Hello list, The solution shown here no longer works with recent beta (indeed, it probably ceased to work some time ago). How should it be corrected?
Best Piotr 2010-10-24 0:14 GMT+02:00 Aditya Mahajan <adit...@umich.edu>: > On Sat, 23 Oct 2010, Herbert Voss wrote: > >> It is a hard job to understand how all works ... > > > I agree. That chapter is confusing if you do not know already how the > mechanism > works. > >> I tried to create the first example of the >> documentation "Page 257 Anchors and layers", >> but failed with mkii and iv. The page is created, >> but without the graphical elements. Not using >> \startbuffer--\stopbuffer makes no difference. > > > You are simply setting the positions. You also need to tell ConTeXt to do > something with the positions. > > 1. First define a position graphic that does something with the anchors that > it is passed. > > \startMPpositiongraphic{mypos:arrow} > pair c[] ; > initialize_box(\MPpos{\MPvar{self}}); > c[1] := cxy ; > initialize_box(\MPpos{\MPvar{to}}); > c[2] := cxy ; > drawarrow c[1] -- c[2] withpen pencircle scaled 2bp ; > \stopMPpositiongraphic > > cxy is the center of the box. See the defn of initialize_box in mp-core.mp > for other values. I wish these were better documented. > > 2. Then define a position overlay that specifies the relation between the > anchors. > > \startpositionoverlay{arrow} > \setMPpositiongraphic{X-1}{mypos:arrow}{to=X-2} > \setMPpositiongraphic{X-2}{mypos:arrow}{to=X-3} > \stoppositionoverlay > > > 3. Define an overlay that is mapped to MP position overlay. > > \defineoverlay[arrow][\positionoverlay{arrow}] > > 4. Hook the overlay as a page background > > \setupbackgrounds[page][background=arrow] > > 5. Then everything will work. > > \starttext > > \section {Anchors and layers} > > In a previous section we saw that some \hpos{X-1} {words} were > \hpos{X-2}{circled} and connected by an \hpos{X-3} {arrow}. > As with most things in \CONTEXT, marking these words is separated > from declaring what to do with those words. This paragraph is keyed > in as: > > \stoptext > > Aditya > ___________________________________________________________________________________ > If your question is of interest to others as well, please add an entry to > the Wiki! > > maillist : ntg-context@ntg.nl / > http://www.ntg.nl/mailman/listinfo/ntg-context > webpage : http://www.pragma-ade.nl / http://tex.aanhet.net > archive : http://foundry.supelec.fr/projects/contextrev/ > wiki : http://contextgarden.net > ___________________________________________________________________________________ -- http://okle.pl ___________________________________________________________________________________ If your question is of interest to others as well, please add an entry to the Wiki! maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context webpage : http://www.pragma-ade.nl / http://tex.aanhet.net archive : http://foundry.supelec.fr/projects/contextrev/ wiki : http://contextgarden.net ___________________________________________________________________________________