Re: XeTeX 1.0 wishlist: \fontdimen's

On Oct 31, 2005, at 2:05 AM, Will Robertson wrote:

> Hi Jonathan,
>
> This is just a small issue, really, but if you're chasing down  
> little things for a 1.0 release then perhaps it qualifies.
>
> We've spoken before, I think, about how XeTeX isn't very good a  
> filling in \fontdimen values for non-tfm fonts. I also know that in  
> many cases they're not even relevant for fonts that are loaded. But  
> having them would be nice, and they can be ignored in non-Latin font.
>
> I'm especially interested in two: \fontdimen1 and \fontdimen5,  
> slant and ex-height. (I'm quite happy with \fontdimen6 = point  
> size.) For the first, this information might not be available to  
> you, but not setting it breaks LaTeX's ability to nest \emph{}s;  
> I'll be including a fix for this in the next version of fontspec,  
> but I can see it being useful in other circumstances also.
>
> If you can't get that info from a font, can it be set to a fixed  
> positive value if you know the font is italic?
>
> For the ex-height of a font, this is closely linked with not  
> knowing the height of the boxes passed to XeTeX. I'm not asking for  
> the latter (although I reiterate it'd be nice to have via a  
> character height-measuring primitive), but measuring the height of  
> an "x" (or maybe a different character, or maybe an average of a  
> few) when the font is loaded would be quite useful, in my opinion.
>
> Thanks for your hard work!
>
> Will

I second this -- if we can't have font-wide character information,  
then key pieces would be very useful indeed. Good point.

And, yes, thanks for XeTeX -- it has fundamentally transformed the  
TeX experience for me.

SGM