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When viewing a person or a firm, click on the "network" button to see a completely new feature of PCAD: an interactive graphical display of relations between people and the firms they were associated with.


The visualization is in the form of a simple network graph.

  • Click on a node to view a menu with basic details and a link to the person's or firm's details page.
  • You may expand the graph in any direction by selecting "show related" from the pop-up menu.
  • When a node (person or firm) is un-expanded, the node graphic is displayed as a hollow circle or square; when all existing relations of a node are displayed, the graphic is filled in.
  • The root node is marked by an extra outline in red. You may re-set the root node by clicking on a node and selecting "re-center" from the menu.

A few additional tips:

  • You may zoom and pan the graphic with the mouse wheel and drag.
  • While the layout is determined by an algorithm, you can adjust it to some degree by dragging nodes. This can be useful to "untangle" complex graphs.
  • When a graph becomes very complex the "recenter" feature can be useful to start over from a new root node.


A few examples will illustrate some of the ways the network visualization might be useful.

The Southeast Housing Architects group (details) was formed in 1940 for a specific project and brought together a number of important architects (network) working in Los Angeles at the time.

A similar case in Seattle was the Artists and Architects Group (details), a collaboration between a group of noted Northwest modernists (network).

Also in post-WWII Seattle, the firm of John Graham, Architects and Engineers (details) was connected with a large number of well-known architects of the day (network).


The core rendering and display interactions of the network visualization were implemented via the powerful d3 visualization library. An equally important component is the WebCola library, which provides a far more sophisticated layout algorithm than d3, and can be integrated with d3 to serve as a layout engine for directed graph visualizations. WebCola also manages quite elegantly the task of re-drawing and re-adjusting layout. This was a crucial requirement to support interactivity, when expanding the graph may result in a dramatically different set of nodes and connections.

Future Directions

In the future we hope to enhance this feature in several ways. One direction will be to incorporate a temporal dimension, to add the ability to explore relations within specific time frames. This would allow more precise visualizations in the case of long-lived firms, which sometimes continue beyond the lifetimes of the original founders, or of designers with long and varied careers. It will require the development of a more sophisticated data model for the relations between people and firms.

Similarly we hope to more precisely identify professional roles in these relations -- for example, to distinguish a person's early-career work as a draftsperson from later work as a designer. Finally another possibility is to incorporate a spatial dimension so as to identify when people relocated geographically.

Another feature we hope to add in the future is the ability to save the state of a complex graph view, so that you can easily return to the same state without having to rebuild the graph.

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