[xsl] XSL:FO approach for facing-page translation

[Martin Holmes <mholmes@xxxxxxx>]

Hi all,

I have an interesting problem to solve with an edition of a source text 
which has an accompanying translation.

The text is in paragraphs, with each paragraph in the original matching 
one in the translation. In XHTML, I'm easily able to render the two 
texts in a borderless table, with a row for each paragraph, giving a 
nice readable parallel-text view.

I need to do something similar in PDF, using XSL:FO. The ideal would be 
to have the original text on the verso page, with the equivalent 
translation on the facing recto. But I can't figure out a practical 
approach to this. For one thing, I don't see how I can render individual 
pages from one text and then the other text in alternating fashion, and 
for another, I don't see any way to keep the two texts in sync. I can 
disallow page-breaks within paragraphs, but I'd have to be 
extraordinarily lucky for the two texts to end up breaking at the same 
points every time; it would just take one slightly-shorter paragraph on 
one side to put them out of sync by a paragraph. Such a strategy would 
also be rather a paper-waster, because many pages would have a lot of 
blank space at the bottom.

Has anyone every done anything like this, and if so, do you have any 
advice? I can imagine that it might be done in a horribly manual fashion 
by trial and error, working page-by-page, but I really don't want to get 
into that. I'm happy to pre-process the text multiple times before it 
goes to the XSL:FO stage., Perhaps there are ways to measure (for 
instance) how much space a paragraph will take, and then adjust 
page-margins or spacing by small increments to preserve alignment 
between the two texts, but I haven't seen examples of such an approach.

All advice much appreciated.

Cheers,
Martin