Options in depots to only show lines passing near a depot in line dropdown

[Nazalassa]

A small patch that allows users to restrict the lines shown in a depot's drop-down line list, to those that have a stop within a certain distance of the depot (currently hard-coded at 42). Useful e.g for urban networks.

[Isaac Eiland-Hall]

The answer to life, the universe, and everything?

[Nazalassa]

The answer to life, the universe, and everything?

Also an empirical constant that is neither too large (showing lines too far away) nor too small (not showing some nearby lines).

[prissi]

This is dictating the players a certain style. I play deliberately with a single depot per network. Since Simutrans cannot guess the player's style, the general rules was to not commit anything forcing a certain style.

Thus, the patch has little chance of incorporation without making it configurable via the GUI and off by default.

It would be different if limiting to stops connected to this depot. But finding this out is very time consuming and non-trivial. And convois with their home depot would not apply for new depots.

[Nazalassa]

Here is a variant which makes the distance configurable on a per-depot basis. (It is not saved with the map though.) Note that it was already disabled by default.