These are notes about the page layout of the manuscript Proof and Counterexample. You can see what I'm talking about if you download the pdf file with hyperlinks for viewing on a screen or a two-up pdf file for printing.
The draft I'm working with is set at 12pt on A4 paper. (This means that it will still be legible when you print the document 2up.) It's important, for easy legibility, for a line to not contain too many words. This means, in my case, that a line length should be around 120mm, and not much longer. This leaves an awfully big margin. I decided to make the typeblock (that's the rectangle of text on the page) have the ratio 2x1 (it's twice as high as it is long). The typeblock in my case is 122.5mm wide and twice that (245mm) high.
Then you need to select the top & bottom margins, and the inner & outer margins. I've decided for the manuscript to be pretty close to a possible design for the book, so it's designed to have different inner & outer margins (like a book has), and for these to alternate from page to page. Instead of having large margins on the left and on the right, It's possible then to have really large outer margins, and narrower inner margins. In the manuscript, the outer margins are four times the size of the inner margins. This gives us a really large space outside the outer margins (over 56mm), in which we can fit marginal notes. For upper/lower margins, I settled on a lower margin twice the size of the upper margin, and the page looks decent.
All of this can be achieved with the following simple code, provided that you use the (memoir document class).
\settrimmedsize{\stockheight}{\stockwidth}{*}
\settypeblocksize{*}{122.5mm}{2}
\setlrmargins{*}{*}{4}
\setulmargins{*}{*}{2}
\setmarginnotes{4.375mm}{52.5mm}{12mm}Isn't that wonderfully simple? In the declarations (like \setlrmargins{*}{*}{4} you are in effect saying, “set the outer margin to be four times the inner margin — and figure out what values the inner margin and outer margin are. You've got enough information to do that.” This is exactly the right way to use computers!)
This wonderfully roomy margin space has another nice side effect, beyond room for the author and the reader to scribble marginal notes. It is also a space for displayed mathematical text to creep into if necessary. You'll notice that a large proof or table or other item will sometimes extend into the outer margin if the space is needed. I think this is a useful effect. Here's how you can do it. You can define a widematter environment as follows. (This is taken out of my main pc.tex file.)
%% widematter environment
%%
%% intended for figures or other display material that exceeds
%% the width of the standard text block.
%% This will fit the material inside the textblock+marginal notes area,
%% flush right on an even page and flush left on an odd page.
%%
%%
\newlength{\extrawidth}
\setlength{\extrawidth}{\marginparsep}
\addtolength{\extrawidth}{\marginparwidth}
\newenvironment{widematter}
{\begin{adjustwidth*}{0mm}{-\extrawidth}
\strictpagechecktrue\checkoddpage
\ifoddpage\begin{flushleft}\else\begin{flushright}\fi}
{\ifoddpage\end{flushleft}
\else\end{flushright}\fi
\end{adjustwidth*}}First, we set the length \extrawidth to be the width of the gap between the main body of text and the margin paragraph area, and add to that the width of the margin paragraph area itself.
The adjustwidth* environment (from the memoir class) adds nothing to the inner margin, and \extrawidth to the outer margin. This might be enough, but if your material is only a little bit wider than the textblock, the ideal would be (it seems to me) for it to extend out of the textblock just as much as is needed. The trick now is to check if you're on an even or an odd page. If you're on an odd page, you're on the right of the page spread, and the outer margin is on the right. So, you typeset the material flushleft. If you're not on an odd page, you're on an even page, so you typeset the material flushright.
The \strictpagechecktrue call is also from memoir, and it makes page checking quite robust. (At least, once you LaTeX your document twice. It writes a bit of information in the aux file once its typest the material, which it reads the next time around when it's preparing it.)
The only cases where it doesn't work for me is when the widematter environment is just at the top of a new page. In this case, it seems that the check happens at the end of the previous page, and the prediction of which way to set the diagram is off. I haven't estabilished a way to avoid this in general, but in the cases where it has hurt me, typesetting a \vphantom{.} before the widematter environment seems to do the trick. You make room for the invisible character of no width and the height of a period, this brings you to the next page, where you then check your page location, and all works fine. However, if you do this on every widematter environment, you add too much space before the material you're typesetting. So I don't do that in every case. If anyone has a better way of handling this, I'd love to know.
(Please add any comments, advice, or suggestions for improvement here, both on the widematter environment I'm using, and the general topic of the page layout of Proof and Counterexample.)