test_octree.cpp

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#include <gtest/gtest.h>

#include <vector>

#include <stdio.h>

using namespace std;

#include <pcl/common/time.h>
#include <pcl/point_cloud.h>
#include <pcl/point_types.h>

using namespace pcl;

#include <pcl/octree/octree.h>
#include <pcl/octree/octree_impl.h>

using namespace octree;

TEST (PCL, Octree_Test)
{

  unsigned int i, j;
  int data[256];

  // create octree instance
  OctreeBase<int> octreeA;
  OctreeBase<int> octreeB;

  // set octree depth
  octreeA.setTreeDepth (8);
  octreeB.setTreeDepth (8);

  struct MyVoxel
  {
    unsigned int x;
    unsigned int y;
    unsigned int z;
  };
  MyVoxel voxels[256];

  srand (static_cast<unsigned int> (time (NULL)));

  // generate some voxel indices
  for (i = 0; i < 256; i++)
  {
    data[i] = i;

    voxels[i].x = i;
    voxels[i].y = 255 - i;
    voxels[i].z = i;

    // add data to leaf node voxel
    octreeA.addData (voxels[i].x, voxels[i].y, voxels[i].z, data[i]);
  }

  int LeafNode;
  for (i = 0; i < 128; i++)
  {
    // retrieve data from leaf node voxel
    octreeA.getData (voxels[i].x, voxels[i].y, voxels[i].z, LeafNode);
    // check if retrieved data is identical to data[]
    ASSERT_EQ(LeafNode, data[i]);
  }

  for (i = 128; i < 256; i++)
  {
    // check if leaf node exists in tree
    ASSERT_EQ( octreeA.existLeaf(voxels[i].x,voxels[i].y,voxels[i].z), true);

    // remove leaf node
    octreeA.removeLeaf (voxels[i].x, voxels[i].y, voxels[i].z);

    //  leaf node shouldn't exist in tree anymore
    ASSERT_EQ( octreeA.existLeaf(voxels[i].x,voxels[i].y,voxels[i].z), false);
  }

  // test serialization

  std::vector<char> treeBinaryA;
  std::vector<char> treeBinaryB;

  std::vector<int> leafVectorA;
  std::vector<int> leafVectorB;

  // serialize tree - generate binary octree description
  octreeA.serializeTree (treeBinaryA);

  // deserialize tree - rebuild octree based on binary octree description
  octreeB.deserializeTree (treeBinaryA);

  for (i = 0; i < 128; i++)
  {
    // check if leafs exist in both octrees
    ASSERT_EQ( octreeA.existLeaf(voxels[i].x,voxels[i].y,voxels[i].z), true);
    ASSERT_EQ( octreeB.existLeaf(voxels[i].x,voxels[i].y,voxels[i].z), true);
  }

  for (i = 128; i < 256; i++)
  {
    // these leafs were not copies and should not exist
    ASSERT_EQ( octreeB.existLeaf(voxels[i].x,voxels[i].y,voxels[i].z), false);
  }

  // testing deleteTree();
  octreeB.deleteTree ();

  // octreeB.getLeafCount() should be zero now;
  ASSERT_EQ (static_cast <unsigned int> (0), octreeB.getLeafCount());

  // .. and previous leafs deleted..
  for (i = 0; i < 128; i++)
  {
    ASSERT_EQ(octreeB.existLeaf(voxels[i].x,voxels[i].y,voxels[i].z), false);
  }

  // test tree serialization
  octreeA.serializeTree (treeBinaryA, leafVectorA);

  // make sure, we retrieved all data objects
  ASSERT_EQ(leafVectorA.size(), octreeA.getLeafCount());

  // check if leaf data is found in octree input data
  bool bFound;
  for (i = 0; i < 128; i++)
  {
    int leafInt = leafVectorA.back ();
    leafVectorA.pop_back ();

    bFound = false;
    for (j = 0; j < 256; j++)
      if (data[j] == leafInt)
      {
        bFound = true;
        break;
      }

    ASSERT_EQ(bFound, true);
  }

  // test tree serialization
  octreeA.serializeLeafs (leafVectorA);

  for (i = 0; i < 128; i++)
  {
    int leafInt = leafVectorA.back ();
    leafVectorA.pop_back ();

    bFound = false;
    for (j = 0; j < 256; j++)
      if (data[j] == leafInt)
      {
        bFound = true;
        break;
      }

    ASSERT_EQ(bFound, true);
  }

  // test tree serialization with leaf data vectors
  octreeA.serializeTree (treeBinaryA, leafVectorA);
  octreeB.deserializeTree (treeBinaryA, leafVectorA);

  // test size and leaf count of reconstructed octree
  ASSERT_EQ(octreeA.getLeafCount(), octreeB.getLeafCount());
  ASSERT_EQ(static_cast<unsigned int> (128), octreeB.getLeafCount());

  octreeB.serializeTree (treeBinaryB, leafVectorB);

  // compare octree data content of octree A and octree B
  ASSERT_EQ(leafVectorB.size(), octreeB.getLeafCount());
  ASSERT_EQ(leafVectorA.size(), leafVectorB.size());

  for (i = 0; i < leafVectorB.size (); i++)
  {
    ASSERT_EQ( (leafVectorA[i] == leafVectorB[i]), true);
  }

  //  test iterator

  OctreeBase<int>::Iterator a_it (octreeA);
  unsigned int node_count = 0;
  unsigned int branch_count = 0;
  unsigned int leaf_count = 0;

  // iterate over tree
  while (*++a_it)
  {
    // depth should always be less than tree depth
    unsigned int depth = a_it.getCurrentOctreeDepth ();
    ASSERT_LE(depth, octreeA.getTreeDepth());

    // store node, branch and leaf count
    const OctreeNode* node = a_it.getCurrentOctreeNode ();
    if (node->getNodeType () == BRANCH_NODE)
    {
      branch_count++;
    }
    else if (node->getNodeType () == LEAF_NODE)
    {
      leaf_count++;
    }
    node_count++;
  }

  // compare node, branch and leaf count against actual tree values
  ASSERT_EQ(node_count, branch_count + leaf_count);
  ASSERT_EQ(leaf_count, octreeA.getLeafCount ());

}

TEST (PCL, Octree_Dynamic_Depth_Test)
{

  size_t i;
  int test_runs = 100;
  int pointcount = 300;

  int test, point;

  float resolution = 0.01f;

  const static size_t leafAggSize = 5;

  OctreePointCloudPointVector<PointXYZ> octree (resolution);

  // create shared pointcloud instances
  PointCloud<PointXYZ>::Ptr cloud (new PointCloud<PointXYZ> ());

