\environment back-0

\startuseMPgraphic{mpos:par:color}
  for i=1 upto nofmultipars :
    fill multipars[i] withcolor
      if     multikind[i]="single" : "darkgray" ;
      elseif multikind[i]="first"  : "red" ;
      elseif multikind[i]="middle" : "green" ;
      elseif multikind[i]="last"   : "blue" ;
      else                         : "black" ;
      fi ;
  endfor ;
\stopuseMPgraphic

\setupindenting
  [medium,first]

\definecolumnset
  [four]
  [n=4,
   distance=7.5mm]

\definetextbackground
  [test]
  [location=text,
   mp=mpos:par:color,
   before=\blank,
   after=\blank]

\starttext

\starttexdefinition test #1#2#3
  \blank
  \bgroup
    \dontcomplain
    \hangindent#1\relax
    \hangafter #2\relax
    \parindent #3\relax
    \starttextbackground[test]%
      \simulatewords[n=200,m=500,min=1,max=5,color=gray]%
    \stoptextbackground
    \par
  \egroup
  \blank
\stoptexdefinition

\startcolumnset[four]

\startbuffer[a]
\test  {2cm} { -2} { 5mm}
\test  {2cm} { -2} { 0cm}
\test  {2cm} { -2} {-5mm}

\test  {2cm} { -5} { 5mm}
\test  {2cm} { -5} { 0cm}
\test  {2cm} { -5} {-5mm}

\stopbuffer

\startbuffer[b]
\test {-1cm} { -2} { 5mm}
\test {-1cm} { -2} { 0cm}
\test {-1cm} { -2} {-5mm}

\test {-1cm} { -5} { 5mm}
\test {-1cm} { -5} { 0cm}
\test {-1cm} { -5} {-5mm}
\stopbuffer

\startbuffer[c]
\test { 1cm} {  2} { 5mm}
\test { 1cm} {  2} { 0cm}
\test { 1cm} {  2} {-5mm}

\test { 1cm} {  5} { 5mm}
\test { 1cm} {  5} { 0cm}
\test { 1cm} {  5} {-5mm}
\stopbuffer

\startbuffer[d]
\test {-1cm} {  2} { 5mm}
\test {-1cm} {  2} { 0cm}
\test {-1cm} {  2} {-5mm}

\test {-1cm} {  5} { 5mm}
\test {-1cm} {  5} { 0cm}
\test {-1cm} {  5} {-5mm}
\stopbuffer

\dorecurse{2}{
    \dorecurse{1}{\getbuffer[a]}
    \dorecurse{1}{\getbuffer[b]}
    \dorecurse{1}{\getbuffer[c]}
    \dorecurse{1}{\getbuffer[d]}
}

\stopcolumnset

\stoptext
