RE: altglyph

responses below.

> -----Original Message-----
> From: Jon Ferraiolo [mailto:jferraio@Adobe.COM]
> Sent: Wednesday, September 22, 1999 1:51 PM
> To: Paul Topping
> Cc: 'www-svg@w3.org'
> Subject: Re: altglyph
> 
> 
> Hi Paul,
> 
> At 09:08 AM 9/22/99 -0700, Paul Topping wrote:
> >Hello,
> >
> >I've been reading Section 12.6, "Ligatures and alternate 
> glyphs", of the SVG
> >spec where the "altglyph" attribute is described. I'm a 
> little confused as
> >to the details of altglyph.
> 
> In the August 12 spec, 'altglyph' is a CSS property, not an attribute.
> Since it is a property, it can be specified as part of an 
> external style
> sheet, as part of an internal style sheet via a <style> 
> element, or within
> an inline style via the 'style=' attribute, which is available on most
> elements in SVG.

I was unable to find any mention of "altglyph" in any of the CSS docs. Could
you point me at some documentation on it?

> The international working group has a strong interest in 
> 'altglyph' as it
> has considerable utility in a variety of scenarios, including 
> Japanese.
> Also, 'altglyph' has applicability to other XML grammars such 
> as XHTML.
> They have given feedback to the SVG working group that 
> questions whether
> CSS properties are the best approach for 'altglyph'. There is 
> a chance that
> 'altglyph' could change from a property to an element or an attribute.

I think "altglyph" has applicability to math rendering as well. If we render
MathML by converting it into CSS (possibly with new math-related CSS
elements) and HTML, we will rely on plain text for rendering individual math
characters. Regardless of how many math characters are in Unicode (now or in
the future), we will be dealing with a lack of font and character knowledge
in browsers for some time to come. It seems like "altglyph" might be needed,
at least in the interim, to get the desired character in the desired math
font to appear on the page.

> >- It is not clear to me what element this is an attribute 
> of. Is it the
> >"text" element? I couldn't find altglyph mentioned in the DTD.
> 
> With the August 12 spec, because 'altglyph' is a property, it can be
> specified in all of the ways I have described earlier. 
> However, it only
> makes sense to specify it on a "text" element.

I know this isn't your responsibility, but do you know if any of the SVG
prototype renderers deal with "altglyph" right now?

> >- The description under the "Unicode" value leads one to 
> believe that it
> >describes a string of characters, whereas that of the 
> "gyphid" value sounds
> >like it describes a single character.
> 
> The original idea was the only one Unicode value would be 
> provided, but
> again this is subject to change in response to Last Call feedback.
> 
> >
> >Can anyone shed any light on this attribute?
> >
> >Paul Topping
> >pault@mathtype.com
> >Design Science, Inc. 
> 
> Jon Ferraiolo
> SVG editor
> Adobe Systems Incorporated
>

Received on Thursday, 23 September 1999 14:42:20 UTC