effects use tree structures for organizing the menu structure.
This requires that their parameters are ordered in a tree structured
way. A tree structure may be difficult to specify, but with
the VAC Configuration Dialog tree field this is an easy task.
The tree field.
A tree field consists of a tree where all the tree items
are displayed. On the right hand side of the field, there
are the parameter fields and values for each item. The parameters
of a tree applet may be very different, they can, for example,
include selection fields, file fields, color
buttons, text fields and check
boxes. By clicking on one item in the tree, you can access
the parameter values for that specific item. The values of
the parameter fields will be updated in the tree structure
when selecting another item. By clicking on the add child
button, you add a subitem to an existing item. Clicking on
the add sibling button, will add a new item to the end of
the column. The delete button will delete the selected item
and all the subitems.