<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
</head>
<body text="#000000" bgcolor="#FFFFFF">
<div class="moz-cite-prefix">Barbara Beeton wrote:<br>
<br>
</div>
<blockquote type="cite"
cite="mid:alpine.LRH.2.21.2006251654490.26663@tug.org">An even
more rigid model followed by traditional typesetting is "grid
<br>
typesetting", in which *all* baselines line up on facing pages.
As has
<br>
often been noted, this is *not* followed by, and is not easy to
obtain
<br>
with TeX, especially in the presence of math displays.<br>
</blockquote>
<br>
As Barbara is (in my experience) never wrong, what follows is in no
sense a correction but rather an amplification. One <i>can</i>
typeset spreads on a grid, but TeX lacks (IMHO) one vital element
that would much simplify this process, to wit a box with two
reference points. In the absence thereof one has to work around the
problem (an early solution made use of \pseudoboxes) but I think
that were I to tackle the problem again today I would take advantage
of the fact that leaders <i>behave</i> like a skip but can actually
include real typeset material.<br>
<br>
To re-cycle my example of earlier this afternoon, consider the
following :<br>
<br>
<blockquote type="cite">% !TeX Program=XeTeX
<p style="-qt-paragraph-type:empty; margin-top:0px;
margin-bottom:0px; margin-left:0px; margin-right:0px;
-qt-block-indent:0; text-indent:0px; line-height:100%;"><br>
</p>
<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px;
margin-right:0px; -qt-block-indent:0; text-indent:0px;
line-height:100%;">\parskip = 0 pt</p>
<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px;
margin-right:0px; -qt-block-indent:0; text-indent:0px;
line-height:100%;">\parindent = 0 pt</p>
<p style="-qt-paragraph-type:empty; margin-top:0px;
margin-bottom:0px; margin-left:0px; margin-right:0px;
-qt-block-indent:0; text-indent:0px; line-height:100%;"><br>
</p>
<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px;
margin-right:0px; -qt-block-indent:0; text-indent:0px;
line-height:100%;">\font \gfont = cmr10 scaled 5000</p>
<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px;
margin-right:0px; -qt-block-indent:0; text-indent:0px;
line-height:100%;">\def \good {\lower 3,5 ex \hbox {\gfont g}ood
}</p>
<p style="-qt-paragraph-type:empty; margin-top:0px;
margin-bottom:0px; margin-left:0px; margin-right:0px;
-qt-block-indent:0; text-indent:0px; line-height:100%;"><br>
</p>
<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px;
margin-right:0px; -qt-block-indent:0; text-indent:0px;
line-height:100%;">\baselineskip = 5mm</p>
<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px;
margin-right:0px; -qt-block-indent:0; text-indent:0px;
line-height:100%;">\lineskip = 0 pt</p>
<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px;
margin-right:0px; -qt-block-indent:0; text-indent:0px;
line-height:100%;">\lineskiplimit = -\maxdimen</p>
<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px;
margin-right:0px; -qt-block-indent:0; text-indent:0px;
line-height:100%;">\abovedisplayskip = 0 pt</p>
<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px;
margin-right:0px; -qt-block-indent:0; text-indent:0px;
line-height:100%;">\abovedisplayshortskip = 0 pt</p>
<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px;
margin-right:0px; -qt-block-indent:0; text-indent:0px;
line-height:100%;">\belowdisplayskip = 0 pt</p>
<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px;
margin-right:0px; -qt-block-indent:0; text-indent:0px;
line-height:100%;">\belowdisplayshortskip = 0 pt</p>
<p style="-qt-paragraph-type:empty; margin-top:0px;
margin-bottom:0px; margin-left:0px; margin-right:0px;
-qt-block-indent:0; text-indent:0px; line-height:100%;"><br>
</p>
<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px;
margin-right:0px; -qt-block-indent:0; text-indent:0px;
line-height:100%;">\topglue 12.2mm</p>
<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px;
margin-right:0px; -qt-block-indent:0; text-indent:0px;
line-height:100%;">\obeylines</p>
<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px;
margin-right:0px; -qt-block-indent:0; text-indent:0px;
line-height:100%;">The Leith police dismisseth us, for we
sufficeth them.</p>
<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px;
margin-right:0px; -qt-block-indent:0; text-indent:0px;
line-height:100%;">The quick brown fox jumps right over the lazy
dog's back.</p>
<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px;
margin-right:0px; -qt-block-indent:0; text-indent:0px;
line-height:100%;">\leaders \vbox {$$x^2 = y^2 + z^2$$}\vskip
2\baselineskip</p>
<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px;
margin-right:0px; -qt-block-indent:0; text-indent:0px;
line-height:100%;">Now is the time for all \good men to come to
the aid of the party.</p>
<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px;
margin-right:0px; -qt-block-indent:0; text-indent:0px;
line-height:100%;">Here endeth the first lesson.</p>
<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px;
margin-right:0px; -qt-block-indent:0; text-indent:0px;
line-height:100%;">\eject</p>
<p style="-qt-paragraph-type:empty; margin-top:0px;
margin-bottom:0px; margin-left:0px; margin-right:0px;
-qt-block-indent:0; text-indent:0px; line-height:100%;"><br>
</p>
<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px;
margin-right:0px; -qt-block-indent:0; text-indent:0px;
line-height:100%;">\end</p>
</blockquote>
<br>
View the output in Adobe Acrobat with the grid visible, grid
separation 5mm, sub-divisions 10, and you will see that baseline
registration is maintained perfectly across the display maths.<br>
<br>
<i>Philip Taylor</i><i> </i>[E&OE — the first time I have tried
this technique.]<br>
</body>
</html>