TopoDS_Face aFace;
if( !aZoneShape.IsNull() )
aFace = TopoDS::Face( aZoneShape );
myPreviewPrs->setFace( aFace, true, true, "" );
TopoDS_Face aFace;
if( !aZoneShape.IsNull() )
aFace = TopoDS::Face( aZoneShape );
myPreviewPrs->setFace( aFace, true, true, "" );