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Re: About "d" attribute

From: 向雅 <fyaoxy@gmail.com>
Date: Sat, 12 May 2012 00:40:41 +0800
Message-ID: <CAJH9WWR=2OvZm5BUW29d1Q2Bh_FiJEAxLJTOW4opfjgMTcpTSw@mail.gmail.com>
To: "Dr. Olaf Hoffmann" <Dr.O.Hoffmann@gmx.de>
Cc: www-svg@w3.org
Indeed, there already have implicit conclusion:
In normal use cases, the empty path not a necessary.

Seems, at this point, both agree:)

now we are talk about it's necessary in non-normal uses.
>From common programming view, if there is an empty thing, so the
iteration loop must do checking out if something is special or null
like, yes?
But in a graphics context, this kind of verification will eat some
machine time. so value at where?

But:) I must admit, I not really do some kind of animation framework.
and I think my animation part processing about to begin.
Maybe after some additional experiments, I have more qualification to
talk about that from animation applying view.:)


致敬
向雅


2012/5/11 Dr. Olaf Hoffmann <Dr.O.Hoffmann@gmx.de>:
> With declarative animation one can have a values list in
> SVG tiny 1.2 and 1.1.2 for the d attribute with different
> numbers of path segments to get a discrete animation.
> If an author sometimes needs no path as one value -
> why not? If this results in no display, there is no need
> for an additional synchonised animation of another
> property or attribute to get the intended effect.
>
> Obviously one can use the use element with
> a declarative animation of the reference to different
> (path) elements - there is often more than one way
> to get the intended effect - this is no reason to panic,
> just an indication for many options to get similar effects
> in an advanced language.
> If you don't need empty d elements, simply do not
> use them ;o)
>
> In SVG 1.1.2 and SVG tiny 1.2 there can be seen
> several efforts to avoid error messages, replacing them sometimes
> with 'disables rendering', sometimes with other meaningful
> behaviour, representing effectively a new feature - do you think,
> it is more useful to have an error message for such obvious
> things instead of the a display of the document?
> Of course, for some errors a message is more useful,
> but if the defined behaviour just describes, what one can
> expect, as here to render nothing, if d is empty, why not?
> Indeed there are already a few cases, where
> superfluous 'disables rendering' definitions prevent
> meaninful use cases, but here I cannot see an advantage
> in an error message or a more useful behaviour in case
> of an empty d.
>
> Olaf
Received on Friday, 11 May 2012 16:41:30 GMT

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