;3D Utility                                                       EB
;Convert 3d polyline to 2d polyline
;..............................................................................
(defun c:p3p2 (/ eg cl en e nc fp pt)
 (princ "\n[Change 3D Polyline to 2D Polyline.]")
 (setq e  (entsel "  Select a 3DPoly: ")          ; get the header data
       en (car e)
       cl (if(=(cdr(assoc 70(entget en)))1)1)             ; closed flag 1=yes
       p1 (cdr(assoc 10(entget(entnext en))))
       p2 (cdr(assoc 10(entget(entnext(entnext en)))))
 )
 (command "ucs" "3" p1 p2 "")
 (setq fp (trans p1 0 1))                                  ; save first point
;       en (entnext en))                                   ; leave header
 (setvar "blipmode" 0)
 (command "pline")
 (command fp)                                             ; id first vertex
 (while (/=(cdr(assoc 0(setq eg(entget(setq en(entnext en))))))"SEQEND")
  (setq pt (trans(cdr(assoc 10 eg))0 1))
  (if pt (command pt))
  (if (and (not pt) cl)(command fp))
 );endwhile
 (command "")
 (command "ucs" "w")
 (setvar "blipmode" 1)
 (princ)
);end C:P3P2