[metapost] pdftex \pdflastxpos for metapost?

[Hartmut Henkel]

Hi,

i'm trying to produce a page-size overlay with mpost over a page made by
pdftex, where the \pdflastxpos and \pdflastypos coordinate pairs from
certain anchor points are written to some .pos file by pdftex and then
read in by mpost.

Problem is that \pdflastx/ypos are integers in sp units, too large for
mpost to handle. Now how to reduce these integers? Is it possible to do
this already on the pdftex side during/inside the \write{} by some
division macro? That would be nice. Or maybe by a slow scaling function
via scantokens on the mpost side? Currently the easiest seems to
preprocess the .pos file by awk, which is ugly due to the additional
step. It looks as if it would be easier if there were some
\pdflastxcoord and \pdflastycoord as dimen registers.

Any hints welcome.

Regards, Hartmut