Hello MetaFun Math Lovers, I am using MetaFun to attach diagrams to formulas. Both the physics and the typesetting are going great! I attached a sample below, to give a taste of what I am trying to do. This page of actual calculations has examples of almost everything I need. It’s a lot, but it is all working. Right now the interface is terrible, but effective. Thanks to Hans and Mikael for many helpful hints! I am still using \hpos and \setMPpositiongraphic, because I haven't figured out how to pass information from \mathboxanchored and \connectboxanchors to my MetaPost code. Here is the code for the connectors: \startMPpositiongraphic{mypos:contract} path pa, pb, pab ; numeric na, nb ; string ta, tb, hand, product ; ta := mpvars("from") ; tb := mpvars("to") ; stemshiftfrom := (EmWidth/8)*mpvarn("startstem") ; stemshiftto := (EmWidth/8)*mpvarn("stopstem") ; hand := mpvars("hand") ; product := mpvars("product") ; delta := mpvard("distance") ; na := positionpage(ta) ; % page number of a nb := positionpage(tb) ; % page number of b pa := positionbox(ta) ; % box of a pb := positionbox(tb) ; % box of b if hand = "right" : z1 = 0.5[llcorner pa,lrcorner pa] shifted (stemshiftfrom, -ExHeight/4) ; z2 = 0.5[llcorner pb,lrcorner pb] shifted (stemshiftto, -ExHeight/4) ; y3 = min(y1,y2) - ExHeight/2 -delta; else : z1 = 0.5[ulcorner pa,urcorner pa] shifted (stemshiftfrom, ExHeight/4) ; z2 = 0.5[ulcorner pb,urcorner pb] shifted (stemshiftto, ExHeight/4) ; y3 = max(y1,y2) + ExHeight/2 +delta; fi ; if na = nb : % Check that positions are on the same page pickup pencircle scaled 0.6pt ; if product = "sym" : draw z1 -- (x1,y3+ExHeight/2) ; draw z2 -- (x2,y3+ExHeight/2) ; pickup pencircle scaled 1.2pt ; draw (x1-EmWidth/8,y3) -- (x2+EmWidth/8,y3) ; else : pab := z1 -- (x1,y3) -- (x2,y3) -- z2{down} ; draw pab ; fi ; positioninregion ; fi ; \stopMPpositiongraphic A connector command might look something like this: \setMPpositiongraphic{X-1}{mypos:contract}{to=X-2,product=sym,startstem=-2,stopstem=2,distance=0.5ex} All of the key=value pairs in the last argument of \setMPpositiongraphic pop right up in my MetaPost code with mpvar(“key”). I haven’t been able to follow this with \mathboxanchored and \connectboxanchors. My two questions are: 1) Can I use \setMPpositiongraphic with \mathboxanchored? That would allow me to go straight to my MetaPost code without the \connectboxanchors interface 2) Can I tell \connectboxanchors to use my MetaPost code and pass key=value pairs like I do with \setMPpositiongraphic? Thanks for any hints! Gavin