title: How to import .ply files using PCL io::loadPLYFile?
body: <p>When importing a ply-file into my program I get an Error-message saying that something went wrong with the following message:</p>
  
  <pre><code>C:\Users\...\data\apple.ply:8: property 'list uint8 int32 vertex_indices' of element 'face' is not handled
  </code></pre>
  
  <p>I used a sample ply file from: <a href="https://people.sc.fsu.edu/~jburkardt/data/ply/apple.ply" rel="nofollow noreferrer">https://people.sc.fsu.edu/~jburkardt/data/ply/apple.ply</a></p>
  
  <p>I have already tried different ply files from different sources but none of them work. When debugging the program the io::loadPLYFile doesn't generate a valid pointcloud. Runtime Library for PCL and for my program are the same.</p>
  
  <pre><code>#include &lt;iostream&gt;
  #include &lt;pcl/io/pcd_io.h&gt;
  #include &lt;pcl/io/ply_io.h&gt;
  #include &lt;pcl/point_types.h&gt;
  #include &lt;pcl/search/kdtree.h&gt;
  #include &lt;pcl/features/normal_3d_omp.h&gt;
  #include &lt;pcl/surface/marching_cubes_rbf.h&gt;
  
  using namespace pcl;
  using namespace std;
  
  int
    main (int argc, char** argv)
   {
    PointCloud&lt;PointXYZ&gt;::Ptr cloud (new PointCloud&lt;PointXYZ&gt;);
    std::cout &lt;&lt; "Start Debug?" &lt;&lt; std::endl;
    std::cin.ignore();
  
    if(io::loadPLYFile&lt;PointXYZ&gt; (argv[1], *cloud) == -1){
      cout &lt;&lt; "ERROR: couldn't find file" &lt;&lt; endl;
      return (1);
    } else {
      cout &lt;&lt; "loaded" &lt;&lt; endl;
  
      NormalEstimationOMP&lt;PointXYZ, Normal&gt; ne;
      search::KdTree&lt;PointXYZ&gt;::Ptr tree1 (new search::KdTree&lt;PointXYZ&gt;);
      tree1-&gt;setInputCloud (cloud);
      ne.setInputCloud (cloud);
      ne.setSearchMethod (tree1);
      ne.setKSearch (20);
      PointCloud&lt;Normal&gt;::Ptr normals (new PointCloud&lt;Normal&gt;);
      ne.compute (*normals);
  </code></pre>
  
  <p>I would expect the PCL function io::loadPLYFile to load the files properly as described in the documentation <a href="http://docs.pointclouds.org/1.3.1/group__io.html" rel="nofollow noreferrer">http://docs.pointclouds.org/1.3.1/group__io.html</a></p>