  // assign input point clouds to octree
  octree.setInputCloud (cloud);

  for (test = 0; test < test_runs; ++test)
  {

    // clean up
    cloud->points.clear ();
    octree.deleteTree ();

    for (point = 0; point < pointcount; point++)
    {
      // gereate a random point
      PointXYZ newPoint (static_cast<float> (1024.0 * rand () / RAND_MAX),
          static_cast<float> (1024.0 * rand () / RAND_MAX),
          static_cast<float> (1024.0 * rand () / RAND_MAX));

      // OctreePointCloudPointVector can store all points..
      cloud->push_back (newPoint);
    }

    // check if all points from leaf data can be found in input pointcloud data sets
    octree.defineBoundingBox ();
    octree.enableDynamicDepth (leafAggSize);
    octree.addPointsFromInputCloud ();

    //  test iterator
    OctreePointCloudPointVector<PointXYZ>::LeafNodeIterator it (octree);
    unsigned int leaf_count = 0;


    std::vector<int> indexVector;

    // iterate over tree
    while (*++it)
    {
      OctreeNode* node = it.getCurrentOctreeNode ();

      ASSERT_EQ(node->getNodeType(), LEAF_NODE);

      if (it.getCurrentOctreeDepth () < octree.getTreeDepth ())
        ASSERT_LE(it.getSize(), leafAggSize);

      // add points from leaf node to indexVector
      it.getData (indexVector);

      // test points against bounding box of leaf node
      std::vector<int> tmpVector;
      it.getData (tmpVector);

      Eigen::Vector3f min_pt, max_pt;
      octree.getVoxelBounds (it, min_pt, max_pt);

      for (i=0; i<tmpVector.size(); ++i)
      {
        ASSERT_GE(cloud->points[tmpVector[i]].x, min_pt(0));
        ASSERT_GE(cloud->points[tmpVector[i]].y, min_pt(1));
        ASSERT_GE(cloud->points[tmpVector[i]].z, min_pt(2));
        ASSERT_LE(cloud->points[tmpVector[i]].x, max_pt(0));
        ASSERT_LE(cloud->points[tmpVector[i]].y, max_pt(1));
        ASSERT_LE(cloud->points[tmpVector[i]].z, max_pt(2));
      }

      leaf_count++;

    }
    ASSERT_EQ(pointcount, indexVector.size());

    // make sure all indices are within indexVector
    for (i = 0; i < indexVector.size (); ++i)
    {
#if !defined(__APPLE__)
      bool indexFound = (std::find(indexVector.begin(), indexVector.end(), i) != indexVector.end());
      ASSERT_EQ(indexFound, true);
#endif
    }

    // compare node, branch and leaf count against actual tree values
    ASSERT_EQ(leaf_count, octree.getLeafCount ());

  }
}

TEST (PCL, Octree2Buf_Test)
{

  // create octree instances
  Octree2BufBase<int> octreeA;
  Octree2BufBase<int> octreeB;

  // set octree depth
  octreeA.setTreeDepth (8);
  octreeB.setTreeDepth (8);

  struct MyVoxel
  {
    unsigned int x;
    unsigned int y;
    unsigned int z;
  };

  unsigned int i, j;
  int data[256];
  MyVoxel voxels[256];

  srand (static_cast<unsigned int> (time (NULL)));

  // generate some voxel indices
  for (i = 0; i < 256; i++)
  {
    data[i] = i;

    voxels[i].x = i;
    voxels[i].y = 255 - i;
    voxels[i].z = i;

    // add data to leaf node voxel
    octreeA.addData (voxels[i].x, voxels[i].y, voxels[i].z, data[i]);

  }

  ASSERT_EQ(static_cast<unsigned int> (256), octreeA.getLeafCount());

  int TreeData;

  for (i = 0; i < 128; i++)
  {
    // retrieve and check data from leaf voxel
    octreeA.getData (voxels[i].x, voxels[i].y, voxels[i].z, TreeData);
    ASSERT_EQ(TreeData, data[i]);
  }

  for (i = 128; i < 256; i++)
  {
    // check if leaf node exists in tree
    ASSERT_EQ( octreeA.existLeaf(voxels[i].x,voxels[i].y,voxels[i].z), true);

    // remove leaf node
    octreeA.removeLeaf (voxels[i].x, voxels[i].y, voxels[i].z);

    //  leaf node shouldn't exist in tree anymore
    ASSERT_EQ( octreeA.existLeaf(voxels[i].x,voxels[i].y,voxels[i].z), false);
  }


  // test serialization

  std::vector<char> treeBinaryA;
  std::vector<char> treeBinaryB;

  std::vector<int> leafVectorA;
  std::vector<int> leafVectorB;

  // serialize tree - generate binary octree description
  octreeA.serializeTree (treeBinaryA);

  // deserialize tree - rebuild octree based on binary octree description
  octreeB.deserializeTree (treeBinaryA);

  // check if leafs exist in octrees
  for (i = 0; i < 128; i++)
  {
    ASSERT_EQ( octreeB.existLeaf(voxels[i].x,voxels[i].y,voxels[i].z), true);
  }

  // these leafs should not exist..
  for (i = 128; i < 256; i++)
  {
    ASSERT_EQ( octreeB.existLeaf(voxels[i].x,voxels[i].y,voxels[i].z), false);
  }

  // checking deleteTree();
  octreeB.deleteTree ();
  octreeB.setTreeDepth (8);

  // octreeB.getLeafCount() should be zero now;
  ASSERT_EQ(static_cast<unsigned int> (0), octreeB.getLeafCount());

  for (i = 0; i < 128; i++)
  {
    ASSERT_EQ( octreeB.existLeaf(voxels[i].x,voxels[i].y,voxels[i].z), false);
  }

  // test tree serialization
  octreeA.serializeTree (treeBinaryA, leafVectorA);

  // make sure, we retrieved all data objects
  ASSERT_EQ(leafVectorA.size(), octreeA.getLeafCount());

  // check if leaf data is found in octree input data
  bool bFound;
  for (i = 0; i < 128; i++)
  {
    int leafInt = leafVectorA.back ();
    leafVectorA.pop_back ();

    bFound = false;
    for (j = 0; j < 256; j++)
      if (data[j] == leafInt)
      {
        bFound = true;
        break;
      }

    ASSERT_EQ(bFound, true);
  }

  // test tree serialization
  octreeA.serializeLeafs (leafVectorA);

  for (i = 0; i < 128; i++)
  {
    int leafInt = leafVectorA.back ();
    leafVectorA.pop_back ();

    bFound = false;
    for (j = 0; j < 256; j++)
      if (data[j] == leafInt)
      {
        bFound = true;
        break;
      }

