ObjectARX ® provides interfaces where you can overrule at runtime, or modify, default behavior of a target class derived from AcDbEntity, AcDbObject, or AcGiDrawable, without the overhead of implementing a custom entity.
The base overrule functionality is provided by AcRxOverrule. Specialized overrule classes are derived for modifying behavior implemented in the following function types:
- Grip point
- Snap
- Subentity
- Transform
- Geometry
- Visibility
- Object properties
- Certain AcDbObject
- Draw
The default behavior of the listed overrule functions is to call the function being overruled, without modification. To modify the default behavior, derive from one of the specialized overrule classes and override the corresponding virtual functions defined by that overrule class.
The overruled behavior is then invoked for a target class at runtime when the following conditions are met:
- The application-wide overrule switch is turned on.
- A corresponding overrule has been registered for the target class.