The first sort mode sorts the bigger branches to the top, the third sorts them to the bottom.
The second sort mode sorts the bigger branches to the edges of the tree and the smaller branches to the center.
The fourth and fifth mode are designed to sort the tree for the radial tree display mode.
The fourth mode does the opposite of the second mode: it sorts bigger branches to the center and smaller ones to the borders of the tree.
The fifth mode alternates between second and fourth mode.