The objective of the analysis is to derive variables which may have social or experiential significance. At the building or small urban scale, depthmapX can be used to assess the visual accessibility in a number of ways.
It can produce point isovists, that is, polygons representing the visually accessible area from a location, along with measures of those polygons such as perimeter, area and so on , or it can further join a dense grid of isovists into a visibility graph of intervisible points with graphs of up to about point locations. The visibility graph may then be analysed directly using graph measures, or used as the core of an agent-based analysis.
In the agent-based analysis a number of software agents representing pedestrians are released into the environment. Each software agent is able to access the visual accessibility information for its current location from the visibility graph, and this informs its choice of next destination.
The numbers of agents passing through gates can be counted, and compared to actual numbers of pedestrians passing through gates. At the small to medium urban scale, depthmapX can be used to derive an 'axial map' of a layout. That is, derive a reduced straight-line network of the open space in an environment. The axial map has been the staple of space syntax research for many years, but the mathematical derivation of it is novel. The automatic derivation allows an objective map for research into formal and functional attributes of cities and buildings.
Once the map has been generated, it may be analysed using graph measures, and the measures may be transferred to gate layers in order to compare with indicators of pedestrian or social behaviour. For larger systems where the derivation algorithm becomes cumbersome, pre-drawn axial maps may be imported. Axial maps may be broken into segment maps, or segment maps, such as road-centre line maps, may be imported directly.
These maps can be analysed using a variety of techniques. The rules used for the analysis can be based on segment steps, angular turns from one road interjunction to another, or can be determined by the physical distance along the roads.
For example, the number of shortest angular paths through a segment may be calculated, or the average road distance from each segment to all others may be calculated. Many features are covered in this tutorial by Joao Pinelo. You may also find tutorials for 7. These tutorials are in PDF format. Note that they were originally prepared for version 7.
We hope that you will find no problems using them to learn version 8. Original drawings by J Hanson, digitised by A Turner. In addition gallery. This page stores all versions of the Depthmap Researchers' Handbook. At the building or small urban scale, depthmapX can be used to assess the visual accessibility of a place in a number of ways.
It can produce point isovists, polygons that represent the visually accessible area from a location and isovist paths that show how the view changes when moving through a space. Isovists are the core element behind Visibility Graph Analysis VGA , acting as the joining mechanism that converts a dense grid to a graph of intervisible points a visibility graph , which may then be analysed using various graph measures.
VGA can also be used as the core of an agent-based analysis. In this type of analysis, a number of software agents representing pedestrians are released into the environment. Each software agent is able to access the visual accessibility information for its current location from the visibility graph, which informs its choice of next destination. The paths of the agents and their numbers passing through gates can be counted, and compared to actual behaviour of pedestrians passing through gates.
At the small to medium urban scale, depthmapX can be used to derive an axial map of a layout. This means it can derive a reduced straight-line network of the open space in an environment. The axial map has been the key analysis method of space syntax research for many years, but the mathematical derivation of it is novel.
The automatic derivation within depthmapX allows an objective map for researching spatial form and function. Once the map has been generated, it may be analysed using graph measures, and the measures may be transferred to gate layers in order to compare with indicators of pedestrian or social behaviour.
For larger systems where the derivation algorithm becomes cumbersome, pre-drawn axial maps or downloaded maps such as road-centre lines may be imported. Axial maps can also be converted to segment maps by breaking down long axial lines into a sequence of segments that lead from junction to junction.
These may be analysed using a variety of techniques that accumulate depth, such as the degree of angle change from one segment to another, metric distance, or segment steps.
0コメント