[求助]任意两条线的交点坐标

李龙山

任意两条线的交点坐标，包括PL线与PL线，pl线与LINE，PL线与圆弧，pl线与圆等等，包括它们之间的任意组合方式，得到交点坐标表。请大侠帮助。谢谢

半夜星星

任意空间的线如果Z坐标不一致的，还是求不到交点啊，好难啊

taoyi0727

谢谢8楼的代码  正用的上

hisum

我想要得到交点的Z坐标，如何实现？

你去看一看置顶帖，里面就有。

Andyhon

网内搜一下 vla-IntersectWith

李龙山

(defun m_IntersectWith(m_ent1 m_ent2 / m_obj1 m_obj2 m_objcopy1 m_objcopy2 m_jdtab m_jdtab1 i)
  ;;适用对象: Line、Polyline、LWPolyline、Circle、Arc、Ellipse、3dPolyline、Spline
  ;;支持求空间虚交点，但Z坐标始终为0.0，要求Z坐标，请用(vlax-curve-getClosestPointToProjection)函数
  (setq m_obj1 (vlax-ename->vla-object m_ent1))
  (setq m_obj2 (vlax-ename->vla-object m_ent2))
 
  (setq m_objcopy1 (vla-copy m_obj1));;复制第一条曲线实体
  (setq m_objcopy2 (vla-copy m_obj2));;复制第二条曲线实体
 
  (setq m_objcopy1 (m_ShadowToXY m_objcopy1));;得到投影实体
  (setq m_objcopy2 (m_ShadowToXY m_objcopy2));;得到投影实体

 
  (setq m_jdtab1 (vla-intersectwith m_objcopy1 m_objcopy2 acExtendnone));;得到交点集
 
  (if (> (vlax-safearray-get-u-bound (vlax-variant-value m_jdtab1) 1) 1);;判断有无交点
      (progn
(setq m_jdtab1 (vlax-safearray->list (vlax-variant-value m_jdtab1)));;safearray数组转换为list表
(setq i 0)
(repeat (/ (length m_jdtab1) 3)
   (setq m_jd (list (nth i m_jdtab1) (nth (+ 1 i) m_jdtab1) (nth (+ 2 i) m_jdtab1)));;取得一个交点
   (setq m_jdtab (cons m_jd m_jdtab));;构造交点表（(第一个交点) (第二个交点)。。。）
   (setq i (+ 3 i))
)
      )
      (princ"\n两曲线无交点!")
  )
 
  (vla-delete m_objcopy1);;删除复制的第一条曲线实体
  (vla-delete m_objcopy2);;删除复制的第二条曲线实体
 
  (setq m_jdtab m_jdtab);;返回交点表，无交点返回nil
)

(defun m_ShadowToXY(m_obj / m_objname m_pts m_pts1 i)
  ;;对曲线实体m_obj创建一个投影至xy平面的曲线实体，即对曲线实体上每个控制点的z坐标值置为0.0
  ;;输入曲线实体(vla对象)
  ;;返回投影实体(vla对象)
  (setq m_objname (vla-get-objectname m_obj));;取得实体的类型名称
  (m_princ "\nObjectName：" m_objname)
  (cond
    ((= "AcDbSpline" m_objname);;样条曲线(Spline)
     (setq i 0)
     (setq m_pts (vlax-variant-value (vla-get-fitpoints m_obj)));;取得样条曲线的拟合点
     (setq m_pts1 (vlax-variant-value (vla-get-controlpoints m_obj)));;取得样条曲线的控制点
     (repeat (vla-get-numberoffitpoints m_obj);;循环
       (vlax-safearray-put-element m_pts (+ i 2) 0.0);;改变每个拟合点的z值为0.0
       (setq i (+ i 3))
     )
     (vla-put-fitpoints m_obj m_pts);;更改曲线拟合点属性

     (setq i 0)
    
     (repeat (vla-get-numberofcontrolpoints m_obj);;循环
       (vlax-safearray-put-element m_pts1 (+ i 2) 0.0);;改变每个控制点的z值为0.0
       (setq i (+ i 3))
     )
     (vla-put-controlpoints m_obj m_pts1);;更改曲线控制点属性
    )
   
    ((= "AcDb3dPolyline" m_objname);;三维多段线(3dpolyline)
     (setq i 0)
     (setq m_pts (vlax-variant-value (vla-get-coordinates m_obj)));;取得3维多段线的控制点
     (repeat (/ (length (vlax-safearray->list m_pts)) 3)
       (vlax-safearray-put-element m_pts (+ i 2) 0.0)
       (setq i (+ i 3))
     )
     (vla-put-coordinates m_obj m_pts)
    )
   