    ASSERT_EQ(bFound, true);
  }

  // test tree serialization with leaf data vectors
  octreeA.serializeTree (treeBinaryA, leafVectorA);
  octreeB.deserializeTree (treeBinaryA, leafVectorA);

  ASSERT_EQ(octreeA.getLeafCount(), octreeB.getLeafCount());
  ASSERT_EQ(static_cast<unsigned int> (128), octreeB.getLeafCount());

  octreeB.serializeTree (treeBinaryB, leafVectorB);

  // test size and leaf count of reconstructed octree
  ASSERT_EQ(leafVectorB.size(), octreeB.getLeafCount());
  ASSERT_EQ(leafVectorA.size(), leafVectorB.size());

  for (i = 0; i < leafVectorB.size (); i++)
  {
    ASSERT_EQ( (leafVectorA[i] == leafVectorB[i]), true);
  }

}


TEST (PCL, Octree2Buf_Base_Double_Buffering_Test)
{

#define TESTPOINTS 3000

  // create octree instances
  Octree2BufBase<int> octreeA;
  Octree2BufBase<int> octreeB;

  std::vector<char> treeBinaryA;
  std::vector<char> treeBinaryB;

  std::vector<int> leafVectorA;
  std::vector<int> leafVectorB;

  octreeA.setTreeDepth (5);
  octreeB.setTreeDepth (5);

  struct MyVoxel
  {
    unsigned int x;
    unsigned int y;
    unsigned int z;
  };

  unsigned int i, j, k, runs;
  int data[TESTPOINTS];
  MyVoxel voxels[TESTPOINTS];

  srand (static_cast<unsigned int> (time (NULL)));

  const unsigned int test_runs = 20;

  for (j = 0; j < test_runs; j++)
  {
    octreeA.deleteTree ();
    octreeB.deleteTree ();
    octreeA.setTreeDepth (5);
    octreeB.setTreeDepth (5);

    runs = rand () % 20 + 1;
    for (k = 0; k < runs; k++)
    {
      // switch buffers
      octreeA.switchBuffers ();
      octreeB.switchBuffers ();

      for (i = 0; i < TESTPOINTS; i++)
      {
        data[i] = rand ();

        voxels[i].x = rand () % 4096;
        voxels[i].y = rand () % 4096;
        voxels[i].z = rand () % 4096;

        // add data to octree

        octreeA.addData (voxels[i].x, voxels[i].y, voxels[i].z, data[i]);

      }

      // test serialization
      octreeA.serializeTree (treeBinaryA, leafVectorA, true);
      octreeB.deserializeTree (treeBinaryA, leafVectorA, true);
    }

    octreeB.serializeTree (treeBinaryB, leafVectorB, true);

    // check leaf count of rebuilt octree
    ASSERT_EQ(octreeA.getLeafCount(), octreeB.getLeafCount());
    ASSERT_EQ(leafVectorB.size(), octreeB.getLeafCount());
    ASSERT_EQ(leafVectorA.size(), leafVectorB.size());

    // check if octree octree structure is consistent.
    for (i = 0; i < leafVectorB.size (); i++)
    {
      ASSERT_EQ( (leafVectorA[i] == leafVectorB[i]), true);
    }

  }

}

TEST (PCL, Octree2Buf_Base_Double_Buffering_XOR_Test)
{

#define TESTPOINTS 3000

  // create octree instances
  Octree2BufBase<int> octreeA;
  Octree2BufBase<int> octreeB;

  std::vector<char> treeBinaryA;
  std::vector<char> treeBinaryB;

  std::vector<int> leafVectorA;
  std::vector<int> leafVectorB;

  octreeA.setTreeDepth (5);
  octreeB.setTreeDepth (5);

  struct MyVoxel
  {
    unsigned int x;
    unsigned int y;
    unsigned int z;
  };

  unsigned int i, j;
  int data[TESTPOINTS];
  MyVoxel voxels[TESTPOINTS];

  srand (static_cast<unsigned int> (time (NULL)));

  const unsigned int test_runs = 15;

  for (j = 0; j < test_runs; j++)
  {
    for (i = 0; i < TESTPOINTS; i++)
    {
      data[i] = rand ();

      voxels[i].x = rand () % 4096;
      voxels[i].y = rand () % 4096;
      voxels[i].z = rand () % 4096;

      // add data to octree

      octreeA.addData (voxels[i].x, voxels[i].y, voxels[i].z, data[i]);
    }

    // test serialization - XOR tree binary data
    octreeA.serializeTree (treeBinaryA, leafVectorA, true);
    octreeB.deserializeTree (treeBinaryA, leafVectorA, true);
    octreeB.serializeTree (treeBinaryB, leafVectorB, true);

    // check leaf count of rebuilt octree
    ASSERT_EQ(octreeA.getLeafCount(), octreeB.getLeafCount());
    ASSERT_EQ(leafVectorB.size(), octreeB.getLeafCount());
    ASSERT_EQ(leafVectorA.size(), leafVectorB.size());
    ASSERT_EQ(treeBinaryA.size(), octreeB.getBranchCount());
    ASSERT_EQ(treeBinaryA.size(), treeBinaryB.size());

    // check if octree octree structure is consistent.
    for (i = 0; i < leafVectorB.size (); i++)
    {
      ASSERT_EQ( (leafVectorA[i] == leafVectorB[i]), true);
    }

    // switch buffers
    octreeA.switchBuffers ();
    octreeB.switchBuffers ();

  }

}

TEST (PCL, Octree_Pointcloud_Test)
{

  size_t i;
  int test_runs = 100;
  int pointcount = 300;

  int test, point;

  float resolution = 0.01f;

  // instantiate OctreePointCloudSinglePoint and OctreePointCloudPointVector classes
  OctreePointCloudSinglePoint<PointXYZ> octreeA (resolution);
  OctreePointCloudSearch<PointXYZ> octreeB (resolution);
  OctreePointCloudPointVector<PointXYZ> octreeC (resolution);

  // create shared pointcloud instances
  PointCloud<PointXYZ>::Ptr cloudA (new PointCloud<PointXYZ> ());
  PointCloud<PointXYZ>::Ptr cloudB (new PointCloud<PointXYZ> ());

