Directed Visibility, Overt & Covert Control and Counterpoint are calculated by continually deriving point isovists at stochastically selected locations within the subject area (Psarra & McElhinney, 2014). Geometric information is extracted from each isovist and recorded to all points within its perimeter. As the stochastic sampling repeats, information within regions of common isovist overlap is concatenated, rapidly creating an increasingly accurate and stable field.