About the Geometry and Topology Structure Tree
The Geometry and Topology Structure (GTS) Tree displays the geometry structures of the imported features. The GTS Tree in Import DataDoctor (IDD) is located in the same location as the Model Tree in the Creo Parametric window and is displayed by default in the IDD environment. You can switch the tree display to the Model Tree or the Layer Tree using the standard icons in the tree panel though the Model Tree and the Layer Tree are of limited use in IDD.
The GTS Tree consists of a hierarchy of nodes. Each GTS Tree node has an icon that identifies its object type. 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.
The GTS tree includes the following types of nodes:
• 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 base node.
• Base Node—The immediate sub-nodes of the root node are called base nodes, for example, the body nodes that represent the solid bodies of an imported feature and the quilt nodes that contain the quilts of the imported feature. These top-level GTS Tree nodes represent the body structure of the imported features.
• Sub-node— Any node under a base node is called sub-node. For example, the individual component nodes or surface nodes that are contained within the body and quilt nodes are sub-nodes.
Nodes are further classified as follows:
• 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:
◦ Compound Node—A top-level node that consists of component sub-nodes is a compound node. Each component node is a collection of related surfaces. Surfaces within a component node are considered to be logically joined even if they have gaps between them. You can 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—For certain operations that you perform, combine nodes are created automatically. You can also create a combine node manually.
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A merge node cannot be included in a combine node.
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◦ Exclude Node—Duplicate surfaces in the imported feature are often automatically excluded. These surfaces are placed in the Exclude located at the bottom of the GTS tree when you enter IDD. They are not considered for 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:
◦ Quilt Node—An individual surface in an imported model is called a quilt node. Quilt 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.
◦ Facet Node—A single facet body in an imported model is represented by a facet node.
◦ Analytical Surface Conversion Node—An analytical surface conversion node is the result of converting one or more surfaces into a procedure surface, such as a revolved or extruded surface. An analytical surface conversion node may comprise of many individual surfaces. You cannot expand this node and it is always treated as a single entity by IDD tools and operations.
Creo Parametric analyzes the imported models and displays the various nodes on the GTS Tree based on the geometry and topology structure of the imported features. By default, you may see one or more compound or quilt nodes, or both, on the GTS tree representing individual quilts of the import feature. A Datum 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.