+ return AISObjectPtr();
+
+ if (!myScreenPlane) {
+ // initialize a default plane for dimension
+ GeomPointPtr anOrigin(new GeomAPI_Pnt(0., 0., 0.));
+ GeomDirPtr aNormal(new GeomAPI_Dir(0., 0., 1.));
+ myScreenPlane = GeomPlanePtr(new GeomAPI_Pln(anOrigin, aNormal));
+ }