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Author Topic: Basic couple constraint  (Read 1325 times)

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Offline jamespetts gb

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Re: Basic couple constraint
« Reply #35 on: April 15, 2019, 08:54:24 PM »
The reversal re-ordering is a different issue: the reversing code tests for very specific cases of things that should and should not be re-ordered, and the type of vehicles that you mention are not among those specific cases. If you can add the locomotives in question to a pakset so that I can test, I might be able to add these to the specific case of how to treat reversing if I get the time.

Offline Vladki cz

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Re: Basic couple constraint
« Reply #36 on: April 15, 2019, 10:22:41 PM »
I think it would be better to have the code more generic and not dealing with specific exceptions. There are other configurations that behave similarly. E.g. a DMU/EMU with regular waggons attached at the end. It is a working configuration, but the DMU/EMU loses the very quick reversal, as it has to shunt to the other end, but it should move as-is.  I will prepare a sample - I have the class 131 in pak128.cs, but I ca't get the whole pakset working (see my report a few days ago)

Offline Ranran jp

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Re: Basic couple constraint
« Reply #37 on: April 15, 2019, 10:37:36 PM »
Perhaps the solution to that problem is beyond this patch.

I think the Vladki's example is the same issue as the Japanese articulated electric locomotive I mentioned in my previous post.
At least the current extended does not consider the case where the bidirectional = 1 locomotive is single headed.

For example, this type of locomotive never works properly (if you treat this vehicle as two cars).
https://en.wikipedia.org/wiki/SBB-CFF-FFS_Ae_8/14
Japanese locomotive examples:
https://en.wikipedia.org/wiki/JNR_Class_EH10
https://en.wikipedia.org/wiki/JR_Freight_Class_EH500

I'm convinced that the fixed_coupling is useful to reorder the convoy when train reversing also in the current version.
This is because reordering when reversing is actually a re-combination of outside the depot.
A powered vehicle that is fixed_coupling is considered to be a group, and I think that it is the correct operation to shift together when reversing.

I think that adding new parameters to the dat is not a good idea if it is achieved by a review of the algorithm.




Currently, bidirectionl articulated locomotives are shifted as A by reversing.
It will be able to review the algorithm to make this B.

I guess that the same process can handle Garratt and brake tender.
« Last Edit: April 16, 2019, 04:44:19 PM by Ranran »

Offline Ranran jp

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Re: Basic couple constraint
« Reply #38 on: April 16, 2019, 04:23:15 PM »
One thing that might be helpful once this has been finalised is to put up a post somewhere explaining what each of the symbols mean, with pictures of what each of them look like, in a list format.

This is a clutter job (Including the latest in-game demo), but we can display the legend when nothing is selected.
I'm not an English speaker, so I can't make of an appropriate English text, but I think it's preferable to be as short as possible.

Considering the minimum display width of 64px pakset, it may be better to describe only the shape of the bar.
And add the difference between powerd and unpowerd and fixed coupling thing.


What do you guys think about this?


Quote
The explanation should also be in the in-game help files, although unfortunately I do not believe that it is possible to have pictures in these.
I hope that help text can extend the description in html format for added color description and symbol description.

Offline Vladki cz

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Re: Basic couple constraint
« Reply #39 on: April 17, 2019, 11:24:52 PM »
Here is an example of articulated bidirectional loco. The weirdness is a bit more than what ranran described.
Lets have a train 12ABCD, where 1 and 2 are engine parts, A-D are wagons.
After reversal it should be: ABCD12
However with bidirectional=0 I get: BCDA21, engines facing properly, but log turnaround
And with bidirectional=1 I get: BCDA21, engines facing wrong, but short turnaround
Note that also the first carriage got pulled to the other side with the engines in both cases.

Testing engine attached (diesel)