Compose

Select the geometry objects that you want to compose in the Graphics window. The objects appear in the list. If the geometry sequence includes user-defined selections above the node, choose to select objects, or choose one of the selection nodes from the list next to .

Click the button to toggle between turning ON and OFF the selections.

Select the check box to use the selected solid geometry objects for further geometry operations.

In the field, enter a set formula involving the names of the selected geometry objects — for example, r1+c1*(c2-r2) — to take the union of r1 and the object that is the result of the intersection between c1 and the set difference where r2 is subtracted from c2. Use the binary operations +, *, and - for set union, set intersection, and set difference, respectively. The precedence of the operators + and - are the same. The operator * has higher precedence. You can override the precedence rules using parentheses. When you change the set formula, the selection is automatically updated.

To create a geometry object without interior boundaries, clear the check box. This can be useful to simplify a geometry where the interior boundaries do not separate domains with different physics nodes or materials, for example.

You can change the settings for the list if you experience problems with the compose operation. Geometric entities that have a distance less than the repair tolerance are merged.

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The default value in the list is , which for 3D objects represented using the CAD kernel determines the repair tolerance internally. For 3D objects represented using the COMSOL kernel, and for 2D and 1D objects, means a relative repair tolerance of 10−6.

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Choose to enter a value for the field (the default is determined by the main node’s setting). This value is relative to the largest absolute value of the coordinates of all input objects.

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Choose to enter a value for the field (the default is determined by the main node’s setting; SI unit: m). This value uses the same unit as the geometry sequence’s length unit.

When you build this feature, the relative and absolute repair tolerances are set to the values that are used (with a precision of two digits), which can be useful when you have set to .

If you want to make the resulting entities contribute to a cumulative selection, select a cumulative selection from the list (the default, , gives no contribution), or click the button to create a new cumulative selection (see Cumulative Selections).

Select the check box to create predefined selections (for all levels — objects, domains, boundaries, edges, and points — that are applicable) in subsequent nodes in the geometry sequence. To also make all or one of the types of resulting entities (domains, boundaries, edges, and points) that the resulting objects consist of available as selections in all applicable selection lists (in physics and materials settings, for example), choose an option from the ( if in a geometry part; in a plane geometry under a work plane in a 3D component) list: , , , , or . The default is , which is suitable for use with materials and physics defined in domains. For use with a boundary condition, for example, choose . These selections do not appear as separate selection nodes in the model tree. Select to not make any selection available outside of the geometry sequence.