Balloon layout mode is similar to radial layout mode
with the following differences:
- Radial layout mode arranges all nodes in circles around the root node; balloon layout mode arranges child nodes in circles around the parent node.
- In radial layout mode, there is only one circle center for the entire tree; in balloon layout mode, each subtree has a different circle center.
In balloon layout mode, each subtree forms a balloon.
The following figure shows examples of balloon layout mode.

Examples of balloon layout mode
To set balloon layout mode:
Use the method setLayoutMode:
treeLayout.setLayoutMode(ibm_ilog.graphlayout.tree.TreeLayout.BALLOON);