(DA)绘制有角度的直线

(defun C:DA(/ dis ent obj oldang pt0 ptn)
    (initget "E e")
    (setq oldang nil pt0 (getpoint "\n指定第一个点[拾取上一段(E)]:"))
    (while pt0
        (if (= (type pt0) 'str)
            (if (setq ent (entsel))
                (setq oldang (vla-get-Angle (setq obj (vlax-ename->vla-object (car ent)))) pt0 (vlax-safearray->list (vlax-variant-value (vla-get-EndPoint obj))))
                (setq pt0 nil)
            )
            (progn
                (setq ptn (getpoint pt0 "\n指定下一点:"))
                (if ptn
                    (progn
                        (if oldang
                            (progn
                                (cond
                                    ((< 0 (angle pt0 ptn))
                                        (setq
                                            oldang (+ oldang (- pi (angle pt0 ptn)) )
                                            dis (distance pt0 ptn)
                                        )
                                    )
                                    ((< (angle pt0 ptn) 0)
                                        (setq oldang (+ oldang (angle pt0 ptn)) dis (distance pt0 ptn))
                                    )
                                    ((= (angle pt0 ptn) 0)
                                        (setq oldang oldang dis (distance pt0 ptn))
                                    )
                                )
                            )
                            (setq oldang (angle pt0 ptn) dis (distance pt0 ptn))
                        )    
                        (entmake (list '(0 . "LINE") (cons 10 pt0) (cons 11 (polar pt0 oldang dis))))
                    )
                    (setq pt0 ptn)
                )
                ;;(setq pt0 (polar pt0 oldang dis))
            )
        )
    )
    (prin1)
)