Collisions

[AP]

Time interval signalling
...
- If trains collide in this method, both trains will come to a stand for a long time before continuing in the drive by sight working method

Is the intention then that in-game collisions are now being simulated? This would seem to be quite a change from previously, where everything has been 'perfect' in that regard.

Presumably it opens a precedent to other similar issues - periodic mysterious loss of shipping / due to piracy or poor navigation (or icebergs) , road traffic accidents, air crashes, etc.  Indeed if you simulate one but not the rest you give an undue advantage to the perfect systems over the imperfect ones.

[jamespetts]

The idea is that what is simulated is not a collision, but the consequences of (perhaps narrowly) avoiding one. The rule in the days of time interval (and, indeed, many years beyond) was that, if a train made an unscheduled stop, the guard (or under-guard) would have to walk back along the line and fix detonators to the track at specified intervals behind the train to warn approaching trains to stop. The simulation assumes that this has happened, and that the train in rear manages to stop just in time without an actual collision, but that both trains need some time for their crews to assess the situation before they are put on the move again, both in drive by sight mode.

Thus, the principle that mishaps are not simulated in Simutrans has been maintained.

[NoMorePacers]

Collisions are generally quite graphic, and would require a lot of coding and graphics designing, creating and editing them. Simutrans is different to OpenTTD in that the latter is based on a commercial title and the base engine is essentially that of Transport Tycoon, which was a commercial title. Simutrans was written entirely from scratch and has always been free and open source. OpenTTD is free and open source, but until about 6/7 years ago, required TTD to run, which was paid for and closed source.

[AP]

The idea is that what is simulated is not a collision, but the consequences of (perhaps narrowly) avoiding one. The rule in the days of time interval (and, indeed, many years beyond) was that, if a train made an unscheduled stop, the guard (or under-guard) would have to walk back along the line and fix detonators to the track at specified intervals behind the train to warn approaching trains to stop. The simulation assumes that this has happened, and that the train in rear manages to stop just in time without an actual collision, but that both trains need some time for their crews to assess the situation before they are put on the move again, both in drive by sight mode.

Thus, the principle that mishaps are not simulated in Simutrans has been maintained.

I'm unsure what value this simulation detail adds in gameplay terms?

If you're simulating "near misses" the same would apply to other forms of transport too - ships anchoring in dense fog (more prevalent at certain times of the year), delays from drivers shouting at each other at road junctions. 

[Rollmaterial]

I'm unsure what value this simulation detail adds in gameplay terms?

If you're simulating "near misses" the same would apply to other forms of transport too - ships anchoring in dense fog (more prevalent at certain times of the year), delays from drivers shouting at each other at road junctions.

It's an inherent feature of the time interval working method. It's meant to reflect the limits of what was feasible in the early times before the telegraph was introduced and allowed for absolute block working.

[jamespetts]

Rollermaterial is correct - time interval signalling is inherently vulnerable to collisions (or near misses), and so the game has to do something about what happens when this occurs.