  // assign input point clouds to octree
  octreeA.setInputCloud (cloudA);
  octreeB.setInputCloud (cloudB);
  octreeC.setInputCloud (cloudB);

  for (test = 0; test < test_runs; ++test)
  {

    // clean up
    cloudA->points.clear ();
    octreeA.deleteTree ();

    cloudB->points.clear ();
    octreeB.deleteTree ();

    octreeC.deleteTree ();

    for (point = 0; point < pointcount; point++)
    {
      // gereate a random point
      PointXYZ newPoint (static_cast<float> (1024.0 * rand () / RAND_MAX), 
                         static_cast<float> (1024.0 * rand () / RAND_MAX), 
                         static_cast<float> (1024.0 * rand () / RAND_MAX));

      if (!octreeA.isVoxelOccupiedAtPoint (newPoint))
      {
        // add point only to OctreePointCloudSinglePoint if voxel at point location doesn't exist
        octreeA.addPointToCloud (newPoint, cloudA);
      }

      // OctreePointCloudPointVector can store all points..
      cloudB->push_back (newPoint);
    }

    ASSERT_EQ(octreeA.getLeafCount(), cloudA->points.size());

    // checks for getVoxelDataAtPoint() and isVoxelOccupiedAtPoint() functionality
    for (i = 0; i < cloudA->points.size (); i++)
    {
      ASSERT_EQ(octreeA.isVoxelOccupiedAtPoint(cloudA->points[i]), true);
      octreeA.deleteVoxelAtPoint (cloudA->points[i]);
      ASSERT_EQ(octreeA.isVoxelOccupiedAtPoint(cloudA->points[i]), false);
    }

    ASSERT_EQ(octreeA.getLeafCount(), static_cast<unsigned int> (0));

    // check if all points from leaf data can be found in input pointcloud data sets
    octreeB.defineBoundingBox ();
    octreeB.addPointsFromInputCloud ();

    //  test iterator
    OctreePointCloudSearch<PointXYZ>::Iterator b_it (octreeB);
    unsigned int node_count = 0;
    unsigned int branch_count = 0;
    unsigned int leaf_count = 0;

    double minx, miny, minz, maxx, maxy, maxz;
    octreeB.getBoundingBox (minx, miny, minz, maxx, maxy, maxz);

    // iterate over tree
    while (*++b_it)
    {
      // depth should always be less than tree depth
      unsigned int depth = b_it.getCurrentOctreeDepth ();
      ASSERT_LE(depth, octreeB.getTreeDepth());

      Eigen::Vector3f voxel_min, voxel_max;
      octreeB.getVoxelBounds (b_it, voxel_min, voxel_max);

      ASSERT_GE(voxel_min.x (), minx - 1e-4);
      ASSERT_GE(voxel_min.y (), miny - 1e-4);
      ASSERT_GE(voxel_min.z (), minz - 1e-4);

      ASSERT_LE(voxel_max.x (), maxx + 1e-4);
      ASSERT_LE(voxel_max.y (), maxy + 1e-4);
      ASSERT_LE(voxel_max.z (), maxz + 1e-4);

      // store node, branch and leaf count
      const OctreeNode* node = b_it.getCurrentOctreeNode ();
      if (node->getNodeType () == BRANCH_NODE)
      {
        branch_count++;
      }
      else if (node->getNodeType () == LEAF_NODE)
      {
        leaf_count++;
      }
      node_count++;
    }

    // compare node, branch and leaf count against actual tree values
    ASSERT_EQ(node_count, branch_count + leaf_count);
    ASSERT_EQ(leaf_count, octreeB.getLeafCount ());

    for (i = 0; i < cloudB->points.size (); i++)
    {

      std::vector<int> pointIdxVec;
      octreeB.voxelSearch (cloudB->points[i], pointIdxVec);

      bool bIdxFound = false;
      std::vector<int>::const_iterator current = pointIdxVec.begin ();
      while (current != pointIdxVec.end ())
      {
        if (*current == static_cast<int> (i))
        {
          bIdxFound = true;
          break;
        }
        ++current;
      }

      ASSERT_EQ(bIdxFound, true);

    }

    // test octree pointcloud serialization

    std::vector<char> treeBinaryB;
    std::vector<char> treeBinaryC;

    std::vector<int> leafVectorB;
    std::vector<int> leafVectorC;

    double minX, minY, minZ, maxX, maxY, maxZ;

    // serialize octreeB
    octreeB.serializeTree (treeBinaryB, leafVectorB);
    octreeB.getBoundingBox (minX, minY, minZ, maxX, maxY, maxZ);

    ASSERT_EQ(cloudB->points.size(), leafVectorB.size());

    // deserialize into octreeC
    octreeC.deleteTree ();
    octreeC.defineBoundingBox (minX, minY, minZ, maxX, maxY, maxZ);

    octreeC.deserializeTree (treeBinaryB, leafVectorB);

    // retrieve point data content of octreeC
    octreeC.serializeTree (treeBinaryC, leafVectorC);

    // check if data is consistent
    ASSERT_EQ(octreeB.getLeafCount(), octreeC.getLeafCount());
    ASSERT_EQ(treeBinaryB.size(), treeBinaryC.size());
    ASSERT_EQ(octreeB.getLeafCount(), cloudB->points.size());

    for (i = 0; i < leafVectorB.size (); ++i)
    {
      ASSERT_EQ(leafVectorB[i], leafVectorC[i]);
    }

    // check if binary octree output of both trees is equal
    for (i = 0; i < treeBinaryB.size (); ++i)
    {
      ASSERT_EQ(treeBinaryB[i], treeBinaryC[i]);
    }

  }

}

TEST (PCL, Octree_Pointcloud_Density_Test)
{

  // instantiate point cloud and fill it with point data

  PointCloud<PointXYZ>::Ptr cloudIn (new PointCloud<PointXYZ> ());

  for (float z = 0.05f; z < 7.0f; z += 0.1f)
    for (float y = 0.05f; y < 7.0f; y += 0.1f)
      for (float x = 0.05f; x < 7.0f; x += 0.1f)
        cloudIn->push_back (PointXYZ (x, y, z));

  cloudIn->width = static_cast<uint32_t> (cloudIn->points.size ());
  cloudIn->height = 1;

  OctreePointCloudDensity<PointXYZ> octreeA (1.0f); // low resolution
  OctreePointCloudDensity<PointXYZ> octreeB (0.00001f); // high resolution

  octreeA.defineBoundingBox (7.0, 7.0, 7.0);
  octreeB.defineBoundingBox (7.0, 7.0, 7.0);

  // add point data to octree
  octreeA.setInputCloud (cloudIn);
  octreeB.setInputCloud (cloudIn);

  octreeA.addPointsFromInputCloud ();
  octreeB.addPointsFromInputCloud ();

