minimum elevation of 3d face

Hello

what code can get minimum elevation of 3d faces

What do you mean with minimum elevation... 3DFace entity consist of 3 - 4 points that can be coplanar and also may not if there are 4... Do you want to get Z coordinate of point that is the lowest, or something else?

sorry for that

please find attached dwg

3dface.dwg

Pass a 3DFACE ename to this:

[b][color=BLACK]([/color][/b]defun minz [b][color=FUCHSIA]([/color][/b]e / ed mz[b][color=FUCHSIA])[/color][/b]
 [b][color=FUCHSIA]([/color][/b]and [b][color=NAVY]([/color][/b]setq ed [b][color=MAROON]([/color][/b]entget e[b][color=MAROON])[/color][/b][b][color=NAVY])[/color][/b]
      [b][color=NAVY]([/color][/b]setq mz [b][color=MAROON]([/color][/b]apply 'min [b][color=GREEN]([/color][/b]list [b][color=BLUE]([/color][/b]nth 3 [b][color=RED]([/color][/b]assoc 10 ed[b][color=RED])[/color][/b][b][color=BLUE])[/color][/b]
                                 [b][color=BLUE]([/color][/b]nth 3 [b][color=RED]([/color][/b]assoc 11 ed[b][color=RED])[/color][/b][b][color=BLUE])[/color][/b]
                                 [b][color=BLUE]([/color][/b]nth 3 [b][color=RED]([/color][/b]assoc 12 ed[b][color=RED])[/color][/b][b][color=BLUE])[/color][/b]
                                 [b][color=BLUE]([/color][/b]nth 3 [b][color=RED]([/color][/b]assoc 13 ed[b][color=RED])[/color][/b][b][color=BLUE])[/color][/b][b][color=GREEN])[/color][/b][b][color=MAROON])[/color][/b][b][color=NAVY])[/color][/b][b][color=FUCHSIA])[/color][/b]
mz[b][color=BLACK])[/color][/b]

-David

very thanks david

i have a selection set of 3d face

(setq 3df (ssget '((0 . "3DFACE"))))

how can i pass ename from 3df

Or condensing David's:

(defun minz ( e )
   (setq e (entget e))
   (apply 'min (mapcar '(lambda ( x ) (cadddr (assoc x e))) '(10 11 12 13)))
)

For selection set:

(defun minzss ( s / i m )
   (setq m 1e308)
   (repeat (setq i (sslength s))
       (setq m (min m (minz (ssname s (setq i (1- i))))))
   )
)

(minzss (ssget '((0 . "3DFACE"))))

(setq m 1e308)

........

........

It's cheating really; strictly I should write it:

(defun minzss ( s / i m )
   (setq i (1- (sslength s))
         m (minz (ssname s i))
   )
   (repeat i
       (setq m (min m (minz (ssname s (setq i (1- i))))))
   )
)

In case there is a face with vertex at minimum elevation 1.79e308

this is what i want to do

(defun minz (e / ed mz)
 (and (setq ed (entget e))
      (setq mz (apply 'min (list (nth 3 (assoc 10 ed))
                                 (nth 3 (assoc 11 ed))
                                (nth 3 (assoc 12 ed))
                                (nth 3 (assoc 13 ed))))))
mz)
(defun c:min(/)
(setq 3DF (ssget '((0 . "3DFACE"))))
(minz)
 (print (rtos minz 2 2))

)

so how can i pass e here or pass 3df from e or other

because i lost

As shown in my earlier post, you can pass the selection set to the posted 'minzss' function:

(defun minz ( e )
   (setq e (entget e))
   (apply 'min (mapcar '(lambda ( x ) (cadddr (assoc x e))) '(10 11 12 13)))
)

(defun minzss ( s / i m )
   (setq i (1- (sslength s))
         m (minz (ssname s i))
   )
   (repeat i
       (setq m (min m (minz (ssname s (setq i (1- i))))))
   )
)

(defun c:test ( / sel )
   (if (setq sel (ssget '((0 . "3DFACE"))))
       (minzss sel)
   )
)

thank you Lee Mac

for reply and to all posted here

Hello

what code can get minimum elevation of 3d faces

If you are using AutoCAD for Windows you can get the maximum and minimum extents (and hence the maximum and minimum elevations) using the vla-GetBoundingBox function. This works for any entity, not only 3DFaces.

I've put up a simple example that displays the Minimum and maximum elevations for the selected object:

(defun c:show-elev  (/ minpt maxpt)
 (vl-load-com)
 (vla-GetBoundingBox
   (vlax-ename->vla-object
     (car (entsel "\nSelect entity: ")))
   'minpt
   'maxpt)
 (alert
   (strcat "Minimum elevation:\t"
           (rtos (last (vlax-safearray->list minpt)) 2 4)
           "\nMaximum elevation:\t"
           (rtos (last (vlax-safearray->list maxpt)) 2 4))))

This other one displays the maximum and minimum boundingbox corner:

(defun c:show-extents  (/ minpt maxpt)
 (vl-load-com)
 (vla-GetBoundingBox
   (vlax-ename->vla-object
     (car (entsel "\nSelect entity: ")))
   'minpt
   'maxpt)
 (alert
   (strcat "Minimum boundingbox corner:\t"
           (vl-princ-to-string (vlax-safearray->list minpt))
           "\nMaximum boundingbox corner:\t"
           (vl-princ-to-string (vlax-safearray->list maxpt)))))

thank you Lee Mac

for reply and to all posted here

You're welcome