Fundamentals > Fundamentals > User Interface Basics > Chains and Surface Sets > Chains > To Modify Chain Types and References
To Modify Chain Types and References
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This topic discusses chain modification while working inside of a tool and using the Chain dialog box. If you want to modify a chain while working outside of a tool, you can use the SHIFT key to clear the selection of individual items from the ends of a chain or use the CTRL key to remove an entire chain from the selection set. Refer to About Selection under See Also for more information about clearing a selection.
1. Construct a chain and open the tool in which to work with the chain, or select a feature that contains an existing chain that you want to modify, right-click, and select Edit Definition from the shortcut menu.
2. Locate the Detail collector that contains the chain that you want to modify. Detail collectors are located on the panel. Note that you cannot use the Summary collector (located on the dialog bar) to modify a chain.
3. Click Details. Creo Parametric pauses the tool, opens the Chain dialog box, and displays the attributes for the chain.
4. If the panel Detail collector contains more than one chain, select the chain to modify from the chain list in the Chain dialog box. The chain attributes are displayed.
5. Click the References tab to modify the chain type and references.
6. Click Standard to change the selected chain to a One-by-One chain or modify this chain type. The References tab contains the following option.
References collector—Contains the references for the selected chain. References consist of one or more adjacent edges or curves, or a single-piece Intent chain. To modify a reference, click the reference to activate the collector and then select a new reference from the model, select additional references, or remove the reference. Notice that you can also use the References shortcut menu command from inside the graphics window to activate this collector.
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All references in the collector are ordered according to the internal direction of the chain with the start point at the top.
You can remove references only at the top and bottom of the list. Additionally, if the collector contains only one reference, this reference cannot be removed. However, you can select another reference to replace it.
7. Click Rule-based to change the selected chain to a Tangent, Partial Loop (From-To), or Complete Loop chain, or to modify these chain types. The References tab now contains the following:
Anchor collector—Contains the anchor reference for the selected chain. Anchor references consist of an edge or a curve. To modify the anchor, click the reference to activate the collector and select a new anchor reference from the model. Notice that you can also use the Anchor shortcut menu command from inside the graphics window to activate this collector.
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You can only replace the anchor reference, you cannot remove it.
Rule—Displays the following chain types enabling you to modify them:
Tangent—Constructs a tangent chain by using all edges that are tangent to their neighboring edges and tangent to the anchor, if possible. Note that if an anchor reference is used it must be an edge.
Partial loop—Constructs a Partial Loop (From-To) chain by using all loop reference items (curves or edges that partially bind the quilt or solid surface to which it belongs) located between the anchor (start-point) and the extent (end-point) references. The Extent Reference collector and the Flip button appear. Note that you must select an anchor to use the Partial loop option.
Complete loop—Constructs a Complete Loop chain by using an entire loop of reference items (curves or edges that completely bind the curve, quilt, or solid surface to which it belongs). The Loop Reference collector appears. Note that you must select an anchor to use the Complete loop option.
Extent Reference collector—Contains the extent (end-point) reference for a Partial Loop chain. Extent references consist of an edge or a curve that can belong to a valid loop reference (solid surface, quilt, or curve). To modify the chain, click the reference to activate the collector and then select a different extent reference from the model. Notice that you can also use the Extent Reference shortcut menu command from inside the graphics window to activate this collector.
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You must select the Partial loop chain type to use this collector.
Range—Displays the Flip button. The Flip button changes a portion of the loop reference in a Partial Loop (From-To) chain. Note that you must select the Partial loop chain type, and more than one Partial Loop chain must be formed by the selected anchor, extent, or loop reference in order to use this button.
Loop Reference collector—Contains the loop reference for the Complete Loop chain. Consists of a quilt or a solid surface loop reference. To define a new loop range, click the reference to activate the collector and then select a new loop reference from the model. Notice that you can also use the Loop Reference shortcut menu command from inside the graphics window to activate this collector.
8. Click OK. Creo Parametric saves the changes, closes the Chain dialog box, and resumes the tool.
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You can construct a chain by clicking Add in the Chain dialog box and selecting chain references from the model.
To remove a chain from the Chain list, select the chain and click Remove in the Chain dialog box.
Remember that you can hold down the CTRL key and select a reference to either add an additional reference or to clear a selected reference.
To clear references in the active collector, click Remove or Remove All on the shortcut menu that appears when you right-click in the collector. Alternatively, click Clear on the shortcut menu that appears when you right-click in the graphics window.
To easily locate references in the Chain dialog box, place your pointer over the reference in a collector. Creo Parametric dynamically highlights the reference on the model.
Notice that as you modify a chain in the Chain dialog box, Creo Parametric dynamically displays the changes in the graphics window.
When the Chain dialog box is open, you can perform Undo or Redo operations if the tool or feature supports Undo or Redo operations.