W3C home > Mailing lists > Public > www-svg@w3.org > March 2011

Re: Proposal: Change end attribute behaviour

From: Dr. Olaf Hoffmann <Dr.O.Hoffmann@gmx.de>
Date: Fri, 25 Mar 2011 11:38:06 +0100
To: www-svg@w3.org
Message-Id: <201103251138.06785.Dr.O.Hoffmann@gmx.de>
Brian Birtles:

>I would like to propose an amendment to SVG regarding the behaviour of
>the end attribute.
>
>Currently SMIL 3.0 requires that, when establishing an interval, if an
>end-attribute is specified then either:
...

Wouldn't it be better to discuss this with the SYMM group?
Would have been more effective to discuss the general concept before
SMIL 2 or 3 have been published as recommendations ;o)

I think, it does not help to deviate in SVG from SMIL just for fun and
after 10 years with a behaviour already defined otherwise. The purpose of
recommendations is, that one can rely on them, if the behaviour is
often changed, for authors it simply means, that the changed feature
or the complete recommenation cannot be used at all - this impression
should be avoided to help authors to believe in SVG and that it can
be really used for published documents not just for the moment, but
for many years and in the future as well. Nobody really wants to check
all published documents every year to new recommendations to be
sure, that nothing was changed that modified the meaning of already
published documents. It is annoying to have to fixed issues due to
modified recommendations (what should be limited to contradictory
or undefined issues).

>I find this to be confusing for authors as the presence of a single
>end time or end instance changes the behaviour considerably:
>
>  <animate begin="1s; 3s" ... /> --> 2 intervals
>  <animate begin="1s; 3s" end="2s" .../> --> 1 interval
>
>Furthermore, the behaviour will differ if we have end="a.begin" versus
>end="a.beginEvent" since only the latter has event conditions.
>
>Also, in the second case, even with beginElement() it is impossible to
>start the animation after t=2s.

simply use <animate begin="1s; 3s" end="2s; indefinite" .../>
...


Olaf
Received on Friday, 25 March 2011 10:38:42 GMT

This archive was generated by hypermail 2.3.1 : Friday, 8 March 2013 15:54:47 GMT