[cairo] Cairo and SVG

[Emmanuel Pacaud]

Le samedi 22 décembre 2007 à 14:21 -0800, Alan W. Irwin a écrit :
> On 2007-12-21 22:33+0100 Emmanuel Pacaud wrote:
> 
> > Hi,
> >
> > Le vendredi 21 décembre 2007 à 12:37 -0800, Alan W. Irwin a écrit :
> >> Note, it appears that SVG backend (I hope I am using the correct terminology
> >> here) is not nearly as well supported as the PS, PDF, PNG, and X backends.
> >
> > The SVG backend is officialy supported and passes the test suite. Please
> > report any bug you may have.
> 
> Further investigation done just now while attempting to prepare a proper bug
> report confirmed the lack of SVG text problem for the ImageMagick display
> programme on my current Debian testing platform.  Thus, this result confirms
> what I and other PLplot developers had seen previously on other platforms.
> However, I looked further and discovered both konqueror and iceweasel
> (firefox) for Debian testing show the text! So it appears now there has been
> a long-standing incompatibility between the ImageMagick display programme
> and cairo-derived SVG results.
> 
> If someone here can confirm that incompatibility using the SVG results
> produced directly by your test suite, than I leave it to you to figure out
> whether the issue is due to a bug in the "display" command or is that
> command being more careful about SVG standards than konqueror, iceweasel,
> and the SVG backend of libcairo?
> 
> I have just had a report that svgcairo results show no text with a Mac OS X
> SVG viewer so that is another example of a viewer that is either buggy or
> being extra careful about SVG standards. I will follow up with the reporter
> to find out exactly which viewer he used, but I doubt it was "display".

The text output of the cairo SVG backend uses the <symbol> element. And
it looks the imagemagick display command doesn't support it correctly. I
guess that's also the case for the OSX SVG viewer.

	Emmanuel.