You can read the full story here: viewtopic.php?f=214&t=51201 A perfect combination: Using Train Builder and Train Destructor
But I have put some energy into it, thinking about how that could work in vanilla and I found it too sad to loose that all. So here my suggestion:
Assumend I would have had time to program such a mod (*) that combines a train-builder/destructor which does not work like "magic", I would build some kind of large structure over the rails. On top of that a crane would drive back and forth (when building in anti-direction of train, when destruct in direction of train). So - logically - I can build/deconstruct trains only in the coverage of that structure and building/destructing takes some time, depending on speed of that crane.
I think it can look similar to this:
So the "rails/road" for the crane are modified rail-signals (that look like small road/single rails).
A modified car sits on top of that - as the crane - and would move along, so that a "build/destruct" would look like a movement of the crane.
On map it would look so:
Code: Select all
Pseudo-vehicle as crane over rails
v
< < < < < < < < < < < < < < < < < < < < < <--- new type of rail signals (<)
-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-###+-+-+-+- <--- rails
-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-###-+-+-+-
> > > > > > > > > > > > > > > > > > > > $ <--- new type of rail signals (>) and train stop ($)
# # <--- requester and provider chests
- The signals look like a road/rails for the crane (see pic). [signals are needed to ensure, that the area you want to build is really free in the moment you want to build]
- The crane moves on that rails back and forth and pics up the locos and wagons out of the requester chest or puts destructed items into the provider chest. Whatever this will look is implementation detail.
- The crane begins to build when the first matching item arrives - and so on. The longer the train, the longer it takes to build it, cause of the length that has to be moved back and forth.
- The whole structure (signals, stops and chests) belongs together.
- Removing the stop removes all. Maybe with some kind of safety question.
- You can extend "signals" at the end at (nearly) any time to create longer trains.
- The order (what to build/destruct, how to program the train) is done (more or less completely) by circuit network. I won't describe how that could work here, but I think it some ideas of the train builder mod are good and some are not so good
(for example: with train builder you cannot build trains which have two locos in one direction).But there are of course some "general" ideas, like:
- A train is only built, when really needed - maybe controllable over the train stop.
- If a train is built or destructed is decided via circuits. For example: positive value on "build train"- signal means build, negative means destruct. Zero means: Do nothing and work like a normal train stop.
- what is built on which position could be encoded just by setting the rail-signals to the right item-type (via circuit signal). Makes the composition simple and understandable: In the simplest case just place a constant combinator to every third rail-signal that emits the item-type of the wanted train-part. That would also enable to encode the direction of the loco in a very simple way. That makes it also compatible to mods, which have shorter length of loco/wagon.
PS: I wrote it so, that it would be possible to create a mod out of that description, but I put it into Suggestions and not Mod-requests, cause in long terms I would like to have some kind of support for large constructions in the vanilla game: Constructions, which belong together over some rules. Maybe I will explain that idea also here, cause I think that would make Factorio really fun.
(*) which I haven't; currently I'm working on a mod, that does a completely new way of radar
More pics:
Another option: Crane is fixed and train moves under the construtor until completed:
