W3C home > Mailing lists > Public > www-svg@w3.org > September 2008

[1.2T-LC] inverse and constrained transformations

From: Dr. Olaf Hoffmann <Dr.O.Hoffmann@gmx.de>
Date: Sat, 27 Sep 2008 17:53:20 +0200
To: www-svg@w3.org
Message-Id: <200809271753.20302.Dr.O.Hoffmann@gmx.de>

Hello SVG WG,

the section 7.7 about constrained transformations mentions
several times the inverse of the CTM. Obviously this does
not always exist (if the determinant is zero).
Is it really intended, that this inverse matrix is used by 
implementations to get the desired effect or is it expected, 
that the effect is gained with other methods (what should be 
always possible even without using the not always existing 
inverse matrix, because the document contains much more 
information about the transformations than only the CTM)?

But if it is really expected, that the inverse matrix
is used, what is the expected behaviour, if it does not exist,
for example for a short time within an animation or due to
some tricky things using the vector-effect non-scaling-stroke.
To mention this would be important especially for authors,
because then they have to compute and avoid such situations.
If another method is used, they do not really have to care.


Olaf
Received on Saturday, 27 September 2008 16:09:50 GMT

This archive was generated by hypermail 2.3.1 : Friday, 8 March 2013 15:54:40 GMT