Transformations

Applying transformations to a tree can be accomplished with the operations under the Transformation menu, which allow the user to add movements, insertions and deletions to a tree.

Adding a Movement

A move transformation is applied to a tree by first selecting the node you wish to move and choosing Transformation|Move or the   Move button on the toolbar. This will mark the node as the source of a move and highlight it on the drawing canvas.

After selecting the move source, the user can select a move target node and choose Transformation|MoveTo or the   Move To button on the toolbar to complete the move. Selecting a move target node will result in an arrow being drawn from the source node to the target node signifying the move.

Move sources and targets can be either internal or terminal nodes.

If the move source node has daughters or if daughters are added to the move source node, a box will be added around the sub-tree headed by the move source node. A box will also be drawn around the move target node if it has daughters or if daughters are added to it.

If either the move source or move target is deleted or cut (or if a dominating node is deleted or cut) the move arrow will be removed.

Tree Builder provides no direct support for actually moving the source node to the target node leaving behind a trace identifier (t). If you wish to do so, you will have to make changes to the structure of the tree. In such a case, however, the check tree operation may signal the change as an error.

Canceling a Movement

A move can be cancelled by selecting the source of the move and choosing Transformation|Cancel Movement which will remove the move arrow.

Editing a Movement Arrow

The movement arrow is initially drawn in a default location and shape, which may cross other nodes or for other reasons be unsuitable. You can change the shape of the arrow by selecting the source of the move and choosing Transformation|Edit Arrow or the   Edit Arrow button on the toolbar. This will draws a control point on the drawing canvas, which can be dragged by the mouse to change the shape of the movement arrow for the selected node.

The new location and shape will be saved by the program.

Adding an Insertion

Tree Builder provides support for do and it insertions. To add an insertion to a node, select the node and choose Transformation|Add Insertion or the   Add Insertion button on the toolbar. This will open a dialog prompting the user to enter an insertion for the selected node. The insertion will be added below the selected node and point to it with a double lined arrow.

Removing an Insertion

An insertion can be removed by selecting the insertion and choosing Edit|Delete.

Adding a Deletion

Tree Builder provides support for deletions. To add a deletion to a node, select the node and choose Transformation|Add Deletion. This will result in a double lined arrow being drawn from the selected node and terminating with a null symbol. The null symbol can be changed by the user by selecting the deletion and choosing Structure|Rename.

Removing a Deletion

An deletion can be removed by selecting the deletion and choosing Edit|Delete.