I want to use the positionoverlay mechanism in several different figures (according to the metafun manual "Anchors and layers").
The problem is that the overlays show up in the last figure only, not in the first.
If I do not typeset the second overlayseries, the first does appear.
It looks like only the last overlayseries is kept.
Why is this and how to remedy this?


Like this with several names overlay names:
\def\startoverlaygraphics#1{%
\startpositionoverlay{#1}%
}
\def\stopoverlaygraphics#1{%
\stoppositionoverlay
\defineoverlay[#1][\positionoverlay{#1}]
\setupbackgrounds[page][background={foreground,#1}]
}
 Using it in:

\startoverlaygraphics{graphics-1}
\setMPpositiongraphic{A1}{syllabus:arrow}{to=B1}
etc.
\stopoverlaygraphics{graphics-1}

...\hpos{A1}{}...\hpos{B1}{}...

\startoverlaygraphics{graphics-2}
\setMPpositiongraphic{E1}{syllabus:arrow}{to=F1}
etc.
\stopoverlaygraphics{graphics-2}

...\hpos{E1}{}...\hpos{F1}{}...

Arrows drawn with:
\setupMPvariables[syllabus:arrow]%
[linestyle={dashed evenly},%
linesize=\tableframethickness,
coloring=FrameColor,%
axoff=0pt, ayoff=0pt, bxoff=0pt, byoff=0pt]
\startMPpositiongraphic{syllabus:arrow}{coloring}
pair a, b;
initialize_box(\MPpos{\MPvar{from}});
a := cxy;
initialize_box(\MPpos{\MPvar{to}});
b:= cxy;
pickup pencircle scaled \MPvar{linesize};
drawarrow (a + (\MPvar{axoff},\MPvar{ayoff})) --
(b + (\MPvar{bxoff},\MPvar{byoff}))
\MPvar{linestyle} withcolor \MPvar{coloring};
anchor_box(\MPanchor{\MPvar{from}});
\stopMPpositiongraphic
\endinput


Hans van der Meer