Most of the "Edit" menu's entries are self-explaining. Therefore, only some important commands are explained.
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Select two nodes A and B. A is the reference. The command stretches node B until it touches node A.
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Freeze
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Transformations
Set/reset an object's transformation matrix.
Reset
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Transformations
Restore an object's original transformations.
Copy Selected Node Name
Copies the name of the selected node to the clipboard.
Rename Selected Node...
Opens a new dialogue where the new name can be entered.
Group Selected
All selected nodes will be added to a newly created group.
Clone selected
Create an identical copy from the selected node. If a node cannot be cloned you will get a warning message.
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Clone Selected Special... >
Select the nodes you want to clone and click on this option – a new dialogue will be opened:
Recreate links
All connections to other nodes in the "Relationship Editor" will be recreated from the original node(s).
Duplicate with children
If the original node has any parented nodes they will be cloned as well.
Name prefix
If you want to add a prefix to the cloned node(s) enter it here. The name will then be prefix_original_name+number.
Name suffix
If you want to add a suffix to the cloned node(s) enter it here. The name will then be original_name_suffix+number.
Keep current node selection
When enabled the original node selection will be kept, otherwise the new nodes will be selected.
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Back culled selected
Exclude invisible polygons from your selection.