Abstract: A multi-user CAx editing system may comprise a plurality of editing clients. The editing clients may be configured to maintain data consistency for geometric elements created within each local instance of a model of an engineering object. For example, each of the plurality of editing clients may include a synchronization module configured to identify one or more distinguishing parameters for each locally created geometric element and generate a unique persistent label for the geometric element, and communicate the unique persistent label and the distinguishing parameters to other editing clients. The communication may occur via a collaborative editing server. The other editing clients may find a geometric element within their local instance of the model that matches the distinguishing parameters and associate the unique persistent label with that geometric element. Subsequent references to the geometric element may be made by referring to the unique persistent label.

Abstract: A computer-implemented method for preventing reference invalidation when reversing operations in synchronous collaborative applications may include (i) storing, on a client, a shared model of an engineering object including one or more features, (ii) receiving, from a user, an operation to be performed on the feature, (iii) before performing the operation, storing, in a command stack on the client, information sufficient to restore the feature to a state prior to performing the operation, (iv) receiving, from the user, a request to reverse the operation, (v) determining whether reversing the operation will create an invalid reference due to a conflicting operation having been performed on the feature at a second client, and (vi) in response to determining whether reversing the operation will create an invalid reference, reversing the operation or performing a resolution operation to prevent the reference invalidation. A system corresponding to the above method is also disclosed.

Abstract: A computer-implemented method for preventing reference invalidation when reversing operations in synchronous collaborative applications may include (i) storing, on a client, a shared model of an engineering object including one or more features, (ii) receiving, from a user, an operation to be performed on the feature, (iii) before performing the operation, storing, in a command stack on the client, information sufficient to restore the feature to a state prior to performing the operation, (iv) receiving, from the user, a request to reverse the operation, (v) determining whether reversing the operation will create an invalid reference due to a conflicting operation having been performed on the feature at a second client, and (vi) in response to determining whether reversing the operation will create an invalid reference, reversing the operation or performing a resolution operation to prevent the reference invalidation. A system corresponding to the above method is also disclosed.

Abstract: A multi-user CAx editing system may comprise a plurality of editing clients. The editing clients may be configured to maintain data consistency for geometric elements created within each local instance of a model of an engineering object. For example, each of the plurality of editing clients may include a synchronization module configured to identify one or more distinguishing parameters for each locally created geometric element and generate a unique persistent label for the geometric element, and communicate the unique persistent label and the distinguishing parameters to other editing clients. The communication may occur via a collaborative editing server. The other editing clients may find a geometric element within their local instance of the model that matches the distinguishing parameters and associate the unique persistent label with that geometric element. Subsequent references to the geometric element may be made by referring to the unique persistent label.