Does anyone know?

Using the latest LMTX, i try to clip some portion of an external  pdf
page, then resize that portion on top a new page.
i use the \clip command.

\starttext
\scale[width=100mm, hwight=100mm]{\clip[width=150mm, height=120mm,
hoffset=30mm, voffset=40mm]{\externalfigure[drawing.pdf]}} % incorrect

\scale[width=100mm, hwight=100mm]{\clip[width=150mm, height=120mm,
hoffset=30mm, voffset=136mm]{\externalfigure[drawing.pdf]}} % correct
\stoptext

I noticed that the voffset parameter *always* counts from the top/left
of the external source. Also if the source has its origin defined at the
lower/left corner.
Is that intentional?

It is confusing as when i place a rectangle on top of the clip i want to
extract from the source pdf, the x,w,w,h of that rectangle will not
match the parameter needed for the \clip command.

Or does there happen to be some snazzy tool out there to get the
coordinates of embedden images within a pdf?

.Floris