Adding Visibility to Visibility Graphs: Weighting Visibility Analysis with Attenuation Coefficients
This work addresses a gap in design computation and space-syntax research by incorporating weather effects into visibility analysis, which is incremental as it builds on existing visibility graph techniques.
The paper tackles the problem of ignoring weather conditions in visibility analysis for urban environments by introducing a method to weight visibility graphs with attenuation coefficients for rain, fog, and snow, demonstrating variance between straight line-of-sight and reduced visibility in sample environments.
Evaluating the built environment based on visibility has been long used as a tool for human-centric design. The origins of isovists and visibility graphs are within interior spaces, while more recently, these evaluation techniques have been applied in the urban context. One of the key differentiators of an outside environment is the weather, which has largely been ignored in the design computation and space-syntax research areas. While a visibility graph is a straightforward metric for determining connectivity between regions of space through a line of sight calculation, this approach largely ignores the actual visibility of one point to another. This paper introduces a new method for weighting a visibility graph based on weather conditions (i.e. rain, fog, snow). These new factors are integrated into visibility graphs and applied to sample environments to demonstrate the variance between assuming a straight line of sight and reduced visibility.