Re: Exploring new vocabularies for HTML

On Sat, Mar 29, 2008 at 4:17 PM, Henri Sivonen <hsivonen@iki.fi> wrote:

>
> On Mar 30, 2008, at 01:11, Henri Sivonen wrote:
> > Since SVG in MathML works fine in the #1 SVG-in-MathML browser
> > engine implementation (Gecko in Firefox 3), I think requiring the
> > <semantics><annotation-xml encoding="SVG1.1"> cruft around <svg> is
> > just silly and it would be better to make <svg> subtrees conforming
> > directly inside Presentation MathML.
>
>
> I meant to say that SVG in MathML works fine in Gecko without the
> <semantics><annotation-xml encoding="SVG1.1"> wrapper (so the wrapper
> is pointless).
>

I don't understand this argument.  It seems to be "since Gecko supports SVG
directly in MathML,  that proves there is no reason for a semantics
element".  Any implementation could support any random tag and make similar
statements, but then no other implementation would know what to do.
<semantics> provides a fallback for those implementations that don't
understand some possibly richer encoding than is possible in MathML.  This
is an important encapsulation for interoperability.

I'm not sure if you were being tongue in cheek when you said Gecko is the
"#1 SVG-in-MathML browser" -- it is the only such engine that I know of.  As
David pointed out, it is not legal MathML, although the standard tries to
provide an out for Firefox.  Pasting SVG in MathML into another application
or viewing the page in a different browser would cause an error, so it use
is likely to be a very bad idea unless you knew your target audience only
wanted to view the content in Firefox and never wanted to reuse it
elsewhere.

I believe that the use of SVG in MathML has been extremely limited.  Without
data, we can argue why, but since it isn't generated or imported by any of
the MathML editors, it is not too much of a leap to say that
interoperability is one of the leading reasons why it isn't used.  On the
other hand, semantics is used by many of the leading MathML authoring tools
(MathType, Mathematica, Maple, OpenOffice, ...).  You might not like
semantics, but based on current practice, many (most?) other applications
think it is useful.

Neil Soiffer
Senior Scientist
Design Science, Inc.
www.dessci.com
~ Makers of Equation Editor, MathType, MathPlayer and MathFlow ~