2019 ignoring especs?

flyboy559

Using Trainz since 2003
Build version:105100
I have several locomotives where the game seems to be ignoring the e-spec files and deciding on its own how the locomotive should be acting such as top speed overall and the ability to climb hills or negotiate curves. One example of this is trainboi1's WVRR 4-8-4s. According to the e-spec it should be capable of 29 meters per second, but in game on flat ground without any tonnage behind it the game tops the speed at less than half that. I checked with trainboi1 and my e-spec file is correct, the game just doesn't want to accept the speed apparently.
 
hi Will,


Its worse than you think, broken for almost 2 decades
engine specs have never worked as originally designed (in 2001?)


in 2004 i worked a lot with german specialist Brummel, he helped me with the engine specs
returning in 2019 I find its not better, but worse than before...


there are over 84 parameters, yet only a few actually work
under AI and DCC, these actually do something:
maxspeed
brakeratio
max-accel
max-decel
but they never stand alone, also the (combined)mass of your train has influence.


I had several cases, where setting maxspeed lower (29) to make trains actually listen to the speed required.
so first experiment with the maxspeed setting, till its correct under dcc/ai.


in cabmode, the throttle-power and dynamic-brake containers do have influence,
and a few more parameters work but (guessing) not even half of them.


if Trainz wants to be a realistic trainsim, there is a lot of work to be done.
for now, its a lot of trial and error, with no idea what actually works.
maybe that new TNI will be a chance, for an external specialist to improve it.
greetings GM
 
Hi Will --

Steam locomotive especs. Hmmm. The short answer is that they are a black art known only to the initiated few, who meet in secret when Venus is in ascension and The Ides of March have passed. They chant ancient incantations and make offerings of dead animals in the middle of a moonless night. Unfortunately, or perhaps fortunately, I'm not a member.

So I did try the rational way -- collecting all the real life data, trying to make sense of the Wiki, ... . The result was abysmal.

Out of desperation I decided to take one of the especs that seemed amongst the better and made modification so that it would perform in a way I thought was "satisfactory", where satisfactory is:
Hauling a realistic load at a realistic speed on the flat while maintaining or gradually increasing boiler pressure.
Loosing boiler pressure when being flogged uphill.
Gaining boiler pressure downhill.

This assumes the correct driving technique:
Full open regulator.
Control speed with the cut off.
Maintain water level.
Add coal little and often.

All this meant fiddling with some of the parameters and trying to work out how they affected speed, power and boiler pressure. It's so long ago I can't remember the exact details.

Anyway, the result was the two especs of mine on the Download Station. One is for smaller locomotives, the other for big steam power. They certainly aint perfect but they do work reasonably well in practice. Well, at least until about T:ANE, when something must have changed inside the simulation. Now the safety valves pop far too frequently. If this sound irritates you has much as me it can be overcome by editing the built-in Sound file.

Good luck,
Phil
 
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Hi Flyboy559
The first important question is to ask if you are driving in Realistic Mode or Simple Controls Mode.


Values in the 'motor' container will set the Simple Controls 'physics', including the top speed. These only apply under Simple Controls and under AI control, but how quickly you reach the top speed will still vary depending on train weight and gradient. The exact top speed can sometimes vary a little as well, but should be very close. This value has no direct bearing on Realistic mode.

However in Realistic Mode, the values specified in the 'steam' container are combined to make the top speed. This can be very different to the maximum speed specified in the enginespec asset, as the top speed is based upon a lot of factors both in the enginespec and how you are driving the train, as well as the gradients/etc.



Its worse than you think, broken for almost 2 decadesengine specs have never worked as originally designed (in 2001?)




in 2004 i worked a lot with german specialist Brummel, he helped me with the engine specs
returning in 2019 I find its not better, but worse than before...




there are over 84 parameters, yet only a few actually work
We rebuilt the steam physics system in Trainz Classics 3. Those made for Trainz Classics 2 and earlier will not run the same as they did previously. The only options here were to either completely stop those locos running entirely, or maintain a basic compatibility mode that allows them to run, but not necessarily as perfectly as they may have previously run.

From my personal experience, having built a lot of different steam locomotives in my spare time, the parameters in the 'steam' container do make a difference to performance of steam locos.


in cabmode, the throttle-power and dynamic-brake containers do have influence,

and a few more parameters work but (guessing) not even half of them.

Steam locomotives use neither the throttle-power or dynamic-brake, these are for diesel locomotives only. However due to the way that Trainz reads enginespecs, it still requires these containers to be present.

if Trainz wants to be a realistic trainsim, there is a lot of work to be done.
for now, its a lot of trial and error, with no idea what actually works.
maybe that new TNI will be a chance, for an external specialist to improve it.
greetings GM

There is definitely always work to be done, and that is part of why we have implemented the TNI system so that creators/programmers can have the freedom to design their own engine physics systems to expand upon this.

The short answer is that they are a black art known only to the initiated few, who meet in secret when Venus is in ascension and The Ides of March have passed. They chant ancient incantations and make offerings of dead animals in the middle of a moonless night. Unfortunately, or perhaps fortunately, I'm not a member.

I know we've covered this before. However this is a very unfair description of the enginespec system. Steam locos are inherently VERY complex machines (this comes from hands on experience with steam as well, albeit most recently with stationary steam engines), and this does mean that making them work realistically in a game requires quite a lot of work.

