On 11-6-2012 17:43, Frank Mittelbach wrote:
Hans,
my fluency in the linebreak algorithm is a little bit rusty. Are you saying that there are other points and stuff in that space that is not updated or more on the page builder side of the house?
More in the pagebuilder area where we have this insert stuff (which for that reason I mostly left for the future). In your case setting the prevdepth and prevgraf is indeed needed. Actually, you need: \def\partest {% \directlua {% function hpackparagraph (head) local h = node.hpack(head) tex.nest[tex.nest.level].prevgraf = 1 tex.nest[tex.nest.level].prevdepth = h.depth return h end callback.register("linebreak_filter", hpackparagraph) }% \par } btw, Internally the linebreaker is somewhat complicated by the fact that hz and protrusion play a role. I have a (lua) parbuilder prototype that gets rid of a lot of that code but Harmut needs time to implement a few things in the backend (will happen later this year) and that in turn will make the parbuilder cleaner. We also want systematic usage of left/rightskip nodes in broken lines so that we can have a more predictable model of a broken line.
Or asked differently is there more that needs updating to make my little example work, and if so could that be already done through a workaround like I did with
tex.nest[tex.nest.ptr].tail = node.tail(head)
or would it absolutely need fixes in the program itself?
Sort of. The returned -1 is now a signal that prevdepth has not been set and that is not something deliberate. However, the fact that you need to set prevdepth and prefgraf (maybe more) explicitly gives the possibility to manipulate those depth and graf parameters. So, in any code that uses the callback one needs to take care of these variables anyway. Hans p.s I remember that there has been some fixes to lastnode(type) so it might as well that at that time some buglet crept in. ----------------------------------------------------------------- Hans Hagen | PRAGMA ADE Ridderstraat 27 | 8061 GH Hasselt | The Netherlands tel: 038 477 53 69 | voip: 087 875 68 74 | www.pragma-ade.com | www.pragma-pod.nl -----------------------------------------------------------------