Now onto step two: how can I typeset each glyph in the formula individually such that it appears precisely in the right location?
I must be misreading something here, but I cannot figure out what 'the right location' means.
Since textext() always returns a single picture that can't be decomposed into smaller building blocks Hans suggested to textext() each desired snippet individually. So I tried --- \setupbodyfont[10pt] \starttext \startMPinclusions pickup pencircle scaled 0.05pt; defaultpen := savepen; picture crosshair; crosshair := image(draw fullcircle scaled 2pt; draw (0,-2pt)--(0,2pt); draw (-2pt,0)--(2pt,0); ); bboxmargin := 0; \stopMPinclusions \startMPpage for item within rawtextext("$(h,g)$"): draw bbox item withcolor 0.8white; draw item; endfor; draw crosshair; \stopMPpage \startMPpage draw bbox rawtextext("$($") withcolor 0.8white; draw rawtextext("$($"); draw bbox rawtextext("$h$") withcolor 0.8white; draw rawtextext("$h$"); draw bbox rawtextext("$,$") withcolor 0.8white; draw rawtextext("$,$"); draw bbox rawtextext("$g$") withcolor 0.8white; draw rawtextext("$g$"); draw bbox rawtextext("$)$") withcolor 0.8white; draw rawtextext("$)$"); draw crosshair; \stopMPpage \stoptext --- Clearly, this gives me each glyph individually but stacked on top of each other. What I need though is that the second figure looks exactly like the first one (with all glyphs in the right location) except that the grey bounding boxes appear per glyph. Thanks for your help, Oliver