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I wonder if it wouldn't make more sense to separate track type and electrification types, so that you could have both 3rd rail and catenary on the same track without requiring all possible combinations of track, 3rd rail, catenary and 3rd rail+catenary being separate track types.

> [separate track type and electrification types]

Yes. Like I pointed out some posts before, an octal system wouldn´t be sufficient if each and every track speciality would need its own slot. But even when dividing the electrification type from the track type, problem remains how to arrange the whole system best and how to implement those mutual dependencies, patch-wise.

Well, IMO this is much too detailed, ATM.

regards
Michael

Patchman wrote:I wonder if it wouldn't make more sense to separate track type and electrification types, so that you could have both 3rd rail and catenary on the same track without requiring all possible combinations of track, 3rd rail, catenary and 3rd rail+catenary being separate track types.

Yes, I think it'd be the best solution... I already proposed it one page ago

It's nothing I haven't think about already.

The question is really to make it code wise as easy as possible and fast enough...

We could generally add a Locomotion like system, so you can upgrade the 3 base types.
E-Rails would be converted on loadtime to be tracktype 0 with catenery upgrade. (and later extend to have actually 0..7 track type slots)

A Locomotion-like system would be best.
OTOH, one should even take into account that some electrification types might be incompatible with each other. For instance, 3rd rail could work together with anything else, but something like normal and threephase catenary couldn't be built on the same track simultaneously.

Snail wrote:A Locomotion-like system would be best.
OTOH, one should even take into account that some electrification types might be incompatible with each other. For instance, 3rd rail could work together with anything else, but something like normal and threephase catenary couldn't be built on the same track simultaneously.

won't that complicate things too much?

The idea that a track tile consists of ground, track and electrification is nicely uncomplex.

Select track Type:

Narrow Gauge, Normal, High Speed

<===>

Select Electrification Type:

None, Overhead Catenary, Third Rail

---

Like that?

Obviously depending on the set, the graphics would be different..?

I think that an end to the third track type being exclusively for third track type trains is what is most needed (however it is decided to sort that out).

<babbling type="stream of consciousness">

There are four bits, right? I just don't think that'll be enough to do the track+upgrade system; as four track types (TTD has three, so we can't do just two track types) take up two of those bits, leaving only two more for the various upgrades, meaning only two upgrades are possible. In this thread alone, we've already discussed at least three different upgrades (catenary, third-rail, and three-phase catenary)

...

Actually, how impossible would it be to use the current four bits for track-type, and use another 4-8 in L8 for the upgrade bits. Or maybe just use three of the four for track type, and use the fourth, and some from L7 or L8 for upgrades?

</babbling>

Since each train GRF is comprehensive, it can set the track types that it wants to use, with out fear of conflicts from another set, and it seems like it shouldn't be too hard for each track type to have its own set of upgrades.

As for incompatible upgrades, that could be satisfied with a callback for the track type that had access to the current upgrades and the desired new upgrade.

TTD has actually only 3 bits free that means 8 possible tracktypes. (yes, it doesn't work in bits)

Storage is not a TTDPatch problem. We can alloc some MB of Memory if we like for landscapes ...

- Sidenote: However I already have a different scheme which needs some work to actually test in game (newmaparray) which allows height based storage aswell. (and doesn't store stuff on titles which doesn't need it) -

The question is simple how to make it internally work. If we limit to 8 tracktypes we could use the gui we have. (Compatible bits explains what tracktypes are compatible to each other)

I don't really think that it's necessary to support different types of overhead caternary in the same game. Yes, I realize that they do exist, and are sometimes used in the same area; but multi-mode trains are common enough now that operationally it would make little difference. Also, how would you tell them apart?

Can someone explain the concept of three-phase catenary to me?

Yes, threephase catenary wasn't used so heavily in most countries.
But it was used in Italy for instance, and quite intensively. Since that country had very little coal supply, electrification was needed very soon, and unlike Switzerland, the threephase system was chosen at first.

