:41:33 GMT

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