(vl-load-com)
(if vs:autor (vlr-remove vs:autor))
(setq vs:autor (VLR-SysVar-Reactor nil '((:vlr-sysvarchanged . sysvarchg))) )
(setq _vsautoinproc nil)
(defun _isortho (badval / )
 (and ; orto pohledy:
 (or (equal (car badval) 0.0 0.000001)(equal (cadr badval) 0.0 0.000001))
 (or (equal (car badval) 0.0 0.000001)(equal (caddr badval) 0.0 0.000001))
 (or (equal (cadr badval) 0.0 0.000001)(equal (caddr badval) 0.0 0.000001))
 )
)
;-----------
 (defun sysvarchg (r data / varname badval adoc VpEnt vport vsname)
 
  (if (not _vsautoinproc)(progn ; in proc?
 (setq _vsautoinproc T)
 (setq varname (car data))
 (setq badval (getvar varname))
(PRINC "\n")(princ varname)(princ "=")(princ badval)
 (if (= varname "VIEWDIR")(progn
;(PRINT "*SW*")
  (setq adoc (vla-get-activedocument (vlax-get-acad-object)))
;(if (> (atoi (substr (getvar "ACADVER") 1 2)) 16) ; JENOM!
  (if (= (getvar "TILEMODE") 1)
  (setq VpEnt (vlax-vla-object->ename (setq vport (vla-get-activeviewport adoc))))
  (setq VpEnt (vlax-vla-object->ename (setq vport (vla-get-activepviewport adoc))))
  )
  (setq vsname (cdr (assoc 2 (entget (cdr (assoc 348 (entget VpEnt)))))))
 
 ;(PRINT vsname)
  (if (< (getvar "CMDACTIVE") 2)(progn ; nop nebo bezny prikaz
  (if (and (_isortho badval)
     (/= vsname "Wireframe")
   )
   (vla-sendcommand adoc "_VSCURRENT _2d ") ; go ORTO
   ;(vla-put-VisualStyle vport 1)
  )
  (if (and (not (_isortho badval))
     ;(= vsname "Wireframe")
   )
   (vla-sendcommand adoc "_VSCURRENT _rea ") ; go REALISTIC
  )
  )) ; jde poslat sendocmmand
 )) ; jde o VIEWDIR
 (setq _vsautoinproc nil)
  ))
 )