Filter Elements
Input Data
Select the Source of the data that will be used as input to the function:
| Selection | Design elements you have interactively selected in the Design Window. |
| Visible | Design elements that are visible in the loaded layer. Elements that have been specifically hidden are excluded. This a quick way of selecting all visible elements in a layer without having to explicitly select them. |
| Layer | One or more layers that you select. Names of layers currently loaded in the Design Window are shown in bold. |
For large datasets, you may prefer to select a layer rather than load that layer and select all of the elements in the layer. Selecting a non-applicable layer will have no effect. In most cases, an error icon 
will indicate the chosen input layer is not valid. Hover over the icon to view a validation hint.
Settings
Filter Expression
Click the drop-down or click on the ellipsis button to build a Filter Expression.
The Filter Expression will evaluate and return a Boolean (True/False value). Elements that return a True value will be written to the specified Output layer.
Output Layer
Use the drop-down to select an Output Layer.
Tip: In the Layer Selection pane, you can right-click on the Layers node (or a folder) to Add a new layer.
Replace Existing Contents
If the Output layer already exists, select this check box to overwrite the layer.
If you do not select the check box, filtered elements will be added to any existing elements in the layer.
Apply
Finally, click Apply to intersect triangulation sets.
Check that the result of the operation is what you expect. If necessary, use CTRL+Z to undo.
