3.2.3 Isovist

3.2.3 Isovist

Isovist(g) measure the extent of visibility of a space. An Isovist(g) is defined as the area that can be seen from a single vantage point. Benedikt (1979) suggested several properties that can be derived from an Isovist(j) polygon for the characterization of spatial situations i.e. area, perimeter, compactness, and occlusivity. Using multiple vantage points will most likely generate a different understanding of the environment.

(ESUM Urban Sensing Handbook,2017)

Area: is the unobstructed radial polygon. Higher the area more the space revealed increasing you awareness and possibly understanding of the building.

Perimeter: Length of the edges of all space visible from a location. Observing the minimum and maximum extents of the length of different vantage points help effectively make design decision of space function. For example, if the extent is reduced you are entering a more private, hidden, or enclosed area.

Compactness: Ratio of area to perimeter (related to an ideal circle). It represents the relative dispersal of points from the vantage point. For example region of plan in which an observer’s spatial experience is consistent if the dispersal of point is less.

Occlusivity: Length of occluding edges. Occlusion occurs when vision is not constrained by a simple surface but by the edge of a surface which hides something from the view. For example, higher the level of occlusion in a n isovist perimeter, the greater the sense of mystery. or spatial ambiguity.

Isovist(j) value measures the extent of visibility of a space. An Isovist is defined as the area that can be seen from a single vantage point. Isovist can be evaluated by its area, perimeter, compactness, occlusivity.

Figure 3-5 (a) Isovist Source Link : https://en.wikipedia.org/wiki`/File:Isovist.svg (b) sourcelink:https://link.springer.com/referenceworkentry/10.1007%2F978-3-319-70658-0_5-1

(b) (a)