This also means that creating an enginespec requires a lot of testing, and tweaking, of the enginespec. This is time consuming, but so is making a steam locomotive in general. The alternative is to find a suitable similar enginespec to use on the locomotive.

As noted earlier, a very good start point for creating an enginespec is this guide: http://online.ts2009.com/mediaWiki/index.php/HowTo/Tune_a_Steam_Locomotive_Enginespec

This is what most of us use as a start point. It outlines which values are intended to be adjusted, and which ones should be set based upon the real world values (ie would be 'fixed' values). This can take a lot of testing, and a bit of experimenting.

One thing that needs to be noted, is that currently we don't have support for dampers. This does mean that for the most part you need to make the boiler lose heat a bit quicker than you otherwise might want, and then use the blower to counteract this to some degree. However this isn't far off prototype, where generally the blower will be open to some degree most of the time (this can help even out the draft on the fire, and help keep the fire hot if you are having to alternate between coasting and powering).

Regards
 
I love Phils description ;-) (sorry)


Zec we all love Trainz very much, you know that by now,
but enginespecs in a Trainsim should work as expected, not be unneeded confusing to Users or Content creators.
TNI will help maybe, but the basegame should be good after 20 years.


You kinda confess, to all of us that we used our precious time study and fine-tune, for nothing?
it feels like writing very precise camber settings for a F1 car, then put square wheels on.


I made about 20 enginespecs, for my Diesel/Electric trains and even busses and trams.
Am lucky to have among my friends 2 guys that actually drive steam trains and 3 that drive Diesel/Electric professionally
(You may consider it a compliment they play Trainz in their free-time)
Their feedback, helps me a lot.
I know the wiki is written by users, but make sure we know atleast which parameters actually work and which don't.
greetings GM
 
Hi Flyboy559
The first important question is to ask if you are driving in Realistic Mode or Simple Controls Mode.


Values in the 'motor' container will set the Simple Controls 'physics', including the top speed. These only apply under Simple Controls and under AI control, but how quickly you reach the top speed will still vary depending on train weight and gradient. The exact top speed can sometimes vary a little as well, but should be very close. This value has no direct bearing on Realistic mode.

However in Realistic Mode, the values specified in the 'steam' container are combined to make the top speed. This can be very different to the maximum speed specified in the enginespec asset, as the top speed is based upon a lot of factors both in the enginespec and how you are driving the train, as well as the gradients/etc.

Regards

Hi Zec, thank you for your response to my question. I am running in DCC (Simple) mode. Per trainboi1 " The maximum speed in DCC mode is 29 m/s, or about 65 mph. In Cab mode I typically find it capable of easily holding 60 across a flat with 700 tons, or maybe 25 up a 4.5% grade with the same load." yet I am getting only half that with no weight behind the locomotive on flat tracks.
 
Hi Flyboy559
I have tested this here in a couple of builds and it does appear that the current TRS19 SP2 build is not handling the max speed tag correctly. However the good news is that this does appear to be resolved in the next update. We would welcome anyone who is interested in testing the updated physics systems in the next update to install the TRS19 Beta, which you can find information for here: https://forums.auran.com/trainz/sho...-111341-(PC)-11347-(Steam-PC)-and-111343-(Mac)

Regards
 
Zec, I tested a different steam loco, I don't have the payware one called out in the OP. I used Ben Neal's old USRA 2-8-2A that was updated to a 3.5 config and repainted to PRR L2s. I create my own especs for all the steam locos I own - if I can edit the configs.

I don't have TRS19 SP2 installed right now but I've got TRS19 (v100240) and SP3 beta (v111341). I ran the test on my steam loco test track, a flat oval main about 10 km straight and level on each side. I set the maxspeed tag to 29 (64.87 mph) in the espec and in both versions it topped out at 65 mph in DCC under user control as shown in the display. I then put 4400 tonnes behind the tender and got the same results. (See below for what I got in cab mode with this load.)

In game pic of the L2s doing 65 mph top speed in DCC mode on my own Steam Loco Test Track.
Test-DCC-Espec-PRR-L2-at-64.9-mph.jpg



In cab mode I topped out at 25 mph with the 4400 tonnes. Several mph less than I had expected but the last few mph take forever when you're running at max output and the acceleration is next to nothing. I haven't run any tests of the steam physics in TRS19 so maybe it's time.

I dl'd a set of freeware WVRR 2-8-2 loco's from Trainz Forge last night and I might get a chance to install them and look at the loco configs and especs later today.

Bob Pearson
 
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Zec I noticed 1 thing with the WVRR 2-8-2 locos I dl'd. The tenders are set up as a powered loco in dcc mode. The tender and loco have different maxspeed tags and others in the motor container in their respective especs. I always wondered how Trainz considers multiple locos in the train that have different maxspeed, max-accel and max-decel tag values under DCC mode but was never interested enough to do any actual tests.

I modified the espec for the loco same as in the above post and it maxed out at 65 mph in TRS TRS19 (v100240). I may try SP3 beta tonight but the locos had some problems installing. Problems with the loco script I think. A loco script library got over written - probably by user error on my part. I tried to revert it but an EDBR finally fixed all the faults. I have yet to load them into SP3 beta.

Bob Pearson

[EDIT] PS. Installed the locos into SP3 beta (v111341) and got the same results as above on my test track. All locos I tested reached a top speed of 65 mph in DCC mode with the maxspeed tag set to 29 in the espec.
 
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