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System.IUnknown | +---System.IDispatch | +---System.CATBaseUnknown | +---CATIShapeFeatureProperties
Usage: you can reimplement this interface by deriving the supplied CATMmrShapeFeaturePropertiesAdapter adapter class.
interface CATIShapeFeatureProperties
Interface to retrieve characteristics of a solid feature.
Role: A solid feature is a geometrical feature which references 3D geometry.
There are two kinds of solid feature: the form and the contextual feature.
Form versus Contextual Feature
A Pad, a Pocket, a Groove, are different features: some add matter, while some remove it. However, they share a common point: they have a form and are therefore called form features. What is that?
Take a Groove for instance. From its input parameters, a Curve and a closed Sketch, one can easily derive a shape (a Form) by sliding the Sketch along the Curve. The resulting solid has then to be operated with the Part's shape as it exists prior to the definition of the Groove, by removing matter (thanks to a boolean remove operation in that case).
The fact that those features can be applied by first computing their form and then operating the form with the current shape of the set defines the form feature. The form of such a feature is sometimes called its footprint.
In contrast to form features, contextual features cannot be applied by computing a standalone footprint first, and operating it with the current set in a second step. Fillets, Drafts, and generally all Dress up Features fall into this category, because their shape is determined not only by their own input parameters, but also by the local topology of the target body (hence their name). Contextual features do not have a footprint.This interface enables you to retrieve (or to define) the type of the solid feature thanks to the two first methods (IsAContextualFeature and IsAFreeFormFeature ) which are of course exclusives (except for the Body feature, see below the section dedicated to this feature, and the features representing the boolean operations)
Polarity of the Solid FeatureIt must be noticed that the fact that some features add and some others remove matter from the Part is not linked to the Form/Contextual classification. A Draft is a Contextual Feature that adds matter, while a Chamfer, still contextual, removes it. A Shaft and a Pocket are Form Features that create and remove matter respectively. The GetPolarity method enables you to retrieve (or to define) the intrinsic polarity of a solid feature.
Body Feature ImplementationThis interface is implemented on the Body feature. In this case, only the GetPolarity method is valid.
BOA information: this interface CAN be implemented using the BOA (Basic Object Adapter). To know more about the BOA, refer to the CAA Encyclopedia home page. Click Middleware at the bottom left, then click the Object Modeler tab page. Several articles deal with the BOA.
public virtual int CanBePatterned( | )const = 0 |
public virtual CATUnicodeString GetPolarity( | )const =0 |
public virtual CATLISTV(CATISpecObject_var) GiveMeYourBRepSpecifications( | )const = 0 |
public virtual CATLISTV(CATISpecObject_var) GiveMeYourFavoriteSketches( | )const = 0 |
public virtual int IsAContextualFeature( | )const =0 |
public virtual int IsAFreeFormFeature( | )const =0 |
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