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Feature References
Feature references are the dependencies between different features in a design. They are created in the context of a single part, or in the context of an assembly.
Feature dependencies can be local references or external references. Local references only reference geometry of the model in which they were created. External dependencies reference geometry outside the model in which they were created.
For external references, the assembly in which the two components existed when the dependency was created is another important characteristic of the dependency. For example, an assembly cut intersecting the assembly components and using their geometry is a local reference in the context of this assembly. However, if an assembly feature of a subassembly component references geometry outside the subassembly, such as a top-level part component, then this type of reference is considered external for the subassembly.
If a feature is set as current, all models that are referenced by this feature or that are referencing this feature appear in the Parent and Children trees. You can expand these models to show the features that participate in dependencies with the current feature. If a component is set as current, all parents and children of its features appear.
Models with only placement dependencies do not expand to features, because their features do not participate in the dependency. Exceptions are feature relations using external parameters and merge references.