#### 2.1.7.6. CAD Selection Rule

The CAD Selection Rule allows you to define the extent of a modeling ply or OSS based on a CAD surface or solid geometry. Elements are selected if they lie within the enclosure of a defined volume. The volume is set by the size of the CAD solid geometry or the CAD surface geometry in combination with specified Capture Tolerances. This means that a flat CAD surface geometry can be used to define a ply on a curved mesh surface. Figure : Example CAD Selection Rule shows a selection inside a curved mesh enclosed by a flat surface with relatively high negative and positive capture tolerances.

Figure : Example CAD Selection Rule

CAD Selection Rules have the following settings:

Figure : CAD Selection Rule Properties

- Geometry: Virtual Geometry defining the basic selection.

- Include Rule Type

Capture tolerances are only used for non-solid geometries (surfaces).

- Use Defaults: Defines if the default value is used. The default value is the Offset property of the CAD geometry.

- In-plane: Increase the in-plane extension by this value.

- Negative: Capture tolerance reverse the surface normal.

- Positive: Capture tolerance along the surface normal.

Negative values are also supported.

Figure : Capture Tolerances

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