Flatten

[CADTutor]

Flatten

This routine will flatten a 3D drawing so that all Z values are set to zero. Although LDT has a specific function for this purpose, if you're using plain AutoCAD, this neat routine could save hours.

;   Flatten a 3D drawing 
;   Written by Eduard 
;   This command will set all elevations and points to zero, efectively flattening any 3D drawing. 
; 
(defun c:flat (/ total-nabor) 
  (vl-load-com) 
  (if 
    (setq total-nabor (ssget "x" '((410 . "model")))) 
     (progn 
       (setq total-nabor 
        (mapcar 'vlax-ename->vla-object 
          (mapcar 'cadr 
            (ssnamex total-nabor) 
 
          ) ;_ end of mapcar 
        ) ;_ end of mapcar 
       ) ;_ end of setq 
       (foreach  i '(1e99 -1e99) 
   (mapcar (function (lambda (x) 
           (vla-move x 
               (vlax-3d-point (list 0 0 0)) 
               (vlax-3d-point (list 0 0 i)) 
           ) ;_ end of vla-move 
         ) ;_ end of lambda 
     ) ;_ end of function 
     total-nabor 
   ) ;_ end of mapcar 
       ) ;_ end of foreach 
     ) ;_ end of progn 
  ) ;_ end of if 
  (princ) 
) ;_ end of defun

Download flat.lsp 0.93 KB

See the original topic for more details.

[Lee Mac]

A faster variation on the above:

(defun c:flat ( / acsel elv ) (vl-load-com)
  (if (ssget "_X" (list (cons 410 (getvar 'CTAB))))
    (progn
      (vlax-for obj
        (setq acsel
          (vla-get-ActiveSelectionSet
            (vla-get-ActiveDocument (vlax-get-acad-object))
          )
        )
        (foreach elv '(1e99 -1e99)
          (vl-catch-all-apply 'vla-move
            (list obj (vlax-3D-point '(0. 0. 0.)) (vlax-3D-point (list 0. 0. elv)))
          )
        )
      )
      (vla-delete acsel)
    )
  )
  (princ)
)

The above routine will not flatten 3D blocks - if you require these to be flattened also, they will need to be exploded before running the routine.