PreSignal
This script adds so-called pre-signals to the game. Using markers, they can monitor route reservations between regular signals and switch to red when needed.
It is especially useful on single-track sections where additional protection signals are needed.
In the signal menu, you can add two marker types: ANY and ALL.
ANY — passage is blocked if at least one ANY marker is reserved.
Place these on a single-track section in any quantity; if even one marker detects a route reservation, the pre-signal turns red.
ALL — passage is blocked only if all ALL markers are reserved.
This is typically used after route-selection/platform-selection signals.
Example: after a single-track approach, there are two platforms; if both are occupied, entry to the single-track section is blocked.
For markers to work correctly, select “Sensor Marker” so each marker acts as a route-reservation sensor.
The pre-signal then reads reservation states from these sensors.
Practical usage examples are shown in the screenshots.
WARNING! This script has some limitations:
– If you use platform exit signals as pre-signals, and a platform-selection signal as the entry signal (as shown in the screenshots), the train must be longer than half of the platform. Otherwise, the platform-selection signal may stop working. I don’t know the exact cause yet and haven’t found a fix so far.
– Route occupancy is checked only at marker locations, so in some situations the pre-signal may fail to detect an occupied route. This can be mitigated by placing additional markers.
