Embedded fonts in SVG

Has anyone looked into embedding fonts in SVG files? That might alleviate some of the installation problems that were recently mentioned on the matplotlib-users list.

The relevant spec:

http://www.w3.org/TR/SVG11/fonts.html

If there are no plans under way, I may have a crack at it, since I'm sort of on an "embedding fonts" kick lately anyway... :wink:

Cheers,
Mike

It's definitely come up before. Paul Barret may have had a look at
it. I'm not sure why we ended up not doing it. You can search the
archives if you are interested. If it isn't too hard, and major SVG
renderers support it, it seems like a great idea.

JDH

路路路

On 7/10/07, Michael Droettboom <mdroe@...31...> wrote:

Has anyone looked into embedding fonts in SVG files? That might
alleviate some of the installation problems that were recently mentioned
on the matplotlib-users list.

The relevant spec:

http://www.w3.org/TR/SVG11/fonts.html

If there are no plans under way, I may have a crack at it, since I'm
sort of on an "embedding fonts" kick lately anyway... :wink:

John Hunter wrote:

Has anyone looked into embedding fonts in SVG files?

It's definitely come up before. Paul Barret may have had a look at
it. I'm not sure why we ended up not doing it. You can search the
archives if you are interested. If it isn't too hard, and major SVG
renderers support it, it seems like a great idea.

"major SVG renderers" support seems to be the issue at first glance. None of the big open source options -- Firefox, inkscape, rsvg -- seem to support it. Please let me know if I'm missing something. Firefox has even pushed SVG fonts off of the Firefox 3 timeline:

http://weblogs.mozillazine.org/tor/archives/2007/03/svg_priorities_in_firefox_3.html

Until there's something readily available to test with, there's probably not much point.

Cheers,
Mike

路路路

On 7/10/07, Michael Droettboom <mdroe@...31...> wrote:

"major SVG renderers" support seems to be the issue at first glance.
None of the big open source options -- Firefox, inkscape, rsvg -- seem
to support it.

That's my understanding as well.

Until there's something readily available to test with, there's probably
not much point.

It's a classic chicken-and-egg. I know the cairo-svg maintainer is
hoping to add SVGFont stuff to cairo's SVG output to try to boostrap
past this problem.

-Carl

路路路

On Tue, 10 Jul 2007 13:43:49 -0400, Michael Droettboom wrote:

Actually, it just occurred to me that you could use 'defs' and 'use' to define characters as paths and reuse them. And that's something that works today in virtually any SVG renderer.

It totally blitzes the logical representation of the text (i.e. searching and copying as text etc.), but if it was only done for math text, then that's probably not a big deal. IMHO, math text is where matching the exact font is most important, where a reasonable substitute is often not installed, and where searching doesn't make a lot of sense. In any case, editing the SVG in something like Inkscape will be harder, since the text has become raw paths.

Thanks to ft2font, it was fairly easy to get outlines of math characters embedded in the SVG file. I've put up an example mathtext_demo.py SVG here:

聽聽聽聽ftp://ftp.stsci.edu/tmp/mdroe/mathtext_demo.svg

I'll commit this code once it's cleaned up and better tested etc. if it's agreed this is something we want to do. I think in any case this should be optional -- it gives the file some portability at the expense of editability.

Cheers,
Mike

Carl Worth wrote:

路路路

On Tue, 10 Jul 2007 13:43:49 -0400, Michael Droettboom wrote:
聽聽

"major SVG renderers" support seems to be the issue at first glance.
None of the big open source options -- Firefox, inkscape, rsvg -- seem
to support it.
聽聽聽聽
That's my understanding as well.

Until there's something readily available to test with, there's probably
not much point.
聽聽聽聽
It's a classic chicken-and-egg. I know the cairo-svg maintainer is
hoping to add SVGFont stuff to cairo's SVG output to try to boostrap
past this problem.

I've tested this approach with Firefox 2.0 and rsvg 2.16. The text alignment is actually much better since the text layout is fully under the control of matplotlib. This has been checked into SVN, and can be used by setting the rcparam "svg.embed_char_paths" to True.

The following are my usual "size benchmarks" (that I used for PS and PDF as well):

without character paths -> with character paths
fonts_demo_kw.py: 10314 -> 69256
mathtext_demo.py: 10606 -> 37896
unicode_demo.py: 7677 -> 43473
over all demos in backend_driver.py: 17,722,815 -> 18,789,999

Cheers,
Mike

Michael Droettboom wrote:

路路路

Actually, it just occurred to me that you could use 'defs' and 'use' to define characters as paths and reuse them. And that's something that works today in virtually any SVG renderer.

It totally blitzes the logical representation of the text (i.e. searching and copying as text etc.), but if it was only done for math text, then that's probably not a big deal. IMHO, math text is where matching the exact font is most important, where a reasonable substitute is often not installed, and where searching doesn't make a lot of sense. In any case, editing the SVG in something like Inkscape will be harder, since the text has become raw paths.

Thanks to ft2font, it was fairly easy to get outlines of math characters embedded in the SVG file. I've put up an example mathtext_demo.py SVG here:

聽聽聽聽ftp://ftp.stsci.edu/tmp/mdroe/mathtext_demo.svg

I'll commit this code once it's cleaned up and better tested etc. if it's agreed this is something we want to do. I think in any case this should be optional -- it gives the file some portability at the expense of editability.

Cheers,
Mike

Carl Worth wrote:
聽聽

On Tue, 10 Jul 2007 13:43:49 -0400, Michael Droettboom wrote:
聽聽

"major SVG renderers" support seems to be the issue at first glance.
None of the big open source options -- Firefox, inkscape, rsvg -- seem
to support it.
聽聽聽聽

That's my understanding as well.

Until there's something readily available to test with, there's probably
not much point.
聽聽聽聽

It's a classic chicken-and-egg. I know the cairo-svg maintainer is
hoping to add SVGFont stuff to cairo's SVG output to try to boostrap
past this problem.
聽聽
-------------------------------------------------------------------------
This SF.net email is sponsored by DB2 Express
Download DB2 Express C - the FREE version of DB2 express and take
control of your XML. No limits. Just data. Click to get it now.
http://sourceforge.net/powerbar/db2/
_______________________________________________
Matplotlib-devel mailing list
Matplotlib-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/matplotlib-devel