Is It Really That Hard To Make Ai Follow The Signal Speed?

It's annoying when AI flies up to a stop signal at supersonic speed. When a commuter train on LIRR is rushing towards you from behind.
Is it really that hard to make AI follow the signal speed? When passing a signal with value X, reduce the speed to value Y until the next signal. Is this some lost technology of Atlantis, or what?
How much more realistic will the route simulation become after adding this simple feature!

 

What makes it worse is that the timings on many routes are based on AI, which makes it impossible if you're actually driving legally.

 

AI probably runs with simplified physics, just like in TSC. Maximum acceleration and deceleration as defined by the speed curves.
Only the loco is 'visible' to the system, train length doesn't matter at all.

It is disappointing though, from TSW 'ultimate in realism' one expects better ...

 

Ultimate in realism, hahahahaha. I had to give you a like for that, very droll.

 

Yes. But AI can perfectly follow the line speed. it even struggle going uphill on some routes.
AI sees a stop signal. So why can't it see other signals that would give it an instruction to reduce speed?

 

Honestly, yes.

On German (and similar) systems, where the end of the area in which signal speeds apply is depends on what type the signal is topologically. At station entry and station intermediate signals, signal speeds apply until the next signal OR until the place where the train is making a scheduled stop. After any other signal, signal speed applies until the end of the following "points area" (not quite the same thing as an Interlocking...). I believe the US has similar aspects where one speed applies through an interlocking and then you can speed up.

All perfectly possible to implement, but the game currently has no concept of what an entry signal, intermediate signal, or a folliwing "points area" actually are. So you'd have to add this on a route by route basis, adding the necessary data for every track and signal, even after adding the necessary systems to the game. This would probably only ever happen on new routes going forward, and not the back catalogue...

Would be nice of course, and it's obviously nowhere near impossible, but it's very much not just "silly DTG forgot to set the 'follow signal speeds' tickbox to on"

 

I'm not asking for a full and accurate simulation. I just want the AI trains to stop rushing towards red signals and on occupied sections(for example, LIRR).

 

The ai trains and services don't have simugraph. If every ai train and service had simugraph, the memory usage would be through the roof and make the sim unplayable on all systems.

 

Not entirely. The system knows to change signals when the end of an AI train clears a block, for example. and I believe AI does wait for the whole train to pass a speed increase sign before accelerating.

 

Signal speed limit has nothing to do with simugraph physics though.

The game already checks the signals even for AI trains (otherwise they would run through reds). Making it so restrictive signals actually make them reduce speed wouldn't be that hard or any more performance heavy. No need to simulate the safety system in details. But every signalling system could easily have "this signal aspect means this speed limit" value sheet which makes AI trains slow down.

 

As an aside there is an ongoing inherent issue with speed signalling based systems (such as Germany) where the sim only enforces the restriction according to track speed definitions, e.g. at the actual points or crossover not passing the signals which is where it should apply from. Players can of course decide to follow the correct procedure and ensure they are down at the required speed at the signal but presumably AI trains brake at the last minute for where the track defines the speed limit.

A major error in a so called simulation, particularly as TSC and Zusi do it correctly. In fact I’m surprised the likes of TSG haven’t taken DTG to task over the matter.

 

And on US routes AI doesn't even pretend to obey signaled speeds, just blowing through interlockings at 79 or whatever since the game has no "line speed" there