... source : https://github.com/OctoMap/octomap_mapping

Go trough this pdf once to get an understanding of octomap with ros octomap_ros tutorial

If you have a pcd file

1.you need to remap the output topic cloud_pcd to cloud_in because octomap package subscribes to cloud_in <BR/> 2.create a launch folder in pcl_ros and create a file named pcd_to_pcl.launch, copy the following code to your launch file.

<launch>
        
    <node pkg="pcl_ros" type="pcd_to_pointcloud" name="spawn_pcd_to_pcl" output="screen" args ="path-to-you-pcd-file/cloud_in.pcd 0.1" >

    <param name="frame_id" value="/map" />
    <remap from="cloud_pcd" to="cloud_in" />
    </node>
</launch>

2.Run the launch file

roslaunch pcl_ros pcd_to_pcl.launch

3.start your octomap node as below

rosrun octomap_server octomap_tracking_server_node

4.start rviz and add the topic: /occupied_cells_vis_array to visualize octomap cells

rosrun rviz rviz

5.save octotree

rosrun octomap_server octomap_saver -f mapfile.ot

6.Install octovis to visualize the ot or bt file

sudo apt-get install ros-indigo-octovis

7. to visualize your saved ot or bt file

octovis yourfilename

8.for distance transform in 3D with octomap need to install dynamic-edt-3d, a seperate package

sudo apt-get install ros-indigo-dynamic-edt-3d

9.Worst part is in my version it doesnot have config file to link the libraries and it is only there as debian, so i only can install with apt-get. Package is not available for build from source issue link

set(DYNAMICEDT3D_LIBRARIES "/opt/ros/indigo/lib/libdynamicedt3d.so")
include_directories(
  include
  ${catkin_INCLUDE_DIRS}
  ${PCL_INCLUDE_DIRS}
  ${OCTOMAP_INCLUDE_DIRS}
  ${DYNAMICEDT3D_LIBRARIES}
)

if you check the above box, i have added DYNAMICEDT3D_LIBRARIES variable to the path of the library in the CMakeLists.txt 10. for changing the resolution, change the octo_mapping.launch file

<launch>
        <node pkg="octomap_server" type="octomap_server_node" name="octomap_server">
                <param name="resolution" value="0.5" />
                
                <!--common frame id fixed map frame (set to 'map' if SLAM or localization running!) -->
                <param name="frame_id" type="string" value="map" />
                
                <!-- maximum range to integrate (speedup!) -->
                <param name="sensor_model/max_range" value="5.0" />
                
                <!-- data source to integrate (PointCloud2) -->
                <!--remap from="cloud_in" to="/narrow_stereo/points_filtered2" /-->
        
        </node>
</launch>

roslaunch octomap_server octomap_mapping.launch