\pstGeonode[PosAngle={0,-45}](.5,1){O}(-1.5,-1.2){A}(.5,-.8){B}
\pstHomO[HomCoef=.62, PosAngle=-45]{O}{A,B}[C,D]
\psset{linecolor=green, nodesep=-1}
\pstLineAB{A}{O}\pstLineAB{B}{O}
\psset{linecolor=red, nodesep=-.5}
\pstLineAB{A}{B}\pstLineAB{C}{D}