Ongoing Investigation: SP6 Route Performance & Redraw Issues

[n3vpolsen]

Hi everyone,

We want to provide an update regarding the reports players have made about performance and redraw behaviour since the release of TRS22 SP6.

What We Know​

• Some users are reporting that routes which worked fine in SP5 now show stuttering, unloading/reloading of scenery, or redraw loops in SP6.
  
  
• Especially around major stations or when multiple locomotives/rolling stock are present.
  
  
• In at least one test case, replacing a small number of very heavy spline assets resolved the problem. For example, one track asset was found to be 1.5 million polygons with hundreds of draw calls, when tested in ‘performance analysis’ mode in the Preview Asset tool, which is far beyond practical limits. To give a comparison Kickstarter County II uses a track asset with 130,000 polygons.
  
  
• Our internal testing has confirmed that a recently introduced memory management system is being triggered more often than we expected in certain routes. This system was introduced to reduce crashes caused by excessive memory consumption. We expect that this is likely the cause of much or all of the reloading/redrawing of scenery, especially splines.
  
  
• We are investigating whether the limiter itself is behaving as intended, or if specific assets or scenarios are pushing it harder than expected.

What We Don’t Yet Know​

• Why these issues were not reproduced during internal QA or external beta testing.
  
  
• The extent to which this is caused by individual high-poly assets versus a broader systemic issue.
  
  
• Whether the 'redrawing' affects performance negatively; it's a reasonable assumption that these might be linked but we don't have any strong evidence of that at this stage.
  

What We’re Doing​

• We’re actively reproducing reported cases using both internal and community content.
  
  
• We are reviewing routes reported so far, and comparing SP5 vs SP6 behaviour.
  
  
• We are gathering more data to determine if the issue lies with the limiter thresholds, specific content, or a combination of both.
  
  
• We are reviewing options for improving outcomes via code changes, but we also recognise that some content may need optimisation going forward.

How You Can Help​

To move forward, we need concrete examples we can test directly. If you are seeing this issue, please:

• Provide the exact route/session name and KUID if from the DLS/DLC Pack, or package your content up and send it to us (Google Drive or other download is fine).
  
  
• Indicate in detail where on the route/session the problem occurs. Surveyor coordinates or the exact name of a nearby named object would be most useful.
  
  
• Include details such as draw distance settings, framerate at the time, and other graphics settings.
  
  
• If you can, take a screenshot or video showing the problem.
  
  
• Submit a helpdesk ticket with your details, so we can track and compare reports more effectively.
  
  
• If you're significantly affected by this problem, and you use the Windows Trainz Store version of the product, and are willing to help test beta fixes, let us know.
  

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We know it’s frustrating when content appears to break after an update. Please be assured this is not being ignored—we’re actively investigating and will continue to share updates as we learn more.

Thanks,
The Trainz Team

 

[HPL]

• Some users are reporting that routes which worked fine in SP5 now show stuttering, unloading/reloading of scenery, or redraw loops in SP6.
  
  
• Especially around major stations or when multiple locomotives/rolling stock are present.

A route creator stated here that stuttering is anywhere on his route.

 

[cabnz1]

The scenery problems are happening on multiple routes and anywhere on them. I'm definitely not wasting my time going over the process above as this is on N3V who has done something majorly wrong.

I'm using two main builds which are working fine for me. They are Builds 126280 and 129343.

Build 131950 is a complete mess!

 

[RBrooks]

Thanks for the acknowledgement of the performance problem, @n3vpolsen. I'm pretty certain I can help with this.

First, I'm posting my 2 examples of the problem, just in case you did not see it in the other thread:

Spoiler: click here

Second, I can try sending you some community routes with scenarios (of course with authors permission) which reproduce the issue. Is there a direct e-mail?

 

[BBarnes005]

The only routes I have experienced this on so far are Hawaii Railway from CPS and Gila Railway from NARM. The former upsets me the most because I used it quite a bit for screenshots and it was perfectly okay prior to SP6. Gila did have draw issues during SP5+HF1, but that could be resolve by deleting a handful of assets, this however would not go away regardless of how many assets I replaced/deleted.

I've already submitted a bug report to the Support Desk, which is what I created the video for.

 

[mikeman]

Here is one thing you can do to help. List said Rail asset and other problem assets. That way we know what to look for first.

 

[Sanek17]

From this we can conclude - we have nothing to do with it, it is you who put everything in the game... Although in SP5 everything worked fine, but now it just lags and takes a very long time to load on powerful computers. Couldn't you just add trees without messing with the scripts?

 

[pdkoester]

@n3vpolsen
What are the specs for the internal QA systems being used?

 

[JCitron]

The only routes I have experienced this on so far are Hawaii Railway from CPS and Gila Railway from NARM. The former upsets me the most because I used it quite a bit for screenshots and it was perfectly okay prior to SP6. Gila did have draw issues during SP5+HF1, but that could be resolve by deleting a handful of assets, this however would not go away regardless of how many assets I replaced/deleted.

I've already submitted a bug report to the Support Desk, which is what I created the video for.

Gila doesn't have a whole lot of assets to begin with and the sagebrush assets are being repaired by the content creator.

 

[Beko]

Provide the exact route/session name and KUID if from the DLS/DLC Pack, or package your content up and send it to us (Google Drive or other download is fine).

I've tried various routes, including payware (free) "Canadian Rocky Mountain, Sebino Lake..."It works on all of them.Now I've downloaded my own route, "Margining Yard Maschen," ( Rangierbahnhof Maschen) from DLS kuid: 2:132608:100685:1 Just try out the route, as I said it's on the DLS.
Up to build: 129876 the track (and others) runs perfectly
in build 131950 and see this:

Here's the comparison in build: 129876 Every update after that causes errors like Screen 1

Greetings Beko

 

[norfolksouthern37]

I Have another one that I don't see showing up anywhere else. I have assets with cab computers in the cabs. These have a clock that displays the current world time using the script call World.GetGameTime(); to gather and display the clock numbers. Since installing the update to 131950 the world clock is not running when the session starts. It does not start unless you go to the time settings and choose a time rate, then it will begin "ticking".

In addition, the call World.GetGameDate(); returns the wrong day (one day ahead of game calendar) as it did in the last build and was reported. This same call previously returned the correct day several builds back.

 

[Sanek17]

Why bother with something that was already working? They just introduced new trees and that's enough. Make a new sky and lighting! No, we'll continue to break everything and then heroically fix it! I'm tired of it, every patch is the same thing