  // check density information
  for (float z = 1.5f; z < 3.5f; z += 1.0f)
    for (float y = 1.5f; y < 3.5f; y += 1.0f)
      for (float x = 1.5f; x < 3.5f; x += 1.0f)
        ASSERT_EQ(octreeA.getVoxelDensityAtPoint (PointXYZ(x, y, z)), static_cast<unsigned int> (1000));

  for (float z = 0.05f; z < 5.0f; z += 0.1f)
    for (float y = 0.05f; y < 5.0f; y += 0.1f)
      for (float x = 0.05f; x < 5.0f; x += 0.1f)
        ASSERT_EQ(octreeB.getVoxelDensityAtPoint (PointXYZ(x, y, z)), static_cast<unsigned int> (1));
}

TEST (PCL, Octree_Pointcloud_Iterator_Test)
{
  // instantiate point cloud and fill it with point data

  PointCloud<PointXYZ>::Ptr cloudIn (new PointCloud<PointXYZ> ());

  for (float z = 0.05f; z < 7.0f; z += 0.1f)
    for (float y = 0.05f; y < 7.0f; y += 0.1f)
      for (float x = 0.05f; x < 7.0f; x += 0.1f)
        cloudIn->push_back (PointXYZ (x, y, z));

  cloudIn->width = static_cast<uint32_t> (cloudIn->points.size ());
  cloudIn->height = 1;

  OctreePointCloud<PointXYZ> octreeA (1.0f); // low resolution

  // add point data to octree
  octreeA.setInputCloud (cloudIn);
  octreeA.addPointsFromInputCloud ();

  // instantiate iterator for octreeA
  OctreePointCloud<PointXYZ>::LeafNodeIterator it1 (octreeA);

  std::vector<int> indexVector;
  unsigned int leafNodeCounter = 0;

  // test preincrement
  ++it1;
  it1.getData (indexVector);
  leafNodeCounter++;

  // test postincrement
  it1++;
  it1.getData (indexVector);
  leafNodeCounter++;

  while (*++it1)
  {
    it1.getData (indexVector);
    leafNodeCounter++;
  }

  ASSERT_EQ(indexVector.size(), cloudIn->points.size ());
  ASSERT_EQ(leafNodeCounter, octreeA.getLeafCount());

  OctreePointCloud<PointXYZ>::Iterator it2 (octreeA);

  unsigned int traversCounter = 0;
  while (*++it2)
  {
    traversCounter++;
  }

  ASSERT_EQ(traversCounter > octreeA.getLeafCount() + octreeA.getBranchCount(), true);

  // breadth-first iterator test

  OctreePointCloud<PointXYZ>::BreadthFirstIterator bfIt (octreeA);

  unsigned int lastDepth = 0;
  unsigned int branchNodeCount = 1;
  unsigned int leafNodeCount = 0;

  bool leafNodeVisited = false;

  while (*++bfIt)
  {
    // tree depth of visited nodes must grow
    ASSERT_EQ( bfIt.getCurrentOctreeDepth()>=lastDepth, true);
    lastDepth = bfIt.getCurrentOctreeDepth ();

    if (bfIt.isBranchNode ())
    {
      branchNodeCount++;
      // leaf nodes are traversed in the end
      ASSERT_EQ( leafNodeVisited, false);
    }

    if (bfIt.isLeafNode ())
    {
      leafNodeCount++;
      leafNodeVisited = true;
    }
  }

  // check if every branch node and every leaf node has been visited
  ASSERT_EQ( leafNodeCount, octreeA.getLeafCount());
  ASSERT_EQ( branchNodeCount, octreeA.getBranchCount());

}

TEST(PCL, Octree_Pointcloud_Occupancy_Test)
{
  const unsigned int test_runs = 100;
  unsigned int test_id;

  // instantiate point cloud

  PointCloud<PointXYZ>::Ptr cloudIn (new PointCloud<PointXYZ> ());

  OctreePointCloudOccupancy<PointXYZ> octree (0.00001f);

  size_t i;

  srand (static_cast<unsigned int> (time (NULL)));

  for (test_id = 0; test_id < test_runs; test_id++)
  {

    cloudIn->width = 1000;
    cloudIn->height = 1;
    cloudIn->points.resize (cloudIn->width * cloudIn->height);

    // generate point data for point cloud
    for (i = 0; i < 1000; i++)
    {
      cloudIn->points[i] = PointXYZ (static_cast<float> (5.0  * rand () / RAND_MAX),
                                     static_cast<float> (10.0 * rand () / RAND_MAX),
                                     static_cast<float> (10.0 * rand () / RAND_MAX));
    }

    // create octree
    octree.setInputCloud (cloudIn);
    octree.addPointsFromInputCloud ();

    // check occupancy of voxels
    for (i = 0; i < 1000; i++)
    {
      ASSERT_EQ(octree.isVoxelOccupiedAtPoint(cloudIn->points[i]), true);
      octree.deleteVoxelAtPoint (cloudIn->points[i]);
      ASSERT_EQ(octree.isVoxelOccupiedAtPoint(cloudIn->points[i]), false);
    }

  }

}

TEST (PCL, Octree_Pointcloud_Change_Detector_Test)
{
  // instantiate point cloud

  PointCloud<PointXYZ>::Ptr cloudIn (new PointCloud<PointXYZ> ());

  OctreePointCloudChangeDetector<PointXYZ> octree (0.01f);

  size_t i;

  srand (static_cast<unsigned int> (time (NULL)));

  cloudIn->width = 1000;
  cloudIn->height = 1;
  cloudIn->points.resize (cloudIn->width * cloudIn->height);

  // generate point data for point cloud
  for (i = 0; i < 1000; i++)
  {
    cloudIn->points[i] = PointXYZ (static_cast<float> (5.0  * rand () / RAND_MAX),
                                   static_cast<float> (10.0 * rand () / RAND_MAX),
                                   static_cast<float> (10.0 * rand () / RAND_MAX));
  }

  // assign point cloud to octree
  octree.setInputCloud (cloudIn);

  // add points from cloud to octree
  octree.addPointsFromInputCloud ();

  // switch buffers - reset tree
  octree.switchBuffers ();

  // add points from cloud to new octree buffer
  octree.addPointsFromInputCloud ();

  // add 1000 additional points
  for (i = 0; i < 1000; i++)
  {
    octree.addPointToCloud (
        PointXYZ (static_cast<float> (100.0 + 5.0  * rand () / RAND_MAX), 
                  static_cast<float> (100.0 + 10.0 * rand () / RAND_MAX),
                  static_cast<float> (100.0 + 10.0 * rand () / RAND_MAX)),
        cloudIn);
  }

  vector<int> newPointIdxVector;

