\starttext

\startMPpage[offset=1mm]

        drawarrow (1cm,0cm) -- (0cm,0cm) withcolor red withtransparency(1,.5)  ;

    draw image (
        drawarrow (1cm,0cm) -- (0cm,0cm) withcolor red withtransparency(1,.5)  ;
    ) shifted (0,2mm) asgroup "" ;

    draw image (
        drawarrow (1cm,0cm) -- (0cm,0cm) withcolor red withtransparency(1,.5)  ;
    ) shifted (0,4mm) asgroup "isolated" ;

    draw image (
        drawarrow (1cm,0cm) -- (0cm,0cm) withcolor red withtransparency(1,.5)  ;
    ) shifted (0,6mm) asgroup "knockout" ;

    draw image (
        drawarrow (1cm,0cm) -- (0cm,0cm) withcolor red withtransparency(1,.5)  ;
    ) shifted (0,8mm) asgroup "isolated,knockout" ;

    addbackground withcolor green ;

\stopMPpage

\stoptext
