Line Intersection

Hi



I 'am looking for a lisp routine which can indicate the intersection of a
line and arc.


( simular of AutoCAD command: inders. )



Tanks in Advance

Arnold

 

Something like this?

(defun intersection (ent1 ent2 / start leglen)
(and
ent1
ent2
(or (= (type ent1) 'ENAME)
(= (type ent1) 'VLA-OBJECT)
)
(or (= (type ent2) 'ENAME)
(= (type ent2) 'VLA-OBJECT)
)

)
(if (= (type ent1) 'ENAME)
(setq ent1 (vlax-ename->vla-object ent1))
)
(if (= (type ent2) 'ENAME)
(setq ent2 (vlax-ename->vla-object ent2))
)
(setq start (vlax-invoke ent1 "intersectwith" ent2 acextendnone)
leglen (* 0.03 (getvar "viewsize"))
)
(grdraw (polar start (angtof "135" 1) leglen)
(polar start (angtof "315" 1) leglen)
7)
(grdraw (polar start (angtof "45" 1) leglen)
(polar start (angtof "225" 1) leglen)
7)
start
)

Use like this:
(setq test (intersection (car (entsel)) (car (entsel))))

Jeff