I am using the rtabmap-export to save ply files, but the normals of the ground seem to be downwards. My problem with this is that I need to convert the file to .glb, and my glb visualizer only gives textures to the side of the normal vector, so if I look at the map from above I can't see any color because it is on the down side. I attach images to clarify it: in the first image the floor is invisible, but in the second one the point of view is down the floor and the color appears.
I have found why it is happening, the poses are being saved under the floor, so the map is being created avobe the pose and the normals are computed downwards. I'm researching to find why are the poses under the floor of the map.
I add the rviz result, where the map is over the z=0 plane.
Is this on a robot? maybe the frame_id used by rtabmap is not the one on the floor, or the TF between the base and the camera is wrong (not matching the reality). With rtabmap-export, the normals are adjusted depending on the point of view of the camera.