    ((= "AcDbLine" m_objname);;直线(line)
     (setq i 0)
     (setq m_pts (vlax-variant-value (vla-get-startpoint m_obj)));;取得直线的起点座标
     (setq m_pts1 (vlax-variant-value (vla-get-endpoint m_obj)));;取得直线的端点座标
     (vlax-safearray-put-element m_pts 2 0.0);;改变起点座标z值为0.0
     (vlax-safearray-put-element m_pts1 2 0.0)
     (vla-put-startpoint m_obj m_pts)
     (vla-put-endpoint m_obj m_pts1)
    )

    ((or (= "AcDbCircle" m_objname);;园(circle)
  (= "AcDbArc" m_objname);;圆弧(arc)
  (= "AcDbEllipse" m_objname);;椭圆及椭圆弧(ellipse)
     )
     (setq m_pts (vlax-variant-value (vla-get-center m_obj)));;取得中心点座标
     (vlax-safearray-put-element m_pts 2 0.0);;改变中心点座标z值为0.0
     (vla-put-center m_obj m_pts)
    )
   
    ((or (= "AcDbPolyline" m_objname);;多段线(polyline、lwpolyline)
  (= "AcDb2dPolyline" m_objname);;拟合的2维多段线(polyline、lwpolyline)
     )
     (vla-put-elevation m_obj 0.0);;改变标高值为0.0
    )
  )
  (setq m_obj m_obj)
)

(defun C:test(/ m_ent1 m_ent2 m_jdtab)
 (vl-load-com)
 
 (setq m_ent1 (car (entsel "\n请选择第一条曲线: ")))
  (setq m_ent2 (car (entsel "\n请选择第二条曲线: ")))
  (setq ZL-GETINTERS ( m_ent1 m_ent2))
  (princ"\n交点表: ")(princ ZL-GETINTERS)
  (princ)
)

Andyhon大侠

帮我看看，测试后也不返回交点列表呀，也不知道哪里出错

李龙山

测试通过了。

(defun c:get_int0( / ent1 ent2 ps)
  (setq ent1 (car (entsel "选择第一实体:")))
  (setq ent2 (car (entsel "选择第二实体:")))
  (print)
  (setq ps (obj_int ent1 ent2))
)
;~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
;功能:返回两个对象的所有交点
;参数: ent1、ent2 均为ename对象
(defun obj_int (ent1 ent2 / ax_ent_1 ax_ent_2 intpoints points i)
   (setq ax_ent_1 (vlax-ename->vla-object ent1)
         ax_ent_2 (vlax-ename->vla-object ent2)
   )
   (setq intpoints (vla-intersectwith ax_ent_1 ax_ent_2 acextendnone))
   (setq intpoints (vlax-variant-value intpoints))
   (setq i 0)
   (if (> (vlax-safearray-get-u-bound intpoints 1) 0)
     (repeat (/ (+ 1
               (- (vlax-safearray-get-u-bound intpoints 1)
                  (vlax-safearray-get-l-bound intpoints 1)
               )
            )
            3
         )
       (setq points (append points (list (list
         (vlax-safearray-get-element intpoints i)
         (vlax-safearray-get-element intpoints (+ i 1))
         (vlax-safearray-get-element intpoints (+ i 2))
       )))
       )
       (setq i (+ 3 i))
     )
   )
   points
)

Andyhon

提供另一种调用做比较
http://www.menziengineering.ch/Downloads/Download.htm
VxGetInters - Returns all intersection points between two objects

李龙山

谢谢Andyhon

yoyoho

(defun m_IntersectWith (m_ent1 m_ent2 / m_obj1 m_obj2 m_objcopy1 m_objcopy2 m_jdtab m_jdtab1 i)
  ;;适用对像: Line、Polyline、LWPolyline、Circle、Arc、Ellipse、3dPolyline、Spline
  ;;支持求空间虚交点，但Z坐标始终为0.0，要求Z坐标，请用(vlax-curve-getClosestPointToProjection)函数
  (setq m_obj1 (vlax-ename->vla-object m_ent1))
  (setq m_obj2 (vlax-ename->vla-object m_ent2))

  (setq m_objcopy1 (vla-copy m_obj1));;复制第一条曲线实体
  (setq m_objcopy2 (vla-copy m_obj2));;复制第二条曲线实体

  (setq m_objcopy1 (m_ShadowToXY m_objcopy1));;得到投影实体
  (setq m_objcopy2 (m_ShadowToXY m_objcopy2));;得到投影实体

  (setq m_jdtab1 (vla-intersectwith m_objcopy1 m_objcopy2 acExtendnone));;得到交点集

  (if (> (vlax-safearray-get-u-bound (vlax-variant-value m_jdtab1) 1) 1);;判断有无交点
      (progn
(setq m_jdtab1 (vlax-safearray->list (vlax-variant-value m_jdtab1)));;safearray数组转换为list表
(setq i 0)
(repeat (/ (length m_jdtab1) 3)
   (setq m_jd (list (nth i m_jdtab1) (nth (+ 1 i) m_jdtab1) (nth (+ 2 i) m_jdtab1)));;取得一个交点
   (setq m_jdtab (cons m_jd m_jdtab));;构造交点表（(第一个交点) (第二个交点)。。。）
   (setq i (+ 3 i))
)
      )
      (princ"\n两曲线无交点!")
  )

