Normally, the NetCon diagram is a purely topological representation of the network. That is, it is simply a schematic that does not show any information relating to geographical position such as orientation and length. The Link Lengths View is intended to make use of the length data that is stored for each link, to show each link at its real length. In this view, a scale indicator is shown at the very top of the diagram, and all lines are drawn relative to this scale. (You can adjust the scaling via the Options screen.) This is not possible in the normal view, because there is usually much more ‘clutter’ on the screen in terms of stoplines, arrows etc. Clearly the diagram cannot show the physical sizes of the junctions, but you can set these globally by adjusting the Node Size option in the Options screen.

NetCon itself has no way of knowing how links are positioned relative to each other, so it is up to the user to set these. To do this:

  1. Make sure the TRANSYT data has link lengths specified for all links
  2. Switch the NetCon diagram to Link Lengths view
  3. Turn on the Link Lengths icon on the toolbar to show yellow bars on all links. The yellow bars are proportional to the real link lengths. If a link has a bend, the length is measured along the bend.
  4. Use the ‘Relative Link Length’ option in the Options screen to roughly set the scaling
  5. You must now adjust each link by moving nodes so that the yellow bar touches both the entry and exit node of the link. In other words, the thin black line of each link should not be visible, and no node should be ‘on top’ of a yellow bar. NB: This is significantly easier if you know what the network should look like!
  6. When all links have been adjust in this way, the diagram on the screen is as true a physical representation as is possible. There will be any number of ways to make the links the right lengths (i.e. it may not match an exact street layout), but the point is that the lengths are shown as physical distances.
  7. If you want to move a group of nodes around, you can use the freeform selection tool to select one or mode nodes, and then move them as a group. (The Rotate and Adjust Node Spacing tools also work in the same way.)

The advantage of doing the above process is that results such as queue lengths can instantly be visualised, as if drawn on a map. (Queue lengths in Link Lengths View are shown as distances in metres rather than as proportions of the link. These are obtained via the TRANSYT formula connecting link length, sat flow and link capacity.) This is helped further if you add a background image map to the network. It is also useful when viewing other data such as signals and routes.