Convert to Surface
Use the Convert to Surface () node to unite and convert geometry objects to a single surface object in a 3D geometry. You can, for example, convert a solid geometry to a surface object for modeling some type of shell. If the input objects include edges or curves, then any parts of those edges or curves that are outside of the resulting surfaces are removed. If the conversion to a surface results in an empty surface, a Warning subnode appears.
It is not possible to create a 3D surface from a set of connected curves or edges, even if they all lie in a plane and could form a planar surface. In such cases, you can instead create a work plane where you add the connected curves and then create a surface from those curves. If your license includes the CAD Import Module, you can also use a Cap Faces feature to create a surface from a set of connected curves.
Enter the properties of the convert operation using the following sections:
Input
Select the geometry objects that you want to convert in the Graphics window. The objects appear in the Input objects list.
Click the Active button to toggle between turning ON and OFF the Input objects selections.
Select the Keep input objects check box to use the selected geometry objects for further geometry operations.
Select the Unite objects check box (selected by default) to unite the input objects before converting them. Clear the check box to convert each object independently. You can change the settings for the Repair tolerance to control the union. Geometric entities that have a distance less than the repair tolerance are merged.
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The default value in the Repair tolerance list is Automatic, 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, Automatic means a relative repair tolerance of 10−6.
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Choose Relative to enter a value for the Relative repair tolerance field (the default is determined by the main Geometry node’s setting). This value is relative to the largest absolute value of the coordinates of all input objects.
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Choose Absolute to enter a value for the Absolute repair tolerance field (the default is determined by the main Geometry 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 first building with Automatic and then switch to manually modifying the tolerance.
Selections of Resulting Entities
Select the Resulting objects selection 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 Show in physics (Show in instances if in a geometry part) list: All levels, Boundary selection, Edge selection, or Point selection. The default is Boundary selection. These selections do not appear as separate selection nodes in the model tree. Select Off to not make any selection available outside of the geometry sequence. From the Color list, choose a color for highlighting the resulting objects selection. See Selection Colors.
Cumulative Selection
If you want to make the resulting entities contribute to a cumulative selection, select a cumulative selection from the Contribute to list (the default, None, gives no contribution), or click the New button to create a new cumulative selection (see Cumulative Selections).
Selections on Input Objects
If you have Named Selections that include entities on the input objects, select the Propagate selections to resulting objects (selected by default) check box to update the selections to corresponding entities on the output objects, when possible. Clear the check box to not propagate the selection to the resulting objects. This can be useful in combination with selecting the Keep input objects check box so that the selections refer only to the input objects.
Assigned Attributes
From the Construction geometry list choose On to make the resulting objects available only in the feature’s geometry sequence. The default option Inherit means that the resulting objects become construction geometry if all input objects are construction geometry. Choose Off to never output construction geometry objects. For more information, see Construction Geometry.
Location in User Interface
To unite and convert geometry objects to a single surface object, in the Geometry toolbar, Conversions menu, click Convert to Surface (). You can also right-click the Geometry node to add this node from the context menu.