Train repeating signal

[Nethanek]

Brief:
Train repeating signal with binary state that repeats signal of next semaphore in simple manner. It represents two states: "next block is free" and "next block is occupied".

Problem:
John have two distant bases (Amurica and Bahrain) connected with railway. He's using train to move from Amurica to Bahrain and obviously goes full speed. Unfortunately he's going too fast to notice next block is occupied and brake on time, so he crashes into train on halt in next block. Everyone dies and cargo of gas is exploding destroying last forest nearby. Could we avoid that catastrophe? Yes, we could!

Solution:
John would have enough time to brake if he saw signal repeater before proper semaphore. Signal repeater is basicly railway signal that represents two states. Base state (green or no light) means "next semaphore allows you to enter its guarded section". Warning state on other hand (yellow light) means "next semaphore has stop signal so you should slow down". Repeaters repeats signal only of one semaphore. It should not work if there are two semaphores simultaneously ahead.

References:
1) Two color repeating signal (here: yellow signal means next signal is red; otherwise it would be green).



2) One color repeating signal (yellow signal means next signal is red; otherwise it would be turned off)




Other possible solutions:
1) John should have watch minimap. Unfortunately it breaks immersion.
2) John could also see normal three signal semaphore with yellow light (as on image below). Unfortunately, factorio uses yellow light to mark section reserved by AI.

[steinio]

Yeah if we had a chain signal...

[Nethanek]

Chain signal makes you stop if it's red. Repeating signal does not - it's just a warning.

[Loewchen]

You are trying to solve a problem that simply does not exist in this game, trains do not need to "see" signals, they are driven by a centralised algorithm that knows any occupied block in any trains path and will not allow for it to enter such block.

[Nethanek]

The problem does apply to players in trains, not AI.

[FuryoftheStars]

The problem does apply to players in trains, not AI.

While this is true, the size blocks that a player can place vary in size. Plus would this essentially be another item that you’d have to lay down at every signal so that you can have your whole line covered? It’s better not to drive manually on a line with other trains on auto. It’s too dangerous for obvious reasons.

[Nethanek]

Of course it's dangerous, that's why I propose a tiny safety measure Also riding trains is fun.

[sepharim]

You could place a lamp next to the train and connect it via circuit to have the same color as the signal it's repeating. So it will be easily identifyable as "User Pre Signal" . If you really really want it

[FuryoftheStars]

You can ride them without driving them.

Anyway, point I was trying to make with the blocks being of variable size is that a train can take more than a couple blocks to stop if the blocks are set small enough, meaning being warned what the next block’s signal is may not be enough. How quickly a train can stop changes, too, between how much weight it’s pulling and how far down the braking tech you’ve researched. This makes this item difficult to use and it depends on the player placing it correctly.

I think what I’m trying to say is, while I understand why you want it, I believe it would be difficult to implement, not because it’d be difficult to code, but because depending on the individual player’s train network and current tech, being warned of the next block’s state may not be enough.

[Darinth]

So the problem is "When I manually drive trains, I might not realize that there's a train parked in front of me with enough time to stop." you want a solution that provides more time to stop. I can sympathize with this... but to be real blunt manually driving trains is dangerous, no matter what you do. This becomes more and more true as you get more and more trains on your line. I feel the proper solution to this, and I know this isn't what you want to hear, is to stop driving trains automatically. What you're suggesting would be a bandaid at best. Even if this were implemented, you're going to still have problems with fast moving trains 'cutting you off', because your manual train doesn't reserve blocks in front of it, which will result in you crashing into trains at intersections. Manually driving trains is dangerous. I suspect that's part of the motivation behind the ability to be able to route trains to arbitrary locations via the temporary trains stops in 0.17.

[mrvn]

I feel that with the temporary stations driving trains manually is nearly a thing of the past. I only do it now when I need to drive against the flow.

That said the repeating signals would simply be a lamp connected with a wire to the next signal. A bit more tricky to build if the next signal is a chain signal but still doable with a few combinators.

[Tekky]

So the problem is "When I manually drive trains, I might not realize that there's a train parked in front of me with enough time to stop." you want a solution that provides more time to stop. I can sympathize with this... but to be real blunt manually driving trains is dangerous, no matter what you do. This becomes more and more true as you get more and more trains on your line. I feel the proper solution to this, and I know this isn't what you want to hear, is to stop driving trains automatically.

An alternative would be to introduce a new mode of driving trains, a semi-automatic mode. This has been suggested in the following threads:

viewtopic.php?f=6&t=42694 Half automatic / half manual train driving
viewtopic.php?f=6&t=49850 Locomotive mode: Manual with assist

Related threads:

viewtopic.php?f=6&t=62272 Mitigating the dangers of manual train driving
viewtopic.php?f=6&t=53533 Manual trains, predictions?

[Darinth]

An alternative would be to introduce a new mode of driving trains, a semi-automatic mode. This has been suggested in the following threads:

viewtopic.php?f=6&t=42694 Half automatic / half manual train driving
viewtopic.php?f=6&t=49850 Locomotive mode: Manual with assist

Related threads:

viewtopic.php?f=6&t=62272 Mitigating the dangers of manual train driving
viewtopic.php?f=6&t=53533 Manual trains, predictions?

I like the concept of the 'assisted manual'/half-automatic, but I don't personally think it's worth the effort to put in to it when we now have the ability to arbitrarily pick spots on a map and go to them. It really depends on demand for such a feature.

The 'mitigating the dangers of manual driving' thread I don't care much for. It's a very limited situation, in fact I don't know that I've ever been rammed by a train. Though I've rammed my own trains a few times. Thus why I don't use manual mode any more. Maybe I've just been lucky on this particular front.

The concept of 'manual train predictions' would more or less have to be a component of an assisted manual mode. Which as I said, I like the concept of... but I think we've got better now and I'm just hard-pressed to see it as useful. But it depends a lot on the demand for such a feature. Just how much of factorio's players really want to be able to drive trains in manual mode? I suspect it's a small subsection. 'Manual' is kind of contradictory to the mindset of playing factorio, a game about automating everything.

[mrvn]

There might be a game mechanic for repeat signals after all as follows:

Repeat signals are a mix of signals and chain signals with 4 colors:

1) green - all ways are clear
2) blue - some ways are clear
3) yellow - block is reserved
4) red - block is used

Like chain signals a train will try to reserve the segments following a repeat signal until it hits a signal or reservation fails. But unlike a chain signal a partial reservation is just fine and the train will continue until it has to stop at a red signal. So it's a soft reservation. When a segment becomes free any train from a repeat signal should get first dip at reserving the segment too.

The use of this would be to prioritize high speed tracks by allowing trains on those tracks to reserve crossings ahead of time without causing them to stop early when reservation fails. That means other trains can't bock the crossing if a high speed train is approaching but also trains on the crossing might manage to clear the crossing before the high speed train absolutely has to stop.