What kind of cloud processing do you want to do? Generation of the point clouds are done in the GUI only for vizualization purpose. The data kept for actual SLAM are raw RGB and depth 2D images. For example, when we show a point cloud in the 3D Map view, the point cloud is generated using this method
MainWindow::createCloud(). For the actual method creating a point cloud from RGB and depth images acquired from a
CameraRGBD object, see
util3d::cloudFromDepthRGB().
Cloud processing on these created clouds won't affect the SLAM system.
rtabmap/tools/CameraRGBD is a simple application called "rtabmap-rgbd_camera" to show RGB and depth images as well as creating a point cloud to show.