OCTOR: Subset selection in recursive pattern hierarchies

We present an approach for encoding and specifying selections in recursive pattern hierarchies. Hierarchies of patterns of features or other modeling entities are used in architectural and mechanical CAD to eliminate laborious repetitions from the design process. Yet, often a subset of the repeated occurrences in the model must be edited. Specifying a desired selection is often tedious and difficult. Our approach addresses these two drawbacks simultaneously, offering an effective and intuitive solution which requires only two mouse-clicks to specify any one of a wide range of selections, including selections in recursive hierarchies. The selection has a concise representation that is simple to compute.