  // get a vector of new points, which did not exist in previous buffer
  octree.getPointIndicesFromNewVoxels (newPointIdxVector);

  // should be 1000
  ASSERT_EQ( newPointIdxVector.size(), static_cast<std::size_t> (1000));

  // all point indices found should have an index of >= 1000
  for (i = 0; i < 1000; i++)
  {
    ASSERT_EQ( ( newPointIdxVector [i] >= 1000 ), true);
  }

}

TEST (PCL, Octree_Pointcloud_Voxel_Centroid_Test)
{

  // instantiate point cloud

  PointCloud<PointXYZ>::Ptr cloudIn (new PointCloud<PointXYZ> ());

  OctreePointCloudVoxelCentroid<PointXYZ> octree (1.0f);
  octree.defineBoundingBox (10.0, 10.0, 10.0);

  size_t i;

  srand (static_cast<unsigned int> (time (NULL)));

  cloudIn->width = 10 * 3;
  cloudIn->height = 1;
  cloudIn->points.resize (cloudIn->width * cloudIn->height);

  // generate point data for point cloud
  for (i = 0; i < 10; i++)
  {
    // these three points should always be assigned to the same voxel in the octree
    cloudIn->points[i * 3 + 0] = PointXYZ (static_cast<float> (i) + 0.2f, static_cast<float> (i) + 0.2f, static_cast<float> (i) + 0.2f);
    cloudIn->points[i * 3 + 1] = PointXYZ (static_cast<float> (i) + 0.4f, static_cast<float> (i) + 0.4f, static_cast<float> (i) + 0.4f);
    cloudIn->points[i * 3 + 2] = PointXYZ (static_cast<float> (i) + 0.6f, static_cast<float> (i) + 0.6f, static_cast<float> (i) + 0.6f);
  }

  // assign point cloud to octree
  octree.setInputCloud (cloudIn);

  // add points from cloud to octree
  octree.addPointsFromInputCloud ();

  pcl::PointCloud<PointXYZ>::VectorType voxelCentroids;
  octree.getVoxelCentroids (voxelCentroids);

  // we expect 10 voxel centroids
  ASSERT_EQ (voxelCentroids.size(), static_cast<std::size_t> (10));

  // check centroid calculation
  for (i = 0; i < 10; i++)
  {
    EXPECT_NEAR(voxelCentroids[i].x, static_cast<float> (i)+0.4, 1e-4);
    EXPECT_NEAR(voxelCentroids[i].y, static_cast<float> (i)+0.4, 1e-4);
    EXPECT_NEAR(voxelCentroids[i].z, static_cast<float> (i)+0.4, 1e-4);
  }

}

// helper class for priority queue
class prioPointQueueEntry
{
public:
  prioPointQueueEntry () : point_ (), pointDistance_ (), pointIdx_ ()
  {
  }
  prioPointQueueEntry (PointXYZ& point_arg, double pointDistance_arg, int pointIdx_arg) :
    point_ (point_arg),
    pointDistance_ (pointDistance_arg),
    pointIdx_ (pointIdx_arg)
  {
  }

  bool
  operator< (const prioPointQueueEntry& rhs_arg) const
  {
    return (this->pointDistance_ < rhs_arg.pointDistance_);
  }

  PointXYZ point_;
  double pointDistance_;
  int pointIdx_;

};

TEST (PCL, Octree_Pointcloud_Nearest_K_Neighbour_Search)
{

  const unsigned int test_runs = 10;
  unsigned int test_id;

  // instantiate point cloud
  PointCloud<PointXYZ>::Ptr cloudIn (new PointCloud<PointXYZ> ());

  size_t i;

  srand (static_cast<unsigned int> (time (NULL)));

  unsigned int K;

  std::priority_queue<prioPointQueueEntry, pcl::PointCloud<prioPointQueueEntry>::VectorType> pointCandidates;

  // create octree
  OctreePointCloudSearch<PointXYZ> octree (0.1);
  octree.setInputCloud (cloudIn);

  std::vector<int> k_indices;
  std::vector<float> k_sqr_distances;

  std::vector<int> k_indices_bruteforce;
  std::vector<float> k_sqr_distances_bruteforce;

  for (test_id = 0; test_id < test_runs; test_id++)
  {
    // define a random search point

    PointXYZ searchPoint (static_cast<float> (10.0 * rand () / RAND_MAX), 
                          static_cast<float> (10.0 * rand () / RAND_MAX),
                          static_cast<float> (10.0 * rand () / RAND_MAX));

    K = 1 + rand () % 10;

    // generate point cloud
    cloudIn->width = 1000;
    cloudIn->height = 1;
    cloudIn->points.resize (cloudIn->width * cloudIn->height);
    for (i = 0; i < 1000; i++)
    {
      cloudIn->points[i] = PointXYZ (static_cast<float> (5.0  * rand () / RAND_MAX),
                                     static_cast<float> (10.0 * rand () / RAND_MAX),
                                     static_cast<float> (10.0 * rand () / RAND_MAX));
    }

    double pointDist;

    k_indices.clear ();
    k_sqr_distances.clear ();

    k_indices_bruteforce.clear ();
    k_sqr_distances_bruteforce.clear ();

    // push all points and their distance to the search point into a priority queue - bruteforce approach.
    for (i = 0; i < cloudIn->points.size (); i++)
    {
      pointDist = ((cloudIn->points[i].x - searchPoint.x) * (cloudIn->points[i].x - searchPoint.x)
          + (cloudIn->points[i].y - searchPoint.y) * (cloudIn->points[i].y - searchPoint.y)
          + (cloudIn->points[i].z - searchPoint.z) * (cloudIn->points[i].z - searchPoint.z));

      prioPointQueueEntry pointEntry (cloudIn->points[i], pointDist, static_cast<int> (i));

      pointCandidates.push (pointEntry);
    }

    // pop priority queue until we have the nearest K elements
    while (pointCandidates.size () > K)
      pointCandidates.pop ();

    // copy results into vectors
    unsigned idx = static_cast<unsigned> (pointCandidates.size ());
    k_indices_bruteforce.resize (idx);
    k_sqr_distances_bruteforce.resize (idx);
    while (pointCandidates.size ())
    {
      --idx;
      k_indices_bruteforce [idx] = pointCandidates.top ().pointIdx_;
      k_sqr_distances_bruteforce [idx] = static_cast<float> (pointCandidates.top ().pointDistance_);

      pointCandidates.pop ();
    }
    
    // octree nearest neighbor search
    octree.deleteTree ();
    octree.addPointsFromInputCloud ();
    octree.nearestKSearch (searchPoint, static_cast<int> (K), k_indices, k_sqr_distances);

