Method for cell selection during feature generation in a computer-implemented solid modeling system

1. Field of the Invention A computer-implemented solid modeling system that generates Rib and Web features. One or more attribute values are set to indicate whether extended start and end segments for each chain of an open profile modeled in the system intersect with a part modeled in the system. The open profile and a sheet with attributes and their specified behaviors are inserted into the tool. The tool, which is generated from the open profile is united with the part to create a cellular topology graph structure, wherein the attributes get propagated to one or more cells of the cellular topology graph structure. The Rib or Web feature is then generated from one or more cells selected from the cellular topology graph structure based on the propagated attribute values.