Why No Ambient Occlusion In The Passenger Interiors?

As the title states, I've always noticed a lack of AO in the passenger interiors. This makes the interior look very flat, and in most cases look far too bright.

For those of you that don't know what this is, its something which adds shadows and dark spots the areas where the light source doesn't reach, such as under tables and seats, for example.

I understand that it may cause some sort of performance issues, but surely there could be some AO included?

Below is a screenshots of it both enabled and disabled. Notice the vast differences.

TS1 on:


TSW off:

 

That is a big difference. Hopefully dtg can add some sort of AO in the future. Alot of the trains in this game has passenger interiors that look too bright. The M3, Class 395, 375, 377 are some examples. Would it be a big performance hit though?

 

Agreed always bugged me as well.
Seems Rivet may have addressed this in there preview vid.

 

Would be nice to have the trains feel like trains and not hospital corridors, but I don’t see this change happening any time soon.

 

I noticed Rivet had managed to add it as soon as I watched the video. Everything looks a lot more realistic like. The performance looks great too.

DTG should really think about adding it in, or at least provide some sort of option to enable/disable it.

 

Would it be as simple to have an option to enable or disable ambient occlusion though for all trains in tsw2? I can already hear someone at dtg saying "for technical reasons, this isn't possible or "This would be a massive undertaking"

 

“Baking” to maybe go onto the bingo cards anyone?

That’s getting to be quite the buzzword for DTG lately.

Theoretically it should be quite simple, depending on how Unreal Engine handles the implementation of AO, although DTG clearly take the complicated route with some of their development practices, for one reason or another, which sooner or later proves to be a rod for their back.

 

Baking AO is by far the best option, because it takes 0 performance hit at all (it's just a part of the texture). Using real-time AO through post-processing would eat up GPU resources unnecessarily.

I have always wondered why DTG do not bake in AO for the passenger interiors, despite doing it for the cab. I suppose the simple answer is that it requires vehicle artist time which they seem to be short on.

Cheers

 

AO in TSW is always baked into a separate Texture-Map. It is not baked onto the BC. That would be a bad idea. In TS1 it is often baked into the BC and therefor does not react to any light sources. In TSW the AO is reacting to lights. And that is the reason for the 'absence" of it visually often. The light sources in UE4 are 'burning' away the AO. We have experienced this with the G6 while making the texturing. As son as you have a brighter light switched on, like cab lights or the flashlight, the AO disappears magically. Have found no way around yet.

 

Ohh i see. Thanks for the answer. Hopefully a solution can be found but it doesn't look like it's an easy task. It's weird entering some trains in the game that have lighting that is way too bright.

(P.S. I'm looking forward to the DB BR 420 )

 

Maik Goltz I’m not at all technical minded enough to know how everything works, but how did Rivet get their interior to look so good?

 

They may have used a stronger AO at all. We did that too, it was horrible when you have no lights on. It is then black as hell. OR they baked it into the BC, i don't know. It is easy to get the idea when it is out. Get into the thingy, lights off, if its black like "you know where", and you can burn it away with the flashlight switched on, then it is strong AO in a separate map. If it is not burning away with the flashlight, its baked into the base colour map. You can do that, but this can have side effects with the overall lightning then. Could be generally too dark then in every light situation.

 

Personally, I’d rather it be too dark than too bright. Most of the time train interiors are just way too bright and clinical looking.

The cabs are better, but I still think it needs more AO/needs to be darker in places. There’s an SSGI ini command I sometimes use which helps with this.

 

SSGI does nothing for AO at least. SSGI is additional indirect light to the scene that lightens up the scene where already baked light is applied with the Lightmass baker. It does nothing so far for the trains in TSW other than maybe make them even brighter.

 

I found it makes shadows/lack of shadows appear under bridges/makes them deeper looking, as well as it makes areas of the cab darker/adds additional shadows.

For example it’ll make the area around the throttle and fan darker whereas normally it’d all be the same lightness.

 

But then you dial it down instead of up, right? It may be to much with the default settings and when you then dial it down, it reduces the overall additional indirect lighting, what then causes AO to be more present. But honestly, that is not what it is supposed to be. "Someone" needs to learn how to use it

 

How does one dial SSGI up / down independently? Based on the UE4 commands I've seen, SSGI is either enabled or disabled.

Or did you mean dial the overall lighting up / down, which then influences how SSGI is rendered?

I agree londonmidland - enabling SSGI has made shadows / overall lighting far better than vanilla, especially in the cab

 

The only commands there are is to either enable or disable it, as well as set the quality of it. You can’t actually set the intensity of it via commands as far as I’m aware.

 

Notice the differences under the bridges. By default there’s no shadows or darkening where there should be.

