Re: [matplotlib-devel] mathtext in SVG backend

[John H. <jdh...@ac...>]

>>>>> "Jared" == Jared Wahlstrand <wah...@um...> writes:

    Jared> Hello, The attached patches implement mathtext for SVG. The
    Jared> output looks pretty good when viewed by Inkscape, but not
    Jared> the Adobe SVG viewer (it shows the wrong symbols and then
    Jared> moments later crashes Mozilla, at least on my system).  It
    Jared> hasn't been thoroughly tested for all of the possible
    Jared> symbols.

Hmm, this is strange and intriguing.  I notice that you do not embed
the fonts in your svg document, which is presumably why most viewers
can't handle it.  I confirmed that librsvg, which gqview uses, can't
render the fonts either.  The question is, why can Inkscape do it?  I
downloaded Inkscape and did a recursive grep through their src as well
as a find in the root of their src tree and found no references to
'computer modern' or cmex, etc....  Did you have to set some path in
inkscape to see your cm fonts, or did you put them in some standard
place?  Anyone have any ideas how inkscape manages to pull off this
trick?

    Jared> I had to add a math_parse_s_ft2font_svg() to mathtext.py,
    Jared> which basically does the same thing as
    Jared> math_parse_s_ft2font() but returns something different.  I
    Jared> tried to just modify the latter function to take a
    Jared> "usingSVG=True" argument and ran into all sorts of bizarre
    Jared> problems, probably associated with the caching, and gave
    Jared> up.  Perhaps someone can figure out how to do this more
    Jared> elegantly.

Probably the best way to do this is to subclass BakomaTrueTypeFonts
and override the just methods you need.

    Jared> John, are there any more features still missing from the
    Jared> SVG backend?

That almost does it.  I think we need an option to embed the fonts
directly into the svg document like we do for PS, because I think
viewers that have the cm* fonts built in will be the exception rather
than the rule.  Fernando Perez has some colleagues who are interested
in embedding clickable tags in svg, but I haven't heard much from
them.

But overall SVG is in fine shape.

Many thanks!
JDH