Tutorial Exercise 2.3: Vertical Fine-Tuning
The previous exercise of this chapter deals with vertical fine tuning, used to move a selected node to a different level. From the section 1 of the tutorial you already know that uDraw(Graph) generates a hierarchical layout where all edges are pointing downwards. By moving one node to a new level, the hierarchical property of the drawing might be violated. So for example, when you move a node one level downwards, then probably the children of this node need to be moved as well (and their children, and so on) to guarantee that each child node is at least one level under its parent node.
Ok, enough explanation. Just do it: Select a node, for example one at the topmost level, hold down the left mouse button and move the mouse slowly downwards. As soon as the mouse pointer reaches the center coordinate of the next level, a dynamic incremental layout process starts to move the node to the new level and to rearrange the subgraph with the children (as it is explained above). Incremental layout may take some time, especially when large parts of the graph have to be rearranged. So either you have to be patient or you have to order a more powerful computer. ;-)
It is possible that the total graph layout is getting worse after several vertical fine tuning steps. So start the global layout algorithm to clean up that mess. You can see that uDraw(Graph) keeps the nodes at their current level to preserve your vertical fine tuning operations. You can also play with the other automatic layout operations in the Layout menu. Layout/Improve Edges keeps the order of nodes by re-routing the edges and Layout/Improve Spacing keeps the order of nodes and the edge routing while modifying the space between them. If you want the nodes back at their initial level after starting the layout algorithm, then you must deactivate the "Keep Nodes at Levels" check button (so it is no longer highlighted) in the layout algorithm dialog, available after selecting menu Options/Layout Algorithm. Do not forget to press the ok button in the dialog to activate this new setting!
End of Exercise 2.3. Go back to the Section 2 Overview.
