Collisions between trains on adjacent tracks

[PWHolmes]

I have a strange problem here.

I have created a scenario that requires a train to wait in a siding two tracks away from the main line and an AI train to pass on the main. When they are level with each other although they are separated by an empty siding, they collide and derail. I have tried swapping one of the locos and it still happens.

When I move the loco in the sidings 200m down the siding, the collision moves with it!

What is causing this? Any ideas anyone??

Paul

[Kromaatikse]

Which two locos? If they are both default or Steam based (or you can reproduce it with such), report it to support@rsc.

[Kariban]

Heh, there's a fun thread at RWA about strange collision detection; one guy's parked train appeared to hop over a building and land in the carpark.

The collision boxes are a bit huge in the editor:

http://www.youtube.com/watch?v=YE2JNFHyPJg

I wonder if they're actually that huge in the game itself.

[PWHolmes]

Sorry about the delay in getting back - been busy at work!

I have reproduced this fault using two default deltics (I use these the least and know for certain I haven't downloaded extra locos from UKTrainsim).

See attached screenshot - the loco on the freightliner came to a jarring halt when level with the front of the loco in the loop.

[Kromaatikse]

The track spacing on that route is very narrow - akin to the original Liverpool & Manchester arrangement, which was designed so that a wide-load train could run down the centre of the line, using one rail of each track. Modern stock will certainly be out-of-gauge on it.

Can you reproduce it on a default route, or one with more modern and sensible track spacing? Modern terminology says "four foot" for the space between the rails, and "six foot" for the space between the nearer rails of two adjacent tracks, to give you an idea.

[PWHolmes]

Sorry, Kromaatikse but that cant be right.

The route in question is a heavily modified IoW with a colliery at the end of the branch and a goods yard where Ryde Yard now is but on the other side of the line. The track spacing is standard IoW. Also, I have got AI trains to pass on the double track sections and I have shunted alongside without problems in other scenarios. In addition to this, I get a collision when a main line train passes a rake of MGR wagons on the second road in (eg with an empty track between them).

Something wrong here, surely??

[Kromaatikse]

The track spacing is standard IoW.

That in itself means nothing - it only affects track laid using the multiple-track tool, which I suspect was not used for IoW itself (since it doesn't have much double track).

When RSC get your bug report, they will immediately want to replicate it on a default route. You need to ensure that they will be able to do this based only on the information in your report. And, if you *can't* replicate it in a default route, you will need to look into what is different about your own route which is triggering the problem. In that case the narrow track spacing would be one of the first things to investigate.

[PWHolmes]

Well, after an afternoon's continuous experimentation I think I can reliably say I have bottomed it.

I can make the Freightliner pass through without problem by removing it from the start portal and placing it on the track immediately outside. As soon as I place it inside the portal the above problem occurs. I have tried this repeatedly with different items of rolling stock. Starting outside the portal passes through without collision even with stock on adjacent roads, starting INSIDE the portal it collides with stock 2 tracks away with an empty siding between!!

Can anyone explain that??

[Gatso]

...it collides with stock 2 tracks away with an empty siding between!!

Can anyone explain that??

The same thing happens with the Horseshoe Curve route. Have two trains passing on the main curve either on adjacent tracks or with an empty track between and there's an AI collision. It happens using American or British trains. I've reported it to RSC who seem unsure what it is.

Earlier replies on this thread suggested it could be the track spacing but as British rolling stock is narrower than American that must surely rule it out. It's annoying because one of the reasons I purchased that route is to have several trains passing on the curve with their flanges squealing.

[Kromaatikse]

If AI traffic is coming out of portals, then that is a potential explanation. Exiting portals is an unsupported feature - if it breaks we get to keep both pieces. It it known to have at least some glitches, and this might just be another of those.

Entering portals is fine.

Can you reproduce the problem at all without having any train exiting a portal?

[PWHolmes]

No - exiting portals only.

Maybe I will add fiddle yards instead.

Incidently, I have other routes where trains exit portals no problem.

[Kromaatikse]

Possibly the orientation of the portal (or the track it's attached to) matters. This isn't something I plan to investigate myself.

[justgeoff]

I don't want to 'muddy' the waters here but I had a similar problem on South Devon Banks and by the process of elimination/substitution I found it was one item of rolling stock in a consist. Even though this item was at the back of the consist and therefore furthest away from the two locos, the appearance was that the locos were in collision.
I remember in MSTS there were things called 'bounding boxes' which could cause this sort of problem, is it the same for RW?

Cheers,

Geoff