1. A method performed by a computer system comprising processor electronics and at least one memory device, the method comprising: capturing three dimensional (3D) point clouds using a 3D camera, each of the 3D point clouds corresponding to a different relative position of the 3D camera with respect to a body; setting one of the 3D point clouds as a reference point cloud; determining transforms for coordinates of the captured 3D point clouds, other than the reference point cloud, to transform to coordinates of the reference point cloud; segmenting the body represented in the reference point cloud into body parts corresponding to elements of a 3D part-based volumetric model comprising cylindrical representations; and generating a segmented representation of the physical object of interest in accordance with the 3D part-based volumetric model, wherein the generating comprises, for each of the captured 3D point clouds other than the reference point cloud, transforming the captured 3D point cloud using its transform, segmenting the body represented in the transformed 3D point cloud using the body parts corresponding to the elements of the 3D part-based volumetric model, and determining local motion, for each of the body parts corresponding to the elements of the 3D part-based volumetric model, between the transformed 3D point cloud and the reference point cloud; wherein a junction between at least two of the cylindrical representations, which are processed as unwrapped cylindrical maps, is handled by setting a first of the cylindrical maps as a reference map, transforming points of a second of the cylindrical maps to the reference map, and blending the transformed points of the second of the cylindrical maps with points of the first of the cylindrical maps to smooth the junction.