# [XeTeX] \predisplaysize in XeTeX

Bruno Voisin bvoisin at mac.com
Thu Jun 17 09:51:00 CEST 2004

Le 17 juin 04, à 00:23, Bruno Voisin a écrit :

> Everything's right. Now replaces CMR by Trebuchet:
>
> 	\font\tenrm="Trebuchet MS" at 10pt
> 	\font\tenit="Trebuchet MS Italic" at 10pt
> 	\font\tenbf="Trebuchet MS Bold" at 10pt
> 	\font\tenbi="Trebuchet MS Bold Italic" at 10pt
> 	\rm
> 	One form of the solution of the wave equation (9) is the inverse
> Fourier transform
> 	$$> \zeta({\bf r},t) = {\rm e}^{-{\rm i}\sigma t} > \int\!\!\!\int\!\!\!\int {F({\bf k})\over B({\bf k},\sigma)} > {\rm e}^{{\rm i}(kx+ly+mz)}\,{\rm d}k{\rm d}l{\rm d}m, >$$
> 	\bye
>
> The space between the displayed equation and the preceding line is set
> to practically zero, which seems to indicate that
> \abovedisplayshortskip is used instead of \abovedisplayskip.

Something I forgot: if a single character from a non-AAT font is
inserted in the line immediately preceding the displayed equation, for
example:

\font\tenrm="Trebuchet MS" at 10pt
\font\tenit="Trebuchet MS Italic" at 10pt
\font\tenbf="Trebuchet MS Bold" at 10pt
\font\tenbi="Trebuchet MS Bold Italic" at 10pt
\rm
One form of the {\sevenrm solution} of the wave equation (9) is the
inverse Fourier transform
$$\zeta({\bf r},t) = {\rm e}^{-{\rm i}\sigma t} \int\!\!\!\int\!\!\!\int {F({\bf k})\over B({\bf k},\sigma)} {\rm e}^{{\rm i}(kx+ly+mz)}\,{\rm d}k{\rm d}l{\rm d}m,$$
\bye

then all of a sudden the \predisplaysize is set correctly, which leads
me to assume that for AAT fonts its calculation is incorrect.

Hope this helps,

Bruno