# 'Nother little routine

• posted
All of my routines are geometrical in nature and are basically regular ACAD
commands with a purpose. Here's a cone-developing thing that was done last
week. Don't know why I never did this before.
A little info: the routine lets you pick 2 lines which would be the
generators of a cone. Please make sure that both lines are the same length
or you may get funky results. Oh yeah, it's in french, too.
Copy and share.
Dr Fléau
(defun c:conedevelop
(/ tmp lin1 lin2 p1 p2 p3 p4 p5 ray ang center oldvar)
(setq lin1 (entsel "Première ligne : ")
lin2 (entsel "Deuxième ligne :")
)
(setq oldvar (getvar "OSMODE"))
(setvar "OSMODE" 0)
;;; Extirpe les 4 points des extrémités
(setq p1 (cdr (assoc 10 (cdr (entget (car lin1)))))
p2 (cdr (assoc 11 (cdr (entget (car lin1)))))
p3 (cdr (assoc 10 (cdr (entget (car lin2)))))
p4 (cdr (assoc 11 (cdr (entget (car lin2)))))
)
;;; Trouve l'intersection
(setq p5 (inters p1 p2 p3 p4 nil))
(if (< (distance p5 p1) (distance p5 p2))
(setq tmp p1
p1 p2
p2 tmp
)
)
(if (< (distance p5 p3) (distance p5 p4))
(setq tmp p3
p3 p4
p4 tmp
)
)
;;; Calcule la longueur du cone complet
(setq dis (distance p1 p5))
;;; Trouve le rayon de la base du cone
(setq ray (/ (distance p1 p3) 2.0))
;;; Trouve l'angle de la développante
(setq ang (/ (* 360.0 ray) dis))
;;; Donne le point d'insertion
(setq center (getpoint "Donne le point d'insertion :"))
(setq temp (polar center (/ pi 2) (- dis (distance p1 p2))))
;;; Trace la ligne de départ du développement
(command "_.line" temp (polar temp (/ pi 2) (distance p1 p2)) "")
(command "_-array" (entlast) "" "P" center 2 ang "Y")
(command "_arc" "ce" center (polar temp (/ pi 2) (distance p1 p2)) "A"
ang)
(command "_arc" "ce" center (polar center (/ pi 2) (- dis (distance p1
p2))) "A" ang)
(setvar "OSMODE" oldvar)
)