How to calculate the area of 2D shapes in AutoCAD:

Thank you to the original poster; after drawing the shape in 1:1 scale, you can use the query command

To calculate the area, the shape must be closed and constitute a properly defined domain.

First, the surface to be queried must be a closed shape formed by lines; then this closed shape is converted into Pline lines, after which the perimeter can be calculated. It is then converted into a surface area, and the area can be determined (provided that the query command is first activated)

First create a region, then select the shape you want to query; right-click and choose Properties from the menu to find its area

Haha, I learned it; I’ve never used this before

You can just use the tool to query it directly.

Load the following lsp program, or add it to the menu:
(defun AreaSum (/ boundary+_lst boundary- boundary+ elast enext OS_hold msg olderr no insPt area pt doc mspace bdy-_ss idx )
(vl-load-com)
(setq doc (vla-get-activedocument (vlax-get-acad-object)))
(setq mspace (vla-get-modelspace doc))
(IF (< (ATOI (SUBSTR (GETVAR “ACADVER”) 1 2)) 16)
(PROGN
(PRINC “\nThis program can only run in AutoCAD 2004 or later versions.”)
(e*t)
)
)
(if (> (setq no (ent-number)) 1000)
(if (= (dos_msgbox (strcat “There are” (itoa no) “entities on the screen. Are you sure you want to continue?”) “Alert” 4 3) 3)
(e*t)
)
)
(setq olderr *error* msg „“ *error* AreaSum-error)
(setq boundary+_lst ‘())
(setq OS_hold (getvar “OSMODE”) echo_hold (getvar “CMDECHO”))
(setvar “OSMODE” 0)
(setvar “CMDECHO” 0)
_while (setq pt (getpoint “\nSelect an interior point (try to choose one close to the boundary): ”))
(setq elast (entlast) boundary+ nil boundary- nil)
(command “modemacro” “Generating boundaries, please wait…”))
(if (vl-catch-all-apply ‘bpoly (list pt))
(PROGN
(entdel (entlast))
(command “_.BPoly” “a” “o” “r” „“ pt„”)
(setq enext (entnext elast) bdy-_ss (ssadd))
_while enext
(if (eq enext (entnext elast))
(setq boundary+ enext)
(setq bdy-_ss (ssadd enext bdy-_ss))
)
; if (setq enext (entnext enext))
; while
(cond
((= (sslength bdy-_ss) 1)
(setq boundary- (ssname bdy-_ss 0))
)
((> (sslength bdy-_ss) 1)
(command “union” bdy-_ss „“)
(setq idx 0)
(repeat (sslength bdy-_ss)
(if (not (vlax-erased-p (ssname bdy-_ss idx)))
(setq boundary- (ssname bdy-_ss idx))
)
(setq idx (1+ idx))
)
); repeat
)
; cond
(if boundary-
(command “subtract” boundary+ „“ boundary- „“)
)
(if boundary+
(setq boundary+_lst (cons boundary+ boundary+_lst))
)
); progn
)
; IF (if boundary+_lst (highlight boundary+_lst 3) )
(command “modemacro” “”)
)
; while (setq area 0)
(if boundary+_lst
(PROGN
(foreach bdy boundary+_lst
(setq area (+ area (vla-get-area (vlax-ename->vla-object bdy))))
(entdel bdy)
)
; foreach
(if (setq insPt (getpoint “\nText insertion point: ”))
(vla-addText mspace (rtos area 2 2) (vlax-3d-point insPt) 3)
(PRINC (strcat “Total area: “ (rtos area 2 2)))
)
)
; PROGN
)
;if (setvar “OSMODE” OS_hold)
(setvar “CMDECHO” echo_hold)
(vlax-release-object doc)
(vlax-release-object mspace)
(PRINC)
)
;;
;;
;;
(defun highlight (entlst mode / en)
(foreach en entlst (redraw en mode))
)
;;
(defun ent-number (/ scrsize height width center llpt urpt enum ss)
(setq scrsize (getvar “SCREENSIZE”))
(setq height (getvar “VIEWSIZE”) width (* height (/ (car scrsize) (cadr scrsize))) )
(setq center (getvar “VIEWCTR”))
(setq llpt (polar (polar center pi (/ width 2.0)) (* pi 1.5) (/ height 2.0)) urpt (polar (polar center 0 (/ width 2.0)) (* pi 0.5) (/ height 2.0)) ))
(setq ss (ssget “w” llpt urpt))
(if ss
(setq enum (sslength ss))
(setq enum 0)
)
)
;;
(defun AreaSum-error (msg)
(if OS_hold
(setvar “OSMODE” OS_hold)
)
(if echo_hold
(setvar “CMDECHO” echo_hold)
)
(if (> (length boundary+_lst) 0)
(mapcar ‘entdel boundary+_lst )
)
(if olderr
(setq *error* olderr)
)
After loading, enter (AreaSum) in the command line to get the area of the enclosed region! ~~

Tool – Query; it’s very convenient to obtain.

After generating the polygonal area from the graphic, you can use a query tool to find the area