[XeTeX] additional beginL endL nodes in math

[Khaled Hosny]

On Fri, Apr 17, 2015 at 03:31:33PM +0100, David Carlisle wrote:
> On 17 April 2015 at 15:26, Philip Taylor <P.Taylor at rhul.ac.uk> wrote:
> >
> >
> > David Carlisle wrote:
> >
> >> possibly but in the interests of keeping divergence of tex-related
> >> engines to a minimum
> >> as a first approach (if different approaches were being considered)
> >> I'd look to what luatex
> >> is doing, where colour and directionality can be specified without
> >> introducing new nodes
> >> colour being an attribute of the font for example.
> >
> > Colour is already an attribute of the font in XeTeX, is it not ?
> > The syntax certainly suggests that it is :
> >
> >         \font \thisfont = "Tw Cen MT Condensed":color=968A4D scaled 955
> >
> > for example.
> >
> > ** Phil.
> >
> 
> 
> yes but the latex color package doesn't know that (who wrote that
> package, anyway)

And you can’t use it for all cases, e.g. rules will no be colored, nor
it can be used to set background color. LuaTeX attributes are generic
and can be used anywhere, and some packages use to to pass around color
information, but without the ability to process nodes using Lua, its use
will be very limited.

Regards,
Khaled