The typesetting engine, LATEX, is structure-oriented — that is, an author focuses on content and meaning, not presentation. When composing print output, the engine applies presentation rules derived from the document’s structure. This separation of content from presentation means printed pages are set out in a consistent manner, no matter how many different authors are involved.
It is this separation which enables us to generate web and print output from the same source. However, PmWiki also provides Wiki Styles, enabling authors to control the presentation of individual content elements, supplementing or over-riding any rules which a site administrator may have specified in the site’s web style sheet. There are 3 kinds of styling:
While wiki markup elements are media-neutral and can be readily transformed to web or print, styles are web-oriented and hence can present a problem for the print channel. Specifically, we have to transform css-based web page styles into structure-based print page elements. Most of the time, authors don’t need to worry about this — Wikipublisher takes care of it.
To do this, it makes “reasonable assumptions”:
inline styles are mostly honoured
authors need to use inline styles with some caution — what looks good on the web may not look good in print, and vice versa
block styles are usually honoured, but may be ignored
in general, it honours structural instructions (float this image right) but ignores formatting instructions (centre this heading)
division styles are treated case-by-case
these are usually interpreted as print side-bars and float to the top or bottom of the page; this is a problem if the division is bigger than a page
This area will continue to evolve and improve. At the moment, it’s fair to say that the more authors use markup, the less they have to worry about what the print output looks like. The more they use styles, the more they have to check that the print effect is suitable.
To be continued…