IF polyLength THEN
        Wr.PutText(stderr,"recomputing sampling times...\n");
        (* Initial times are lengths along the polygonal: *)
        L := PZLR3Chain.LinearLengths(p, s);
        IF verbose THEN
          Wr.PutText(stderr, "polygonal length = " & FLR(L,8,5) & "\n");
        END;
        c.setTimes(s, L);
        (* Recompute lengths along interpolated curve: *)
        c.uniformize();
      END;