This meant that, until the Thirties, the entire country saw a massive threephase electrification effort. That type of catenary was built and engines supporting that type of power were designed and constructed. At first, it gave quite a few advantages (for instance, the engine worked in such a way that the full power was always available, regardless of the speed, so it didn't decrease as the train was speeding up) but soon it started showing its limits (for instance, the engines had to travel at fixed speeds, making high-speed trains unfeasible: usually the limit was set to 70, meaning that trains could only run at 70 km/h in "full speed" regime and 35 km/h in "half speed", all other speeds being impossible).

The threephase catenary was *totally* different from the direct current (courant continu) one. Not only was the voltage different: it also had two wires instead of one. In the game, the graphics could be different.
Of course, no direct current train could run under a threephase catenary, nor the opposite. (in other words, no multi-mode trains were possible. Apart from diesels, of course )

After WW2, new, more efficient direct current engines were developed, and soon the threephase system was doomed. So the country had to go through a slow and painful conversion of most of the overhead wires across the main lines. Of course, all of the old engines had to be set aside.

Again, this was particular of Italy, but since I am planning to do an Italian set sooner or later, I would strongly like that this feature be implemented in NewRoutes in some way. I cannot imagine an Italian set without it.

If this can help, that set will have no 3rd rail system (it was never really used on the southern side of the Alps).
So, even a way to replace the 3rd rail system with the threephase catenary would do the trick. Provided, of course, that it be incompatible with the direct current catenary.

I'm requesting this because it would be a vital feature... of course, if one went for sheer accuracy, the FRSet would need *three* different catenary types, with three different voltages, but we're not planning to do that because it would be too much.

eis_os wrote:TTD has actually only 3 bits free

Oh?
All the documentation I've seen (the elect rails code[0] and both sets of landscape array documentation (yours and Marcin's)) say that the track type is stored in a 4-bit field, not a 3-bit field. What took the fourth bit? (and/or What happens when you attempt to set it?)

Not that I think we need sixteen track types, but it seems that if there's a bit there, we ought to at least consider using it, and if there isn't one there, we all need to know about it so we don't try to use it.

[0] See the changes in r824; specifically the removal of several "mov bl, [landscape3+esi*2]; and bl, 0xF; cmp bl, 1; jne .notelectrified" sequences, which could never have worked if something else used one of those bits.

If I remember correctly some code assumes this in the bridge code... (it may be wrong)

Snail wrote:[...] threephase catenary wasn't used so heavily in most countries.

Some more specialities and remarks with regards to electric traction (for the record only, o/c):

- "three-phase" in Italy (3600V, 16 2/3 Hz) used a bipolar catenary. A similar system is used until today by the Swiss Jungfraubahn (1125V, 50Hz) and the Gornergratbahn (725V, 50Hz),

- Italy used other types of electrification as well (numbers are of 1928!):
-- a 862 km three-phase network (s.a.),
-- 4 lines of a total of 364 km three-phase 3300V 16 2/3Hz,
-- 1 line of 172 km three-phase 10kV, 45Hz,
-- 2 lines of a total of 105 km direct current 650V, third rail,
-- 1 line of 101 km direct current 3000V.

- In Switzerland, for the Simplon Tunnel three-phase 3300V 16 2/3Hz had been used, and both the Burgdorf-Thun-Bahn and the Emmentalbahn used three-phase 750V 40Hz,

- the Chemin de fer de la mure used a bipolar catenary for direct current (1200V),

- London Underground and the "M1" line of Milan Transportation System use "Fourth Rail", i.e. two additional "rails" for power supply, in the case of LU one outside the running rails electrified at +420V DC, the other in the middle at -210V, producing an overall traction supply voltage of 630V,

- there were tripolar catenaries for three-phase, namely
-- the military railway (test bed) Marienfelde-Zossen near Berlin (15kV, 50Hz) http://de.wikipedia.org/wiki/Bild:Sieme ... agen01.jpg (this is a must-see!)

-- and the cog-wheel NG engines of "Tagebau Gruhlwerk" (3000V, 50Hz) near Cologne.



Because I don´t know of any other tripolar catenary outside Germany I´d be grateful for any hints regarding that unusual technology.

regards
Michael

Can I ask, how far is work on this project?