About the Geometry and Topology Structure Tree

The Geometry and Topology Structure (GTS) Tree displays the geometry structure of the imported feature. The GTS Tree is located in the main Creo Parametric window in same location as the Model Tree and is displayed by default in the IDD environment. You can manually switch the tree display to the standard Model Tree and Layer Tree using the standard icons in the tree panel, although the other trees are of limited use in IDD.

The GTS Tree consists of a hierarchy of nodes similar to the Model Tree. Each GTS Tree node has an icon that identifies its object type. For example, surfaces are identified by

while datum points are identified by

. You can use standard tools including cut, copy, paste, drag and drop, and additional IDD-specific tools to manipulate the structure and organization of the GTS tree. Manipulation of the structure is often helpful to facilitate repair or modification of the import geometry for large or complex import features.

• Root Node—This is the topmost node of the tree and represents the import feature being redefined. It has no parent node or sibling nodes on the tree. It must have at least one sub node.

• Base Node—The immediate sub nodes of the root node are called base nodes. Any node type can be a base node except a datum node.

• Complex Node—Nodes that have sub nodes are called complex nodes. A complex node may itself be a sub node. You can expand or collapse the complex node to show or hide its sub nodes on the GTS Tree. Complex nodes can be of the following types:

◦ Component Node—A collection of related surfaces in an imported model is called a component node. Surfaces within a component node are considered to be logically joined even if they have gaps between them. You can use the Repair mode to repair the gaps between the surfaces. Surfaces that belong to different component nodes are explicitly separated, unless the components to which they belong are adjacent and you join them to create a combine node or they are merged with each other.

◦ Combine Node—A combination of nodes, including surfaces, datum, or other complex nodes is called a combine node. For certain operations that you perform, combine nodes are created automatically. You can also create a combine node manually.

A merge node cannot be included in a combine node.

◦ Datums Bin Node—A special base node that contains all the datum entities read in by the import feature, or one that you create without an explicitly active node. You can move a datum from this base node and place it under other complex nodes on the GTS tree. Similarly, you can move a datum from complex nodes and place it under base nodes on the GTS tree.

◦ Exclude Bin Node—Duplicate surfaces in the imported feature are often automatically excluded. These surfaces are placed in the Exclude Bin located at the bottom of the GTS tree when you enter IDD. They are not considered for any IDD manipulations and are hidden in the graphics window when in the IDD environment. You can also manually exclude additional surfaces or include surfaces that you no longer want excluded.

◦ Merge Node—When you perform a merge operation on any two quilts defined by any two nodes, such as surface leaf nodes, procedure nodes, or other complex nodes, a merge node is created. You can perform a merge operation only between two nodes if they both represent valid or continuous quilts. Merge nodes can only be base nodes or sub nodes of other merge nodes but cannot be part of a combine node.

• Leaf Node—Nodes that do not have sub nodes are called leaf nodes. A leaf node has a parent node, but does not have any child nodes and is therefore not expandable. The types of leaf nodes are:

◦ Surface Node—An individual surface in an imported model is called a surface node. Surface nodes can be analytical such as conical, spherical, planar, cylindrical, and so on, or non-analytical such as splines, b-splines, or beziers.

◦ Datum Node—Datum objects such as a datum point, datum plane, datum coordinate system, datum axis, or datum curves in an imported model are called datum nodes.

◦ Procedure Node—A procedure node is the result of converting one or more surfaces into a procedure surface, such as a revolved or extruded surface. A procedure node may comprise of many individual surfaces. You cannot expand a procedure node and it is always treated as a single entity by IDD tools and operations.

Creo Parametric analyzes the imported model and displays the GTS Tree based on the geometry and topology structure of the feature. By default, you may see one or more component or surface leaf nodes, or both, on the GTS tree representing individual quilts of the import feature. A Datums Bin node may also be present if the import feature contains datum entities. You may see an Exclude node containing duplicate surfaces if duplicate surfaces were automatically excluded during the creation of the import feature.