Isovist
They can be analysed to compute the intervisibility of positions in a whole environment (Turner et al., 2001) and have become useful in industry when creating floor plans for certain spaces or determining experience of architecture (Franz and Wiener, 2005).
Benedikt (1979) originally proposed isovists to be an objectively basic element which captures spatial properties by describing the visible area from a single observation point (Franz and Wiener, 2005).
Environmental psychologist James Gibson (1966) was a pioneer in the concept of examining the relationship between a viewer and their environment when developing his first model of the geometry of visual perception (Dawes and Ostwald, 2018).
Gibson proposed three key characteristics which influence this relationship; the first being “ambient” to describe how any individual's understanding of an environment is restricted, the second being “optic” as the realisation environmental information is a constituent of vision, and the third being “array” as the ordered arrangement of elements as part of a larger system (Dawes and Ostwald, 2018).
Gibson identified a ray of light as a geometrically structures source of information (Dawes and Ostwald, 2018) and as such, assisted in forming the foundations of visual perception concepts.
Benedikt was influenced greatly by the ideas that were proposed by Gibson, allowing him to push theoretical boundaries to pave the way for future research (Emo, 2018).
Further research has also determined that the largest and smallest Isovist areas in a given space have been found to be directly correlated to an individual's perception of the most exposed and most visible sections of a building.
In this building, the isovist is constructed cyclically allowing the visitor to remain more actively engaged in each individual piece of art, creating spatial variety (Benedikt, 1979).
In the context of urban areas and built environments, isovists are useful in analysing street life, safety and economical attractiveness (Van Nes, 2011).
They cover some subsets of sources of visual information for the individual which can be used to investigate or even predict human behavioural and cognitive responses to buildings (Dawes and Ostwald, 2013).
When these two elements are combined, this theory allows a deeper understanding of environments and has been slowly accepted into environmental preference research (Dawes and Ostwald, 2013).
Prospect and refuge can be measured individually or in combination to examine their relative sensitivities or robustness and later be applied to more complex architectures (Dawes and Ostwald, 2013).
It was found the intending criminal is concerned with one's spatial characteristics, in particular the inconspicuousness of the target and their concealment from detection, attributes which are both impacted by the isovist.
The isovist has therefore been found utilitarian to optimise space for a range of purposes (Desyllas, 2000; Hillier and Shu, 2000) when considering crime, spatial occupation, and rental returns.
