Re: specification for Mozilla's SVG in OpenType proposal

Hi,

A couple of weeks ago, I played around trying to create a new font to
use with Mozilla's SVG in OpenType implementation in the latest Firefox
and have some comments the proposals.

I found the experience a bit frustrating as the tools available are
rather limited. I used a combination of Inkscape (to draw the glyphs),
FontForge (to create an "empty font" to hold the glyphs), and some
python scripts I got earlier from Cameron (to insert the SVG into the
font). Clearly, once the specification is finished, the tool chain will
get fixed but there are somethings that might make it easier to create
such tool chains.

The first thing I discovered was that the format for the glyphs doesn't
follow the SVG 1.1 spec. Instead of using <glyph>, two new attributes
have been defined so that any element can be used as a glyph. This makes
it more difficult to use existing SVG glyphs as a source for SVG in
OpenType and at the moment, in creating new SVG glyphs for use in OT. At
first I thought I could use Inkscape to create the glyphs (Inkscape has
the ability to create but not use SVG fonts), then use FontForge to
create a "normal" OpenType font with the glyphs, and then insert the SVG
table using the Python scripts. Since the SVG in OT glyphs are not
defined with <glyph> it meant I had to create duplicates of each glyph
(inverting the y-axis on one of them). My question is, why not just use
<glyph>? One could create an SVG font, with a file to test it and then
simply insert the <glyph> elements into the OpenType without having to
manipulate it excessively. There are cases where one might want both a
"stand-alone" SVG font and an SVG in OpenType font; having the same
glyph format would make that easier.

Another weakness I found in the current proposal is the inability to
pass more than one or two color attributes (color in the case of HTML,
fill and stroke colors in the case of SVG) into the glyphs.

One thing that became obvious to me, is that the whole process of
creating an SVG in OpenType font has a tremendous amount of overhead. It
requires font editing software with the knowledge of how to use it. This
is not something that a typical graphic designer is likely to have. We
talk about the desire that SVG should be "hand-editable." This is about
as far from that as possible. The time invested in creating an SVG font
may be worth it when creating reusable fonts but is definitely not
something one likely would do to create a "one-off" title or even a
handful of headings. An alternative method is still needed for providing
accessibility in these cases.

I agree with Leonard that we need to pay attention to non-web uses of
SVG in OT fonts.

Tav

Received on Monday, 4 February 2013 11:46:25 UTC