Hi, On Mon, Aug 10, 2009 at 4:33 PM, Thomas Mortagne <[email protected]>wrote:
> On Mon, Aug 10, 2009 at 16:14, Sergiu Dumitriu<[email protected]> wrote: > > Hello Community, > > > > I have committed today the first implementation of a new XWiki feature: > > rendering mathematical equations into images. It is available as a > > standalone component, and as a syntax 2.0 macro. > > > > > > > > About the functionality. > > > > Equations are written in the TeX/LaTeX syntax, which is pretty simple, > > and seems to be the syntax of choice for mathematical equations in other > > wikis, too. The macro can distinguish between inline and block equations > > and render them accordingly. The output can be either PNG (the default > > one), GIF or JPEG. While PNG is definitely the best, I kept the other > > two in case somebody really wants to use ancient browsers that only > > understand GIF. > > > > Q: Should I leave just PNG as the output format? > I think keeping PNG as the default format is fine too, most browsers accept it without complaint. > > > > > Another feature is that the font size can be specified, in order to > > render larger or smaller equations. All the font size commands from > > LaTeX (from \tiny to \Huge) have an equivalent. I renamed them to a more > > easy to understand name (also because the configuration is case > > insensitive, so there's no difference between large and LARGE). > > > > By default images are generated so that the font looks relatively OK > > with the default XWiki skin on a 72 or 96 DPI display. They might look > > disproportionate with a different DPI, or with a different default font > > size. > > > > Q: Is the default DPI setting OK? > > > > > > > > Second, a few technical details: > > > > The standalone component is located in > > platform/core/xwiki-equation-rendering. I don't know if the name is the > > I don't like this name either "rendering" is too much linked to the > rendering module now and this could be used by anyone, not only the > equation macro. > > It's also true that xwiki-equation is not clear enough but you could > maybe find something else. xwiki-equation-displayer maybe ? > > > > best (Vincent complained). On one hand, this describes better what the > > component does: it renders equations. On the other hand, it might cause > > confusion with the xwiki-rendering system. > > > > The component currently has three implementations: > > > > - a native one, which relies on the latex system being present. It gives > > the best results, from a graphical point of view, but requires the > > presence of external programs, and involves a slight overhead for > > starting new processes and for working with the disk. Currently it might > > have some security problems, I'll have to see if opening input and > > output files from TeX is a problem, or how to disable this. Any help > > from someone who know more about TeX? > > > > Q: Does anybody know of any security issues with running latex, dvips or > > convert? Especially with the \openin and \openout commands? > > > > - one which uses MathTran as a remote service through HTTP requests. It > > gives results as good as the native one, enhanced with some metadata, > > and depending on the configuration of the server, it might have better > > performance than the native one. The disadvantage is that it relies > > heavily on a remote server. Note that MathTran is free software, and can > > be installed locally on the same or a neighboring server. Oh, another > > minor problem is that it uses a variant of the TeX syntax, not LaTeX. > > > > - one which uses SnuggleTeX and JEuclid to transform LaTeX into MathML, > > and then render it into images. The results are not as eye-pleasing as > > those obtained from LaTeX, but it is a self-contained solution, with no > > external dependencies. > > > > SnuggleTeX uses the liberal 3-clause BSD license, JEuclid uses the > > Apache v2 license, so both can be deployed. Together, they weight in at > > 730k, so it's not a big impact. The other two implementations are not > > contaminated by the licenses of the underlying system, so there's no > > license conflict. > > > > Q: Should either one be removed? > > > > Q: Do you know of any other (better) alternative? > > > > By default the native renderer is used, since it gives the best results > > and doesn't depend on an external service. SnuggleTeX is configured as a > > backup (safe) renderer which kicks in when the default one isn't working > > (missing tex subsystem, or communication error with the remote server). > > > > Q: Is this setup OK as the default one? (native by default, snuggletex > > as fallback). > > > > The generated images are stored in a cache (using the cache component), > > for improved performance. This new cache might increase the memory > > requirements, but fortunately it is easy to configure. > > > > The rendering macro is located in > > > platform/core/xwiki-rendering/xwiki-renderig-macros/xwiki-rendering-macro-equation, > > and the macro can be used with > > > > {{equation}}\sum_{i=0}^{\infty}{{/equation}}. > > > > Q: Is the macro name appropriate? Do you know of a better one? > > > > > I think "equation" is fine. > > > > > Future work: > > - make sure that there are no security issues with the Native backend > > - add support for MathML display for the clients that understand it > > - improve the alignment of images (especially for the Native backend), > > as right now they are a bit raised above the text baseline > > > > > > Many thanks to Guillaume Legris who provided the starting point for this > > component. > Good work, thanks Guillaume & Sergiu ! Guillaume > > > -- > > Sergiu Dumitriu > > http://purl.org/net/sergiu/ > > _______________________________________________ > > users mailing list > > [email protected] > > http://lists.xwiki.org/mailman/listinfo/users > > > > > > -- > Thomas Mortagne > _______________________________________________ > users mailing list > [email protected] > http://lists.xwiki.org/mailman/listinfo/users > -- Guillaume Lerouge Product Manager - XWiki Skype: wikibc Twitter: glerouge http://guillaumelerouge.com/ _______________________________________________ users mailing list [email protected] http://lists.xwiki.org/mailman/listinfo/users
