PC randomising rail tracks

[Trimerion]

are there any engeneers who play with rail tracks here? I have found that certain rail joining configurations will sometimes send you on an unexpected rail path but unfortunately im having difficulty nailing down what the confuguration/rules for these joins to give a consistant random result

just finished building a duke arena and I keep getting caught in my initial boost tracks, cutting off the area where those tracks are is an option but I was hoping to find a cleaner solution amongst other people who play with these things

 

[ZeroGravitas]

I keep getting caught in my initial boost tracks

Sounds hard to describe - gifs, vids, images...? When hammering junctions there's one configuration that doesn't actually join the track properly, so there's a little gap, which might conceivably cause you to fall through or not depending on speed. Also, you know that pushing up or down over-rides the default junction direction selection? (Not sure this is even what you are really talking about though.)

 

[Trimerion]

this is my full arena before I put in the boost tracks. At the points where the diagonal meets a horisontal it will occasionally choose the horisontal track in favour of continuing on the diagonal and vice versa its hard to discribe, you are right

 

[Mimp]

When they first added tracks I made a funky set of track switches that would let you go clockwise or counter clockwise around a weird shaped chunk of the underground. There were a couple parts that were mostly vertical so they required a lot of angle tracks with bouncer ends to keep you moving but getting that to work in both directions was tricky. (Forgive my lousy paint drawings, I can't access the game for proper assets right now...)

So as you can see you basically have 5 junctions to manage but they can be static once set up and they work pretty nicely. You have to hammer them like this:

- Top Left: straight track up top, allows traffic coming up to join the rail and head left.
- Top Right: angle down, traffic coming from the right, headed left will go down.
- Bottom Left: straight track at the bottom, allows traffic coming from up top to join the flat rail and head left.
- Bottom Right: angle up, traffic coming from the right, headed left, will go up.


With a logic gate you could do the same thing with pressure plates as a wire on a junction will changes it's function.

If you hold a direction, (up or down,) you can force your minecart to go on a track that intersects but isn't the default direction for you to go, is it possible you're holding a key and causing the weird behavior? Also, which specific junction was causing you grief, have you narrowed it down?

I think I saw a junction or two where the angle track goes behind the horizontal track, those spots tend to work where you'll end up following the track in front. You may need to hammer the junctions a bit more to give the angle tracks priority. The one I'm looking at is the left most track headed like this: /

 

[Trimerion]

this is a smaller version that I built for my skeletron fight, where the diagonal intersects with a horisontal it will sometimes choose the horisontal track, and sometimes the vertical track, my problem is that I cant anticipate when it will choose. also this behavior is without pressing any directional keys whatsoever.

 

[Mimp]

this is a smaller version that I built for my skeletron fight, where the diagonal intersects with a horisontal it will sometimes choose the horisontal track, and sometimes the vertical track, my problem is that I cant anticipate when it will choose. also this behavior is without pressing any directional keys whatsoever.

Ok, so walk me through what this track is supposed to do. I'm guessing you start in the dungeon entrance and go up the angle track? After you hit the top and head left you bounce then go through the pit of honey, bounce on the right and head back up through the honey again, hit the left top bouncer then go back down the angle track again but that time you stop on the next rail and head right then loop up top like that?

 

[Trimerion]

the original design was to start in the dungeon entrance, head to the left, bounce on the horisontal tracks to the top row then take the diagonal back down to the dungeon entrance, creating a loop. what actually happened is that every 2-4 loops I would end up bouncing along in a much smaller loop in the top 2 rows, the rest of the time it worked as intended

 

[Talrey]

I think I see the issue. Minecarts always prefer the "top-most" track when at a junction- this means that the track that appears continuous will be the preferred choice, and a track that's "behind" it will be secondary. Counting with 1 as the ground track in your layout, the diagonal is "on top" on layers 2, 3, and 5. TBH I'm surprised you even get to the top layer on the horizontals, I'd think you'd hit the diagonal on layer 3 and go straight up from there. You won't have any issues on layer 2 because you're going away from the up part of the diagonal, and the down part of the diagonal is the secondary track (see how the corner curves up?). On layer 3 though, you're heading towards the up diagonal, which has layer priority (it's on top).

As for how to fix the issue, I'm not sure. I've only experimented a little with rails so far, but four-way junctions seem rather tricky. My advice would be to scrap the diagonal entirely, and have each layer use two of those zig-zag bumper parts. You'd have to hold down (or up, depending on how you've hammered the tracks) to change layers sometimes, but it would be predictable behavior...
[DOUBLEPOST=1441827754,1441827391][/DOUBLEPOST]Actually wait, I think I just thought of a solution that would let you keep the diagonal. Give that rail priority by hammering the junction, then add a second junction just above the first where down is the primary choice. That way you'd stay on the horizontal or diagonal with no problems. Here, I'll do a quick picture of what I mean... [edit: trickier than I thought. Got it working one direction, but not the other. A "smart" junction using plate tracks would be a lot easier than a static one if you have wire.]

 

[Trimerion]

You'd have to hold down (or up, depending on how you've hammered the tracks) to change layers sometimes, but it would be predictable behavior...

that would make sense except that using directional keys to switch tracks at high speed often does not work, but as for your explination of the track switching, that makes a lot of sense, although sometimes it will choose to travel on the secondary (behind) track, im trying to figure out what causes that behaviour

 

[Talrey]

Oh, I see. I'm not sure then. It sounds like a glitch to me, but I'm by no means an expert on these matters.

I have, however, "discovered" that an X-shaped intersection hammered correctly does what you're trying to do. I've tested it in a mechanical cart with bumpers for repeat testing and I haven't been put on the "wrong" track yet. You could do something like this for your junctions, then. There's a little wobble obviously, but it shouldn't affect aiming much...

 

[Trimerion]

lol @Talrey im not trying to eliminate the behavior, im trying to increase it byt yes an X shaped track will always follow the path you are on

 

[Talrey]

@Trimerion then I guess I'm completely misunderstanding the question, haha. Sorry

 

[Stahn Aileron]

Just a question: Did you know that junctions can be controlled with wires and switches/pressure plates? You could use some wires and Pressure Plate Tracks to control the junctions as you move across the system. I'm bored right now (taking a break from Kerbal Space Program; just got back into it during my break in school), so maybe I'll pop into Terraria to slap something together.

EDIT:
A) You need the Mechanic for the Pressure Plate Tracks and wiring tools... =_= So useless pre-Dungeon...
B) It does work though ^_^ So it'll work for your Duke fight.

Spoiler: Track Setting

Spoiler: Wiring

(Ignore the blue wire: that's a teleporter line from my base to an arena zone.)

The red wire touches each junction point. Each end on the red wire has a Pressure Plate Track (which can't be set diagonally, hence the short horizontal lengths on that diagonal return line).

It worked for me perfectly, though there was a short-lived glitch I didn't replicate once it disappeared (I would some times return from track 2 and 4, 1 being ground and 5 top.) Might've had to do with travel speed since I used a MechCart. I slowed down a bit to test. Working fine for several loops. Sped up and didn't have a problem again.