Visualizing the 3D Map as a PointCloud while building.

[conorjmcq]

Hi there,

I'm relatively new to using RTABMAP, but I have extensive background in using SLAM to create 3D scans with an Intel Realsense camera.

My question is simple, the default viewer while you're running RTABMAP shows the 3D scene as it's being built, but is there a method that I'm missing or a tutorial that shows how to display that map as a set of points ?

I'm researching for a college project and would like to add my own visualisations to the scene but this can only be done if they were rendered as x, y, z points.

Thank you for your help and effort.

Conor.

[conorjmcq]

Furthermore, I would like to be able to use an Oculus Rift headset in order to sit in some x, y, z position in the scene and look around as the camera is moving. 'This really being my end goal'.

I have done this before using a pre-built ply file but would like to try it as the slam algorithm is running.

[matlabbe]

Hi,

Rtabmap interface shows already the point cloud of the map, not sure what do you mean by "how to display that map as a set of points". If you want a single merged point cloud, look at the ros package (rtabmap_ros) and subscribe to /rtabmap/cloud_map topic. It is still preferred to subscribe to /rtabmap/mapData and reconstruct the cloud on your side (with point cloud density you want), but "/rtabmap/cloud_map" can be a good start.

For the standalone library, there is a c++ example here reconstructing the cloud from rtabmap events.

cheers,
Mathieu

[conorjmcq]

Hi Mathieu,

Thank you very much for the swift reply. I wasn't very clear before.

My current method for setting up an Oculus headset using the Ogre library only allows me to view the points I draw from my camera when they are declared by their x y and z coordinates as I draw using vertices.

I was just wondering if there was an easy access into how RTABMAP displays it's points that would allow me to setup Oculus in a similar manner.

I will check out the links you've shared. Thank you very much !

Conor.

[matlabbe]

Hi Conor,

The rviz plugin of rtabmap is converting rtabmap data to a point cloud for Ogre. See the code here.
Therefore the code could be a mix of the RGBD example linked in my previous post and this code.

cheers,
Mathieu