ARX射线法判断点是否在多边形内

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1. //*************************************************************
   
2. //利用射线法判断一点是否在窗口内，如果在内部返回1，否则返回0
   
3. //其中输入参数pt是被判断点，boundarypt是辅助边界点，用于作射线用
   
4. //*********************1-14-2001 by Meishuli
   
5. 
   
6. int inwindow(ads_point pt,ads_point boundarypt,ads_name windowent)
   
7. {
   
8.   ads_name ent0;
   
9.   int rt;
   
10. 
    
11.   AcDbEntity *pent,*pwindowent;
    
12.     AcDbObjectId pentId,pwindowentId;
    
13.   AcGePoint3dArray points;
    
14.   int CrossPtsNum;
    
15.   AcGePoint3d Pts,BoundaryPts;
    
16.   AcDbObjectId auxlineId;
    
17.     Acad::ErrorStatus es;
    
18. 
    
19.   Pts.set(pt[X],pt[Y],0);
    
20.   BoundaryPts.set(boundarypt[X],boundarypt[Y],0);
    
21. 
    
22.   auxlineId=createLine(Pts,BoundaryPts);
    
23.   acdbEntLast(ent0);
    
24. 
    
25.   pwindowent=selectEntity(pwindowentId,windowent,AcDb::kForRead);
    
26.   pent=selectEntity(pentId,ent0,AcDb::kForRead);
    
27. 
    
28.   es=pwindowent->intersectWith(pent,AcDb::kOnBothOperands,points,0,0);
    
29.     if (es == Acad::eOk) {
    
30.       CrossPtsNum=points.length(); //计算交点的数量CrossPtsNum
    
31.         points.setLogicalLength(0);
    
32.   }
    
33.   else {
    
34.         acutPrintf("\nerror!--inwindow()\n");
    
35. 
    
36.       pent->close();
    
37.     acdbEntDel(ent0);
    
38.       pwindowent->close();
    
39.     return -1;
    
40.   }
    
41.   pent->close();
    
42.   acdbEntDel(ent0);
    
43. 
    
44.   pwindowent->close();
    
45.   if(CrossPtsNum % 2 == 0)
    
46.      rt = 0;
    
47.   else rt = 1;
    
48.   return rt;
    
49. }

//*************************************************************<br /> //利用射线法判断一点是否在窗口内，如果在内部返回1，否则返回0<br /> //其中输入参数pt是被判断点，boundarypt是辅助边界点，用于作射线用<br /> //*********************1-14-2001 by Meishuli<br /> <br /> int inwindow(ads_point pt,ads_point boundarypt,ads_name windowent)<br /> {<br />   ads_name ent0;<br />   int rt;<br /> <br />   AcDbEntity *pent,*pwindowent;<br />     AcDbObjectId pentId,pwindowentId;<br />   AcGePoint3dArray points;<br />   int CrossPtsNum;<br />   AcGePoint3d Pts,BoundaryPts;<br />   AcDbObjectId auxlineId;<br />     Acad::ErrorStatus es;<br /> <br />   Pts.set(pt[X],pt[Y],0);<br />   BoundaryPts.set(boundarypt[X],boundarypt[Y],0);<br /> <br />   auxlineId=createLine(Pts,BoundaryPts); <br />   acdbEntLast(ent0);<br /> <br />   pwindowent=selectEntity(pwindowentId,windowent,AcDb::kForRead);<br />   pent=selectEntity(pentId,ent0,AcDb::kForRead);<br /> <br />   es=pwindowent->intersectWith(pent,AcDb::kOnBothOperands,points,0,0);<br />     if (es == Acad::eOk) {<br />       CrossPtsNum=points.length(); //计算交点的数量CrossPtsNum<br />         points.setLogicalLength(0);<br />   }<br />   else {<br />         acutPrintf("\nerror!--inwindow()\n");<br /> <br />       pent->close();<br />     acdbEntDel(ent0);<br />       pwindowent->close();<br />     return -1;<br />   }<br />   pent->close();<br />   acdbEntDel(ent0);<br /> <br />   pwindowent->close();<br />   if(CrossPtsNum % 2 == 0)<br />      rt = 0;<br />   else rt = 1;<br />   return rt;<br /> }

1121443108qaz

https://blog.csdn.net/keng_s/article/details/52231046你这个好像不是很完善，根据它这篇博客所说，还要考虑如果得到的交点是多边形的端点的情况