On Mon, 2002-12-09 at 01:00, Arved Sandstrom wrote: > I actually helped push for this last year - the notion of separate layout > managers. I was strongly influenced by the mess that FOP code had become at > the time, and really thought that layout should be taken out of the FOs > themselves; that the FO's, in a sense, were (or should be) just value > objects. > > I worked on an xslfo-proc prototype (in Perl) for months earlier this year. > I started out with the layout manager idea. It became increasingly clear to > me that there was in fact a natural 1-1 correspondence between managers and > FOs. I had a prototype, incidentally, which properly handled > reference-orientation in all regions, and even took RO down to > block-containers, something which no implementation (not FOP, not XEP, not > XSLFormatter, not XFC) has correctly done. Unless Epic handles RO correctly, > which I don't know. > > It's also interesting, Joerg, that you should mention a "hard to understand" > layout manager class hierarchy...this is also what inevitably developed in > my prototype. So at some point (and I think there are comments and emails to > support this) I eventually came back to the thought that there is nothing > wrong with individual FOs being able to do their own layout. Which is > actually the existing "maintenance stream" FOP model.
I still believe that it is useful to have the layout managers separate from the fo tree. There are a number of reasons that come to mind. It is possible to independantly change layout managers. Certain fo's aren't directly in the same hierarchy: markers, undefined table columns, table cells under table body. Then there are things like floats and footnotes that can gain from this. > I'll have some more to say later....these are immediate comments. I am just > struck by the fact that it is now December 2002 and we are not where we want > to be, not even close, which is providing an open-source Extended > conformance XSL processor to the hungry, huddled and poor. --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, email: [EMAIL PROTECTED]
