To analyze metric reach, directional reach, intersection reach, and more.
There is another version of this software which can be run in Rhino 5 (32-bit) as a series of Grasshopper definitions. The toolkit can be downloaded from https://www.food4rhino.com/resource/grasshopper-reach-analysis-toolkit
The theoretical foundation of the reach analysis can be found in Peponis, J., Bafna, S., & Zhang, Z. (2008). The connectivity of streets: reach and directional distance. Environment and Planning B: Planning and Design, 35(5), 881–901.
The algorithms and implementation details can be found in the following two publications:
Feng, C., & Zhang, W. (2019). Algorithms for the parametric analysis of metric, directional, and intersection reach. Environment and Planning B: Urban Analytics and City Science, 46(8): 1422–1438.
Feng, C., & Zhang, W. (2017). Grasshopper reach analysis toolkit: Interactive parametric syntactic analysis. In T. Heitor, M. Serra, J. Silva, M. Bacharel, & L. Silva (Eds.), Proceedings: Eleventh International Space Syntax Symposium. Lisbon: Instituto Superior Técnico, Departamento de Engenharia Civil, Arquitetura e Georrecursos, Portugal.