    ASSERT_EQ( k_indices.size(), k_indices_bruteforce.size());

    // compare nearest neighbor results of octree with bruteforce search
    i = 0;
    while (k_indices_bruteforce.size ())
    {
      ASSERT_EQ( k_indices.back(), k_indices_bruteforce.back());
      EXPECT_NEAR(k_sqr_distances.back(), k_sqr_distances_bruteforce.back(), 1e-4);

      k_indices_bruteforce.pop_back ();
      k_indices.pop_back ();

      k_sqr_distances_bruteforce.pop_back ();
      k_sqr_distances.pop_back ();

    }

  }

}

TEST (PCL, Octree_Pointcloud_Box_Search)
{

  const unsigned int test_runs = 30;
  unsigned int test_id;

  // instantiate point cloud
  PointCloud<PointXYZ>::Ptr cloudIn (new PointCloud<PointXYZ> ());

  size_t i;

  srand (static_cast<unsigned int> (time (NULL)));

  // create octree
  OctreePointCloudSearch<PointXYZ> octree (1);
  octree.setInputCloud (cloudIn);

  for (test_id = 0; test_id < test_runs; test_id++)
  {
    std::vector<int> k_indices;

    // generate point cloud
    cloudIn->width = 300;
    cloudIn->height = 1;
    cloudIn->points.resize (cloudIn->width * cloudIn->height);
    for (i = 0; i < cloudIn->points.size(); i++)
    {
      cloudIn->points[i] = PointXYZ (static_cast<float> (10.0 * rand () / RAND_MAX),
                                     static_cast<float> (10.0 * rand () / RAND_MAX),
                                     static_cast<float> (10.0 * rand () / RAND_MAX));
    }


    // octree points to octree
    octree.deleteTree ();
    octree.addPointsFromInputCloud ();

    // define a random search area

    Eigen::Vector3f lowerBoxCorner (static_cast<float> (4.0 * rand () / RAND_MAX),
                                    static_cast<float> (4.0 * rand () / RAND_MAX),
                                    static_cast<float> (4.0 * rand () / RAND_MAX));
    Eigen::Vector3f upperBoxCorner (static_cast<float> (5.0 + 4.0 * rand () / RAND_MAX),
                                    static_cast<float> (5.0 + 4.0 * rand () / RAND_MAX),
                                    static_cast<float> (5.0 + 4.0 * rand () / RAND_MAX));

    octree.boxSearch (lowerBoxCorner, upperBoxCorner, k_indices);

    // test every point in point cloud
    for (i = 0; i < 300; i++)
    {
      std::size_t j;
      bool inBox;
      bool idxInResults;
      const PointXYZ& pt = cloudIn->points[i];

      inBox = (pt.x > lowerBoxCorner (0)) && (pt.x < upperBoxCorner (0)) &&
              (pt.y > lowerBoxCorner (1)) && (pt.y < upperBoxCorner (1)) &&
              (pt.z > lowerBoxCorner (2)) && (pt.z < upperBoxCorner (2));

      idxInResults = false;
      for (j = 0; (j < k_indices.size ()) && (!idxInResults); ++j)
      {
        if (i == static_cast<unsigned int> (k_indices[j]))
          idxInResults = true;
      }

      ASSERT_EQ(idxInResults, inBox);

    }

  }
}

TEST(PCL, Octree_Pointcloud_Approx_Nearest_Neighbour_Search)
{
  const unsigned int test_runs = 100;
  unsigned int test_id;

  unsigned int bestMatchCount = 0;

  // instantiate point cloud
  PointCloud<PointXYZ>::Ptr cloudIn (new PointCloud<PointXYZ> ());

  size_t i;
  srand (static_cast<unsigned int> (time (NULL)));

  double voxelResolution = 0.1;

  // create octree
  OctreePointCloudSearch<PointXYZ> octree (voxelResolution);
  octree.setInputCloud (cloudIn);

  for (test_id = 0; test_id < test_runs; test_id++)
  {
    // define a random search point

    PointXYZ searchPoint (static_cast<float> (10.0 * rand () / RAND_MAX), 
                          static_cast<float> (10.0 * rand () / RAND_MAX),
                          static_cast<float> (10.0 * rand () / RAND_MAX));

    // generate point cloud
    cloudIn->width = 1000;
    cloudIn->height = 1;
    cloudIn->points.resize (cloudIn->width * cloudIn->height);
    for (i = 0; i < 1000; i++)
    {
      cloudIn->points[i] = PointXYZ (static_cast<float> (5.0  * rand () / RAND_MAX),
                                     static_cast<float> (10.0 * rand () / RAND_MAX),
                                     static_cast<float> (10.0 * rand () / RAND_MAX));
    }

    // brute force search
    double pointDist;
    double BFdistance = numeric_limits<double>::max ();
    int BFindex = 0;

    for (i = 0; i < cloudIn->points.size (); i++)
    {
      pointDist = ((cloudIn->points[i].x - searchPoint.x) * (cloudIn->points[i].x - searchPoint.x)
          + (cloudIn->points[i].y - searchPoint.y) * (cloudIn->points[i].y - searchPoint.y)
          + (cloudIn->points[i].z - searchPoint.z) * (cloudIn->points[i].z - searchPoint.z));

      if (pointDist < BFdistance)
      {
        BFindex = static_cast<int> (i);
        BFdistance = pointDist;
      }

    }

    int ANNindex;
    float ANNdistance;

    // octree approx. nearest neighbor search
    octree.deleteTree ();
    octree.addPointsFromInputCloud ();
    octree.approxNearestSearch (searchPoint, ANNindex, ANNdistance);

    if (BFindex == ANNindex)
    {
      EXPECT_NEAR(ANNdistance, BFdistance, 1e-4);
      bestMatchCount++;
    }

  }

  // we should have found the absolute nearest neighbor at least once
  ASSERT_EQ( (bestMatchCount > 0), true);

}

TEST (PCL, Octree_Pointcloud_Neighbours_Within_Radius_Search)
{

  const unsigned int test_runs = 100;
  unsigned int test_id;

  // instantiate point clouds
  PointCloud<PointXYZ>::Ptr cloudIn (new PointCloud<PointXYZ> ());
  PointCloud<PointXYZ>::Ptr cloudOut (new PointCloud<PointXYZ> ());

  size_t i;

  srand (static_cast<unsigned int> (time (NULL)));

  for (test_id = 0; test_id < test_runs; test_id++)
  {
    // define a random search point
    PointXYZ searchPoint (static_cast<float> (10.0 * rand () / RAND_MAX), 
                          static_cast<float> (10.0 * rand () / RAND_MAX),
                          static_cast<float> (10.0 * rand () / RAND_MAX));

    cloudIn->width = 1000;
    cloudIn->height = 1;
    cloudIn->points.resize (cloudIn->width * cloudIn->height);

