Set the probability that towns will build roads.
2.0.1 alpha 49 or later
Configuration file: townroadbranchprob on|off|<prob>
Command line: (none)
When expanding, towns normally have a 40% chance of building a road branch (as opposed to a building). With this switch, you can control this probability from 0 to 65535=100%. If set to "on", a probability of 21845=33% is used.
When set to zero, towns will only extend existing roads and never build any road branches, so that they end up with one long winding road. If this road winds up back on itself, road building will stop there because the town needs to build a branch to build more roads. Of course you can help the town by adding such a branch manually.
For values below the default, TTD towns will generally have fewer road tiles, which usually means that there are fewer places to construct buildings, and as a result the town may grow more slowly as well, unless you add more roads manually.
This feature was contributed by Csaba Varga.