\startuseMPgraphic{dummy}
pickup pencircle xscaled 5 rotated 30;
draw unitsquare scaled 20 withcmykcolor (0.3,0.4,0.6,0);
\stopuseMPgraphic

\starttext
\textdir TRT
This is text \useMPgraphic{dummy} and this is too
\stoptext
