Are LOD still effective with Train 2019 build 110491 ?

vincentrh

Well-known member
Here is a very simple building :


(on the DLS <kuid2:458053:1079:1> SGLM Washing plant 4)

It has two levels of details 0=470 tri and 1=157tri). Its config text provides the tag 'mesh-table-lod-transition-distances' (really long, huh ?) with a unique value of 200.
And untill the current version of Trainz, all levels were displayed correctly.

Today, with the last build, only the first level (lod0) appears on the screen. If we want to make the second level to be displayed, the tag 'mesh-table-....' has to be completed with a second value (for instance : 5000)

Is it normal ?

Vincent
 
It's called new and improved. A bit like the none realistic lighting in TS19 I keep hoping they'll fix one day. I mean if they can get it right in TANE why can't they get it right in TS19?

Cheerio John
 
...

It has two levels of details 0=470 tri and 1=157tri). Its config text provides the tag 'mesh-table-lod-transition-distances' (really long, huh ?) with a unique value of 200.
And untill the current version of Trainz, all levels were displayed correctly.

Today, with the last build, only the first level (lod0) appears on the screen. If we want to make the second level to be displayed, the tag 'mesh-table-....' has to be completed with a second value (for instance : 5000)

Is it normal ?

Vincent

It is normal, or as described here, http://online.ts2009.com/mediaWiki/index.php/Advanced_LOD_Techniques. But maybe N3V tweaked it. I vaguely remember it not working as I expected so maybe something got fixed.

Given you have two LOD meshes you need two values: the first is when the second LOD kicks in and the last is when the model is no longer rendered. In your example 200 and 5000 is a reasonable set of numbers.
 
Thank you Paul for your answer.

However, we can read on the wiki :
The "mesh-table-lod-transition-distances" tag (float array) determines the distances in meters at which each mesh-table LOD level ends. This means that there is effectively one more mesh-table LOD than entries in this array. With an empty array (i.e. to tag value), no mesh-table LOD is used. With three values in the array, four mesh-table LOD indices are used (ie. 0, 1, 2, 3). http://online.ts2009.com/mediaWiki/index.php/KIND_Mesh#mesh-table-lod-transition-distances

Today, should I want my content in 4.6 compatible with the latest version of Trainz, I have to add a new value to the tag 'mesh-table-...", in contradiction with the official recommandations.
So, the question is : wont my contents so modified become again incompatible with a futur release of Trainz ?

I will send a bug report...

Vincent
 
That WiKi article doesn't match with my tests although I admit I haven't tried the combination of an LM.TXT as one of the LOD levels between transition distances.

I made a simple test with a sphere with 4 LOD levels which is TB4.6 compliant. i.e. no errors, no warnings and works in TS19 SP2. It has four LOD transition distances:

20 metres - change from LOD0 to LOD1
40 metres - change from LOD1 to LOD2
60 metres - change from LOD2 to LOD3 which is the very low poly LOD level.
1000 metres where the asset is no longer rendered.

Here is a dropbox link to the asset. https://www.dropbox.com/s/6ild6lmivhgnhrn/PC - LOD test with coloured sphere.cdp?dl=0

I'll remove it in a few days or after you have looked at it if you are interested.

HTH :)
 
And that is exactly how I've been using it, last value is the distance that is no longer rendered so doesn't need a mesh.

It's a thousand time better than the previous fixed lod distance as you have precise control over the distances each one changes at. You can even use it on low poly items to effectively cull them if you can't see it at whatever distance.
 
What you are meaning is pure logic.
But for my part I'm not wrong when I notice that the rules changed since the latest version of Trainz.
Therefore, the question I asked with the bug report I've just sent is : has the rules of LOD changed ? And do I have to review all my objects in version 4.6 ? And is the assertion in the wilki definitively wrong : 'This means that there is effectively one more mesh-table LOD than entries in this array [the mesh-table-....]' ?

Vincent
 
You can still use the old method, the new method came in when TRS19 was first released. Some long time ago, think it was Chris (windwalkr) and pre TRS19, stated that they would make lod easier to manage or words to that effect.
"mesh-table-lod-transition-distances" became a config requirement in TRS19 quite a few builds ago, if using the old method or there is no lod required just add the tag and leave the value blank. I actually put in a suitable distance that the asset isn't rendered at even for under 500 triangle assets.

From a later updated page 2018 in the Wiki

[h=2]mesh-table-lod-transition-distances[/h] The "mesh-table-lod-transition-distances" tag (float array) determines the distances in meters at which each mesh-table LOD level ends. This means that there is effectively one more mesh-table LOD than entries in this array. With an empty array (i.e. to tag value), no mesh-table LOD is used. With three values in the array, four mesh-table LOD indices are used (ie. 0, 1, 2, 3). For small objects, it may be appropriate to not provide any meshes for the final mesh-table LOD index, effectively giving some number of meaningful LOD variants and a final "null" LOD where no rendering occurs.
This is used in conjunction with the "lod-level" tag in the "mesh-table" Container. Note that mesh-table LOD is an entirely separate concept from LM.txt file format LOD. You should not attempt to configure the LM.txt transition distances using this tag. It is, however, possible to combine the effects.
This tag does not override user settings for draw distance and scenery detail. If a LOD transition takes place beyond the master draw distance for that object type, it will never be visible. Furthermore, at lower detail settings the LOD ranges may be adjusted to be more aggressive than specified by the content creator.
 
I wonder if this has anything to do with the assets which suddenly mysteriously disappeared after a certain distance in my 'Much Murkle' route in TRS19 (compared to TS12 and TANE) until I entered a second set of distances in the config? If so, potentially quite a lot of assets using 'old fashioned' LOD could be affected in TRS19 and no longer function properly.

Paul
 
The 'bug' I report concerns only objects that use the tag "mesh-table-...". Therefore, only 4.6 and 4.7 assets are impacted.
As your route + session doesn't contains any asset of these versions of Trainz, the source of your problem is to seek elsewhere.

Vincent
 
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