AI Approaching Junction

[shaneturner12]

Fair enough - I do know, though, that by default trains are Priority 2.

Shane

 

[Mick_Berg]

I'm sorry, but you are both wrong. Priority doesn't have a highest or lowest.

All it means is that if the track is set for one priority (e.g. P1) then a train with priority 1 will try to use the P1 track rather than other priority tracks.
If the track is not clear then it will choose another one.

Trevor

Finally, a meaningful explanation!

Question, if you put a priority mark on a track, for how much distance is it in effect?

Mick Berg.

Thanks,
Mick Berg.

 

[Mick_Berg]

Okay since my idea of adding invisible signals seems to have worked and you want to add Distant signals try replacing the invisible signals with Distant ones. You might want to adjust distance between Distant & Home signals depending how close/far apart they are.

Pete

Good idea, thanks Pete, but only for some. If I changed all the Invisibles to Distants there would be way too many.

Nickb4a, my apologies, I seem to have hijacked your thread, but there is some good stuff in here!

Mick Berg.

 

[Mick_Berg]

Hi Mick,

Could it be that where the train leaves the main line there is a shorter way to it's destination? The AI will always take the shortest route unless it is prevented from doing so by a drive via trackmark command. This goes right back to trainz 1.3.

Cheers,
Bill69

Thanks Bill, but you'd think that the main line would be the shortest route, as it's straight track. Where the train "veers off", the distance is surely more, if only by a tiny amount.
Mick.

 

[Bill69]

Thanks Bill, but you'd think that the main line would be the shortest route, as it's straight track. Where the train "veers off", the distance is surely more, if only by a tiny amount.
Mick.

Well Mick, as I see it you have two options to keep the train on the main line. Option 1 for me would be to place a trackmark on the main line about 100 metres past the junction that is allowing it to veer off. Option 2 would be to make the side track either priority 1 or priority 3 and leave the main line train at the default of priority 2. Using the priority markers you can direct other trains to use the main line or the side line by changing their priority and not changing anything on the route.

Cheers,
Bill

 

[Mick_Berg]

Well Mick, as I see it you have two options to keep the train on the main line. Option 1 for me would be to place a trackmark on the main line about 100 metres past the junction that is allowing it to veer off.

Yes, that's what I have done. But what I'm trying to get at is, why does the AI choose to change the junction at all? When I look at the route in Surveyor, the junction is set to the main line. The next destination is on the main line. Why does it change it?

Option 2 would be to make the side track either priority 1 or priority 3 and leave the main line train at the default of priority 2. Using the priority markers you can direct other trains to use the main line or the side line by changing their priority and not changing anything on the route.

Are the side lines other than priority 2? If not, that would need a change in the route. But I'm working on a completely different route. It is based on ECML, but it has been massacred! All the catenary is gone, all the AWS triggers, the signals are semaphore, and it ends at Stevenage. If I could only get merging to work, I would add my Alexandra Palace branch and my Widened Lines. (Which, if all goes well, will be part of a future ECML update.)

Mick.

 

[Kennilworth]

Hi

With regard to the AI turning onto the slow line I found that this happened usually on a curve. If the line curves then the slow line could be a few yards shorter than the fast line which may cause the AI to decide to use it.

Regards

Brian

 

[Mick_Berg]

Hi

With regard to the AI turning onto the slow line I found that this happened usually on a curve. If the line curves then the slow line could be a few yards shorter than the fast line which may cause the AI to decide to use it.

Regards

Brian

Bill69 suggested this as well.

You may well be correct. I see now that this part of the line is indeed on a curve, and the route that the AI chooses to take is on the inside of the curve.

But now with a few strategically placed trackmarks, and about 800 invisible signals,:hehe: things seem to be working as I want.
Thanks,
Mick Berg.

 

[trev999]

Question, if you put a priority mark on a track, for how much distance is it in effect?

Answer: I don't actually know for sure but at a guess, until the ID of the track changes, which would be at the next junction or perhaps (grade)crossing, or point where the track direction is reversed.

Trevor

 

[Mick_Berg]

Answer: I don't actually know for sure but at a guess, until the ID of the track changes, which would be at the next junction or perhaps (grade)crossing, or point where the track direction is reversed.

Trevor

Well, Trevor, I surely hope you are wrong! If they are only effective till the next junction, you'd need hundreds of them to keep a track at a certain priority in any decent sized route.

I would suspect it stays the same until another priority trackmark of a different value. But I would really appreciate a definitive answer, maybe from an Auran person?

Today I'm going to make a test route to determine the number of signals needed (or the minimum distance between them) to keep the route open. I'll also try to devise a way to find out exactly how the priority markers work.

Thanks,
Mick Berg.

 

[shaneturner12]

To add to that, you may need to add an extra one or two at stations.

Shane

 

[trev999]

Well, Trevor, I surely hope you are wrong! If they are only effective till the next junction, you'd need hundreds of them to keep a track at a certain priority in any decent sized route.
QUOTE]

In my opinion, the priority marker is really only intended to assist the AI driver in choosing the path through one junction. Once the junction has been passed the marker is ineffective since another ahead junction could lead to anywhere. Just because a length of track is straight does not mean that the priority should be carried over from one section to another.

There are ways of determining the priority of a given piece of track by script code and I will make some tests and report back when I have a bit of spare time.

Cheers - Trevor

 

[Kennilworth]

Hi

The track prorities show up in different colours on the map in driver so try adding just one track priority marker in surveyor then have a look at the map in driver to see how far the colour extends. I can't remember what the colours are now.

Regards

Brian

 

[trev999]

Facts about Track Priority

Hi

The track prorities show up in different colours on the map in driver so try adding just one track priority marker in surveyor then have a look at the map in driver to see how far the colour extends. I can't remember what the colours are now.

Regards

Brian

Hi Brian - You are a Star. I have been working with TRS2004 for at least five years and never realised what was changing the track colors in the mini-map.

I have collected the following facts about priority markers:

* Track priority does not extend past a junction or industry.
* It does not change when the track direction is reversed, or on encountering a grade crossing.
* The color of priority 1 track is green in TS2010 and orange in TRS2004.
* The color of priority 3 track is cyan or turquoise.
* The priority of any track can be determined by using the properties button on a priority marker object.

Cheers - Trevor

 

[Mick_Berg]

You guys are geniusesssss!
Thanks for all the great info. No need for me to do my test now, and anyway I doubt if I would have come up with all those findings on my own.

EDIT: Actually I did make a test route, and it's very educational.
It seems that, indeed, the boundaries of the priority marker are junctions.
The marker can be placed anywhere between two junctions and that stretch of track will have that priority.
Priority over-rides the "Shortest distance" rule.

I'm surprised that there is no option for "no priority" for a vehicle, (you'd think it would be "priority=0").

Happy Holidays everyone,

Mick Berg.