  (vla-delete m_objcopy1);;删除复制的第一条曲线实体
  (vla-delete m_objcopy2);;删除复制的第二条曲线实体

  (setq m_jdtab m_jdtab);;返回交点表，无交点返回nil
)

(defun m_ShadowToXY(m_obj / m_objname m_pts m_pts1 i)
  ;;对曲线实体m_obj创建一个投影至xy平面的曲线实体，即对曲线实体上每个控制点的z坐标值置为0.0
  ;;输入曲线实体(vla对像)
  ;;返回投影实体(vla对像)
  (setq m_objname (vla-get-objectname m_obj));;取得实体的类型名称
;  (m_princ "\nObjectName：" m_objname)

  (cond
    ((= "AcDbSpline" m_objname);;样条曲线(Spline)
     (setq i 0)
     (setq m_pts (vlax-variant-value (vla-get-fitpoints m_obj)));;取得样条曲线的拟合点
     (setq m_pts1 (vlax-variant-value (vla-get-controlpoints m_obj)));;取得样条曲线的控制点
     (repeat (vla-get-numberoffitpoints m_obj);;循环
       (vlax-safearray-put-element m_pts (+ i 2) 0.0);;改变每个拟合点的z值为0.0
       (setq i (+ i 3))
     )
     (vla-put-fitpoints m_obj m_pts);;更改曲线拟合点属性

     (setq i 0)

     (repeat (vla-get-numberofcontrolpoints m_obj);;循环
       (vlax-safearray-put-element m_pts1 (+ i 2) 0.0);;改变每个控制点的z值为0.0
       (setq i (+ i 3))
     )
     (vla-put-controlpoints m_obj m_pts1);;更改曲线控制点属性
    )

    ((= "AcDb3dPolyline" m_objname);;三维多段线(3dpolyline)
     (setq i 0)
     (setq m_pts (vlax-variant-value (vla-get-coordinates m_obj)));;取得3维多段线的控制点
     (repeat (/ (length (vlax-safearray->list m_pts)) 3)
       (vlax-safearray-put-element m_pts (+ i 2) 0.0)
       (setq i (+ i 3))
     )
     (vla-put-coordinates m_obj m_pts)
    )

    ((= "AcDbLine" m_objname);;直线(line)
     (setq i 0)
     (setq m_pts (vlax-variant-value (vla-get-startpoint m_obj)));;取得直线的起点座标
     (setq m_pts1 (vlax-variant-value (vla-get-endpoint m_obj)));;取得直线的端点座标
     (vlax-safearray-put-element m_pts 2 0.0);;改变起点座标z值为0.0
     (vlax-safearray-put-element m_pts1 2 0.0)
     (vla-put-startpoint m_obj m_pts)
     (vla-put-endpoint m_obj m_pts1)
    )

    ((or (= "AcDbCircle" m_objname);;园(circle)
  (= "AcDbArc" m_objname);;圆弧(arc)
  (= "AcDbEllipse" m_objname);;椭圆及椭圆弧(ellipse)
     )
     (setq m_pts (vlax-variant-value (vla-get-center m_obj)));;取得中心点座标
     (vlax-safearray-put-element m_pts 2 0.0);;改变中心点座标z值为0.0
     (vla-put-center m_obj m_pts)
    )

    ((or (= "AcDbPolyline" m_objname);;多段线(polyline、lwpolyline)
  (= "AcDb2dPolyline" m_objname);;拟合的2维多段线(polyline、lwpolyline)
     )
     (vla-put-elevation m_obj 0.0);;改变标高值为0.0
    )
  )
  (setq m_obj m_obj)
)

(defun C:test (/ m_ent1 m_ent2 m_jdtab)
; (vl-load-com)

 (setq m_ent1 (car (entsel "\n请选择第一条曲线: ")))
  (setq m_ent2 (car (entsel "\n请选择第二条曲线: ")))
  (setq ZL-GETINTERS (m_IntersectWith m_ent1 m_ent2))
  (princ"\n交点表: ")(princ ZL-GETINTERS)
  (princ)
)

;Andyhon大侠

;帮我看看，测试后也不返回交点列表呀，也不知道哪里出错

;AUTOCAD 2008 測試O.K

Andyhon

向原创作者求助可能要快些有回应
若能附上您调试失败的文件(*.Dwg)更利于厘清症结所在

lzy9788

请问VLX怎么可以实现不相交的两实体延伸所得到的交点？

 

呵呵，搞定了