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Re: frozen value for discrete animation

From: Dr. Olaf Hoffmann <Dr.O.Hoffmann@gmx.de>
Date: Fri, 25 May 2007 18:39:57 +0200
To: www-smil@w3.org, cogit@ludicrum.org, sjoerd@acm.org
Message-Id: <200705251839.57280.Dr.O.Hoffmann@gmx.de>

Hello,
>
> I propose to change the wording to "integral multiple" to make it clear
> that we're talking about proper multiples here.  Alternatively, we could
> just leave out the word "even", but I think (as apparently the original
> author did also) that an extra adjective should make it even clearer.
>
> Sjoerd (member of the SYMM working group, so in a position to effect the
> change)
>

I think this can avoid some confusion. The given formulars
seem to be sufficient even without an additional adjective.

What I found about this at wikipedia:
'The integral value of a real number x is defined as the largest 
integer which is less than, or equal to, x, see floor function.'

Hmmm. The formular 
'AD = d*i for some positive integer i'
seems to be the important part of it to get 
proper implementations.

And what about the 'frozen value for discrete animation'?
I still think, this is different in SMIL2 as with the old 
SMIL animation recommendation or in SVG. They have
only the time interval model and 
'freeze the effect value at the last value of the active duration'.

For this example:
calcMode="discrete"
values="1;2;3"
keyTimes="0;0.4;0.8"
begin="0s"
dur="10s"
end="4s"
fill="freeze"

Because a time interval is exclusive end, the last value is 1
and not 2 for the old SMIL animation recommendation or in SVG.
With the SMIL2 timing modul it will get 1 with the 'cut off simple 
duration' or 3 with the 'dur value simple duration'. 
With the animation modul again it depends on the interpretation
of 'simple duration', the 'dur value simple duration' may result in
applicable formulars resulting in 2 (?), not really fitting to the
time interval model, with the 'cut off simple duration' the
formulars are not applicable anymore. 
But if in the animation modul 'simple duration' has another
meaning as in the timing modul, the fill attribute is not
well defined for animation anymore. Understandable that
for example the CR SVGT1.2 still uses the old definition for
the fill attribute. 
Received on Friday, 25 May 2007 16:53:43 GMT

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