Yarn assets and LOD

Paul_Bert

Train Enthusiast
I have found that some of the YARN road assets drop out within 50 to 100 feet. These assets are OK in TANE SP3. In most cases there are "like" YARN replacements that do work as expected.
Was there some sort of adjustment on how LODs are handled in TRS2019. If so they seem to be somewhat severe in how they affect some of these roads.
 
I don’t have TRS19, but are you talking about the splines or about other parts such as intersection pieces? The spline LOD distance parameters are set by the creator via config settings, but the LOD transitions in fixed assets are controlled by the Trainz program and can be severe. This has been a problem in previous versions but creators can learn to cope with it. It’s a bigger problem if TRS19 has suddenly become more severe than before because all the legacy assets will now transition too early.
 
Perhaps this is better dealt with by someone with TRS19, but if you provide the kuid number of one of the splines that has this problem, and it’s a DLS asset, I could look at the config to see if there is anything odd about the LOD.
 
The track-lod tree in all YARN road splines is not optimised what-so-ever. The meshes and track-lod tree would need to be completely re-done to bring them up to current standards.
 
The track-lod tree in all YARN road splines is not optimised what-so-ever. The meshes and track-lod tree would need to be completely re-done to bring them up to current standards.

Looking at some installed examples, I agree, there's no LOD even in the latest (trainz-build 3.5) "YARNish" roads, let alone in the original YARN roads by Maddy25.

However, this does not explain why they "drop out" at a distance of just 50-100 feet in TRS19. Have N3V suddenly implemented some really harsh spline-culling rules? If so it would really make a lot of legacy assets essentially useless in TRS19.


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Looking at some installed examples, I agree, there's no LOD even in the latest (trainz-build 3.5) "YARNish" roads, let alone in the original YARN roads by Maddy25.

However, this does not explain why they "drop out" at a distance of just 50-100 feet in TRS19. Have N3V suddenly implemented some really harsh spline-culling rules? If so it would really make a lot of legacy assets essentially useless in TRS19.


.

Currently I use the JR Road pack which also have no LOD done and don't suffer any drop-out from any distance. I don't think that there has been any changes to the spline culling code.

Example config from one of my old roads on the DLS which are build 2.9 and need updating for TRS2019:

mesh-table
{
lod0
{
mesh "double-line-y-lod0.im"
}

lod1
{
mesh "double-line-y-lod1.im"
}

lod2
{
mesh "double-line-y-lod2.im"
}

lod3
{
mesh "double-line-y-lod3.im"
}
}

track
{
mesh-length 40
adjust-cross-section-to-ground 1

track-lod-tree
{
lod-distance 400

high-detail
{
lod-tessellation-length 10
lod-length 10

high-detail
{
lod-tessellation-length 5
lod-length 5

high-detail
{
subdivisions 8
mesh "lod0"
}

low-detail
{
subdivisions 4
mesh "lod1"
}
}

low-detail
{
lod-tessellation-length 20
lod-length 20

high-detail
{
subdivisions 2
mesh "lod2"
}

low-detail
{
mesh "lod3"
}
}
}

low-detail
{
lod-distance 400

high-detail
{
lod-tessellation-length 10
lod-length 10

high-detail
{
subdivisions 4
mesh "lod1"
}

low-detail
{
lod-tessellation-length 20
lod-length 20

high-detail
{
subdivisions 2
mesh "lod2"
}

low-detail
{
mesh "lod3"
}
}
}

low-detail
{
lod-distance 800

high-detail
{
lod-tessellation-length 20
lod-length 20

high-detail
{
subdivisions 2
mesh "lod2"
}

low-detail
{
mesh "lod3"
}
}

low-detail
{
mesh "lod3"
}
}
}
}
}

With that setup, I get nice smooth curves and even used on PBR Ground textures it hugs the ground in most cases.
 
Harsh/ severe indeed. I have sent in a couple of reports relating to the severity of LODs implementation in TRS2019, especially for certain locos and rolling stock disappearing from view entirely way too early and having highly visible intermediate LOD transitions on their way to oblivion.
QA and the Devs are listening, however, and have showed this with a couple of recent changes made to a couple of the locos I cited as examples.
Now is a really good time to get these road and other splines sorted permanently in terms of LODs, visibility over distance and quality of appearance.
This might involve a combined and concerted effort by original authors, the CRG and N3V developers, aided and abetted by our beta (and public build) experiences and bug reports.
 
Update on the YARN roads dropping out. I went back and imported my route again from TANE. Same issue with several of the YARN assets. I looked at the config file and saw nothing that caught my attention.
So I decided to delete these problem roads and replaced them with the same road (same kuid #). That seems to have fixed the problem. I imported another route with the same YARN roads and the same kuids. Same problem and same fix. Not sure what the issue is with importing these particular kuids, but at least I can fix it easily.

On another similar importing item on one route the Central Portal Control seemed OK with all the commands present as they were in TANE. The only problem is that they did nothing. I ended up deleting and reinstalling the Central Portal Command and re-entered all the instructions and it is now working as expected.

As I continue to import other TANE routes and rework them I will look for other similar issues.

But for now all is well. Thanks for all the suggestions and comments.
 
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