    // generate point cloud data
    for (i = 0; i < 1000; i++)
    {
      cloudIn->points[i] = PointXYZ (static_cast<float> (10.0 * rand () / RAND_MAX),
                                     static_cast<float> (10.0 * rand () / RAND_MAX),
                                     static_cast<float> (5.0  * rand () / RAND_MAX));
    }

    OctreePointCloudSearch<PointXYZ> octree (0.001);

    // build octree
    octree.setInputCloud (cloudIn);
    octree.addPointsFromInputCloud ();

    double pointDist;
    double searchRadius = 5.0 * static_cast<float> (rand () / RAND_MAX);

    // bruteforce radius search
    vector<int> cloudSearchBruteforce;
    for (i = 0; i < cloudIn->points.size (); i++)
    {
      pointDist = sqrt (
          (cloudIn->points[i].x - searchPoint.x) * (cloudIn->points[i].x - searchPoint.x)
              + (cloudIn->points[i].y - searchPoint.y) * (cloudIn->points[i].y - searchPoint.y)
              + (cloudIn->points[i].z - searchPoint.z) * (cloudIn->points[i].z - searchPoint.z));

      if (pointDist <= searchRadius)
      {
        // add point candidates to vector list
        cloudSearchBruteforce.push_back (static_cast<int> (i));
      }
    }

    vector<int> cloudNWRSearch;
    vector<float> cloudNWRRadius;

    // execute octree radius search
    octree.radiusSearch (searchPoint, searchRadius, cloudNWRSearch, cloudNWRRadius);

    ASSERT_EQ( cloudNWRRadius.size(), cloudSearchBruteforce.size());

    // check if result from octree radius search can be also found in bruteforce search
    std::vector<int>::const_iterator current = cloudNWRSearch.begin ();
    while (current != cloudNWRSearch.end ())
    {
      pointDist = sqrt (
          (cloudIn->points[*current].x - searchPoint.x) * (cloudIn->points[*current].x - searchPoint.x)
              + (cloudIn->points[*current].y - searchPoint.y) * (cloudIn->points[*current].y - searchPoint.y)
              + (cloudIn->points[*current].z - searchPoint.z) * (cloudIn->points[*current].z - searchPoint.z));

      ASSERT_EQ( (pointDist<=searchRadius), true);

      ++current;
    }

    // check if result limitation works
    octree.radiusSearch (searchPoint, searchRadius, cloudNWRSearch, cloudNWRRadius, 5);

    ASSERT_EQ( cloudNWRRadius.size() <= 5, true);

  }

}

TEST (PCL, Octree_Pointcloud_Ray_Traversal)
{

  const unsigned int test_runs = 100;
  unsigned int test_id;

  // instantiate point clouds
  PointCloud<PointXYZ>::Ptr cloudIn (new PointCloud<PointXYZ> ());

  octree::OctreePointCloudSearch<PointXYZ> octree_search (0.02f);

  // Voxels in ray
  pcl::PointCloud<pcl::PointXYZ>::VectorType voxelsInRay, voxelsInRay2;

  // Indices in ray
  std::vector<int> indicesInRay, indicesInRay2;

  srand (static_cast<unsigned int> (time (NULL)));

  for (test_id = 0; test_id < test_runs; test_id++)
  {
    // delete octree
    octree_search.deleteTree ();
    // define octree bounding box 10x10x10
    octree_search.defineBoundingBox (0.0, 0.0, 0.0, 10.0, 10.0, 10.0);

    cloudIn->width = 4;
    cloudIn->height = 1;
    cloudIn->points.resize (cloudIn->width * cloudIn->height);

    Eigen::Vector3f p (static_cast<float> (10.0 * rand () / RAND_MAX), 
                       static_cast<float> (10.0 * rand () / RAND_MAX),
                       static_cast<float> (10.0 * rand () / RAND_MAX));

    // origin
    Eigen::Vector3f o (static_cast<float> (12.0 * rand () / RAND_MAX), 
                       static_cast<float> (12.0 * rand () / RAND_MAX),
                       static_cast<float> (12.0 * rand () / RAND_MAX));

    cloudIn->points[0] = pcl::PointXYZ (p[0], p[1], p[2]);

    // direction vector
    Eigen::Vector3f dir (p - o);

    float tmin = 1.0;
    for (unsigned int j = 1; j < 4; j++)
    {
      tmin = tmin - 0.25f;
      Eigen::Vector3f n_p = o + (tmin * dir);
      cloudIn->points[j] = pcl::PointXYZ (n_p[0], n_p[1], n_p[2]);
    }

    // insert cloud point into octree
    octree_search.setInputCloud (cloudIn);
    octree_search.addPointsFromInputCloud ();

    octree_search.getIntersectedVoxelCenters (o, dir, voxelsInRay);
    octree_search.getIntersectedVoxelIndices (o, dir, indicesInRay);

    // check if all voxels in the cloud are penetraded by the ray
    ASSERT_EQ( voxelsInRay.size (), cloudIn->points.size ());
    // check if all indices of penetrated voxels are in cloud
    ASSERT_EQ( indicesInRay.size (), cloudIn->points.size ());

    octree_search.getIntersectedVoxelCenters (o, dir, voxelsInRay2, 1);
    octree_search.getIntersectedVoxelIndices (o, dir, indicesInRay2, 1);

    // check if only the point from a single voxel has been returned
    ASSERT_EQ( voxelsInRay2.size (), 1u );
    ASSERT_EQ( indicesInRay2.size (), 1u );

    // check if this point is the closest point to the origin
    pcl::PointXYZ pt = cloudIn->points[ indicesInRay2[0] ];
    Eigen::Vector3f d = Eigen::Vector3f (pt.x, pt.y, pt.z) - o;
    float min_dist = d.norm ();

    for (unsigned int i = 0; i < cloudIn->width * cloudIn->height; i++) {
        pt = cloudIn->points[i];
        d = Eigen::Vector3f (pt.x, pt.y, pt.z) - o;
        ASSERT_GE( d.norm (), min_dist );
    }

  }

}

/* ---[ */
int
main (int argc, char** argv)
{
  testing::InitGoogleTest (&argc, argv);
  return (RUN_ALL_TESTS ());
}
/* ]--- */