Message-Id: <9211251151.AA00785@sc.zib-berlin.dbp.de>
Reply-To: Mailing list for the LaTeX3 project <LATEX-L@vm.urz.Uni-Heidelberg.de>
Date:         Wed, 25 Nov 92 12:46:49 +0100
From: David_Rhead@VME.CCC.NOTTINGHAM.AC.UK
Sender: Mailing list for the LaTeX3 project <LATEX-L@vm.urz.Uni-Heidelberg.de>
To: Multiple Recipients of <LATEX-L@vm.urz.Uni-Heidelberg.de>
Subject:      LaTeX 3 floating strategy: plates
Status: R


Although the LaTeX 2.09 mechanism for floats can be extended to support
things other than figures and tables, I think that plates which have to be
on a different type of paper (e.g., photographs or plots on special paper)
may need treating slightly differently:
1. Hugh Williamson describes a number of options for binding plates in.
   ("Methods of Book Design", 3rd edition, section 16.3).  It looks as though
   the rules for plate-floating are different from those for figure- and
   table-floating.  For example, if you have typeset pages 1-64 and pages
   65-128, my reading of Williamson is that the following may be good places
   for plates:
   - between pages 32 and 33 (for a single plate)
   - between pages 64 and 65 (for a group of plates).
2. With figures and tables, it may be desirable to let the end-user
   express a preference that "this table/figure should, if possible,
   be on the same 2-page spread as that table/figure".  However, with
   plates, the "same type of paper" constraint, would lead to different
   rules, e.g., "this plate needs another plate on its verso (but if we
   can't find another plate soon, the verso might be better left blank)"
   I.e., with figures and tables we need to think about 2-page spreads,
   but with plates we need to think about 2 pages back-to-back.
   [In unsophisticated production systems, as for theses, it may be
   inevitable that a plate has a blank reverse.  The only freedom
   would be to choose whether the picture appears verso or recto.]
3. The caption for a plate may appear on the adjacent typeset page,
   e.g., "Plate N (opposite) shows ... ".
4. Plates may be omitted from the page-numbering sequence for the typeset
   pages.  E.g., you might have "page 32, plate, page 33".  The "List
   of Plates" might then have to say "Plate N ... opposite page 32.
   Plate N+1 opposite page 33."
5. The user might like a choice between:
   (a) a pair of pages in the dvi file, as place-holders, to "represent" the
       recto/verso of a plate.  In the final document, the place-holders
       would be replaced by the real plate.
   (b) no place-holders (to save paper and laserprinting charges).

Fortunately, now that images can often be dealt with as PostScript and
treated as figures, plates may now be used less often than they used to be.
Nevertheless, they are still used to some extent, and it may be worth
bearing their idiosyncracies in mind when thinking about the floating
strategy for LaTeX 3.


David Rhead
JANET: d.rhead@uk.ac.nott.vme