C++中的点云库：没有匹配函数来调用到

Question

，所以我有这样的代码中，我试图用点云库匹配一些描述我以前用其他的计算：

pcl::KdTreeFLANN<pcl::Narf36> matching = new pcl::KdTreeFLANN<pcl::Narf36>(false); 
pcl::KdTree<pcl::Narf36>::PointCloudConstPtr ptr_narf_descriptors(&narf_descriptors); 
matching.setInputCloud(ptr_narf_descriptors,NULL); 

std::vector<int> correspondence; 

// Check every descriptor computed for the scene. 
for (size_t i = 0; i < narf_descriptors2.size(); ++i) 
{ 
    std::vector<int> neighbors(1); 
    std::vector<float> squaredDistances(1); 
    // Ignore NaNs. 
    if (pcl_isfinite(narf_descriptors2.at(i).descriptor[0])) 
    { 
     // Find the nearest neighbor (in descriptor space)... 
     int neighborCount = matching.nearestKSearch(narf_descriptors2.at(i), 1, neighbors, squaredDistances); 
     // ...and add a new correspondence if the distance is less than a threshold 
     // (SHOT distances are between 0 and 1, other descriptors use different metrics). 
     if (neighborCount == 1 && squaredDistances[0] < 0.25f) 
     { 
      //correspondence.push_back(neighbors[0], static_cast<int>(i), squaredDistances[0]); 
      correspondence.push_back(neighbors[0]); 
     } 
    } 
} 

但compilator（令）说：

/home/adrian/PointCloudComparator/src/comparator.cpp: In function ‘void processNARF(std::string, std::string)’: 
/home/adrian/PointCloudComparator/src/comparator.cpp:270:50: error: no 
matching function for call to ‘pcl::KdTreeFLANN<pcl::Narf36>::setInputCloud(pcl::KdTree<pcl::Narf36>::PointCloudConstPtr&, NULL)’ 
matching.setInputCloud(ptr_narf_descriptors,NULL); 
              ^
/home/adrian/PointCloudComparator/src/comparator.cpp:270:50: note: candidate is: 
In file included from /usr/include/pcl-1.7/pcl/search/kdtree.h:44:0, 
      from /usr/include/pcl-1.7/pcl/search/pcl_search.h:44, 
      from /usr/include/pcl-1.7/pcl/features/impl/feature.hpp:44, 
      from /usr/include/pcl-1.7/pcl/features/feature.h:498, 
      from /usr/include/pcl-1.7/pcl/features/range_image_border_extractor.h:42, 
      from /home/adrian/PointCloudComparator/src/comparator.cpp:9: 
/usr/include/pcl-1.7/pcl/kdtree/kdtree_flann.h:146:7: note: 
void pcl::KdTreeFLANN<PointT, Dist>::setInputCloud(const PointCloudConstPtr&, const IndicesConstPtr&) [with PointT = pcl::Narf36; Dist = flann::L2_Simple<float>; pcl::KdTreeFLANN<PointT, 
Dist>::PointCloudConstPtr = boost::shared_ptr<const 
pcl::PointCloud<pcl::Narf36> >; pcl::KdTreeFLANN<PointT, 
Dist>::IndicesConstPtr = boost::shared_ptr<const std::vector<int> >] 
    setInputCloud (const PointCloudConstPtr &cloud, const 
IndicesConstPtr &indices = IndicesConstPtr()); 
^
            ^
make[2]: *** [CMakeFiles/comparator.dir/src/comparator.cpp.o] Error 1 
make[1]: *** [CMakeFiles/comparator.dir/all] Error 2 
make: *** [all] Error 2 

这是一个有点怪异，因为在类kdtree_Flann函数的定义是：

/** \brief Provide a pointer to the input dataset. 
    * \param[in] cloud the const boost shared pointer to a PointCloud message 
    * \param[in] indices the point indices subset that is to be used from \a cloud - if NULL the whole cloud is used 
    */ 
    void 
    setInputCloud (const PointCloudConstPtr &cloud, const IndicesConstPtr &indices = IndicesConstPtr()); 

是我写代码错了吗？ 或者它是不知道实际函数定义应来自哪里的编译器？

感谢和问候！

---

工作代码 - PCL库的1.7版本：

pcl::KdTreeFLANN<pcl::Narf36> matching = new pcl::KdTreeFLANN<pcl::Narf36>(false); 
pcl::KdTree<pcl::Narf36>::PointCloudConstPtr ptr_narf_descriptors(&narf_descriptors); 
matching.setInputCloud(ptr_narf_descriptors); 

std::vector<int> correspondence; 

Answer 1

你宣布std::vector<int> correspondence(); - 编译器会将其作为功能向前声明。

如果要定义变量 - 定义它不到底()：

std::vector<int> correspondence; 

第二个问题是，你通过NULL作为似乎是boost::shared_ptr类型的参数。 NULL是C风格的宏（请参阅http://www.cplusplus.com/reference/cstddef/NULL/?kw=NULL），并且不可能从它构造boost::shared_ptr（和std::智能指针）。

将NULL替换为nullptr（或boost::shared_ptr<const std::vector<int> >()），编译器将能够从该值构造boost::shared_ptr。