US Patent 7571079 Aware and active features for computer-aided design systems

Processing data in a computer-aided design (CAD) system includes determining that a feature of a three-dimensional model has a condition that requires correction. The condition is automatically corrected by performing an action. The action may be an action that reorders a sequence of features in the three-dimensional model, an action that changes at least one parameter of the feature, an action that deletes a feature reference, or an action that changes a feature reference. Furthermore, the action may have one or more constraints that bound the action to a set of features that are directly and indirectly related to the feature on which the action operates.