Default SSGI disabled:


SSGI enabled:

 

That is weird. This is not the effect it should have. Read the docs from Epic about that feature and what it is supposed to do. Seems more it is not quite compatible with TSW lighting solution at all.

 

Try it yourself if you want a bit of fun inside TSW. You’ll notice once enabled, it’ll make areas go darker/add shadows to it. Most noticeable is inside cabs, it’ll reduce that weird blue tinge TSW gives off.

I think we can all agree TSW’s TOD system isn’t exactly the best

 

Ah, then i know what it really does for TSW, it switches off the sky light. That is quite bright in TSW and has this blue tint when you have no clouds on the sky. I think the effect you see with enabling SSGI is not having GI enabled, but having skylight disabled the same time. There is a command to disable the sky light or dial the intensity down. It should have the same effect then if i'm right

 

I believe it’s skylight intensity or something like that? That’ll make areas out of indirect sunlight/light sources darker. I have mine set at 0.5.

You can also change the Ambient Occlusion Method. The default is SSAO but you can set it to GTAO, which reduces light source intensity. This makes everything look too dark out of direct sunlight, however.

 

r.SkylightIntensityMultiplier

Lowering this value from 1 affects all lighting. Effecively making the daylight darker, but not in a natural way - like wearing sunglasses. Tried it at 0.5 but it looks way too dark, though appreciate this will be subjective.

 

Unfortunately there doesn’t seem to be any other effective way of increasing the depth of shadows, without making everything else too dark. I find by default everything is way too ‘flat’ looking, as TSW’s skylight causes some weird side effects with the lighting.

 

That looks like a pretty good result. Which line is this SSGI exactly? I'm thinking about trying it out myself.

 

I use it via Unreal Engine Unlocker, but I think you add it to your engine.ini file to enable it permanently.

I recommend using:
r.SSGI.Enable=1
r.SSGI.HalfRes=1
r.SSGI.Quality=3

 

Could an invisible rectangular mesh (kind of like a collision box) placed in the seats' position work as a "placeholder" for the AO?

I mean I'm kind of thinking like in many old games, where they had the actual 3D model for display, but had a different low-poly model used just for rendering shadows on the ground. Just a thought, don't know if it even makes sense in this regard.

Thank you, I will try it out next time I play.

 

Not even needed i would say. You need to render a AO map with the seats in place and thats it. But again, AO gets burned away from light sources. So this is a different problem on top.

To show what i mean with "buring away", a actual example from my loco where we rendered the AO accidentally underneath a switch. The flashlight burns it away completely. And so do other brighter light sources.

 

Just increase r.Color.Mid and r.Color.Max at the same time when decreasing r.SkylightIntensityMultiplier.

 

Try this (keeping you SSGI settings enabled):

r.Color.Max=1.0
r.Color.Mid=0.5
r.Color.Min=-0.01 (note the minus. This is <0)

Maintains the brightness / vibrancy of the sun, but deepens all shadows. You can go even deeper by reducing color.min in small increments below 0, or higher if the shadows are took dark. E.g. r.Color.Min=-0.007

 

Thanks, I’ll give it a try later.

 

I use GTAO (Ground Truth Ambient Occlusion), I think it produces a better result than SSAO and it doesn't use more resources unless you go wild with the values, also you get ambient occlusion in passenger interiors and darker shadows.

I use these values in my Engine.ini

r.AmbientOcclusion.Method=1
r.GTAO.FalloffEnd=35
r.GTAO.SpatialFilter=0
r.GTAO.NumAngles=2
r.GTAO.UseNormals=1
r.GTAO.ThicknessBlend=0

 

I’ll give this a try later. Would you mind posting some in game pictures of it, please?

 

GTAO (Ground Truth Ambient Occlusion)
Exterior On

Exterior Off

Interior On

Interior Off

 

So, which works better?
a) SSGI
b) GTAO
c) Both of the above

 

I've tried them out and I have to say, it's a pretty good result. It's subtle, but definitely gives more detail to darker areas and gives everything that nice little touch. I especially liked the results in the underground sections of LIRR.


But sadly, my GTX 1050Ti didn't really like it, I had quite a significantly lower framerate with these settings. So I think I'll have to go on without them.

 

Having tested the three variants above, I recommend GTAO. SSGI can look great, but it's not worth the additional performance hit.

You don't need both.

I currently have GTAO set at 300, but well worth experimenting with different values.

My settings:

[SystemSettings]
r.TextureStreaming=0
r.Streaming.HLODStrategy=2
r.Color.Max=1.0
r.Color.Mid=0.5
r.Color.Min=-0.002
r.ViewDistanceScale=4
foliage.LODDistanceScale=3
r.Shadow.FilterMethod=1
r.Shadow.DistanceScale=2
r.LandscapeLODDistributionScale=3
r.EyeAdaptationQuality=2
r.MaxAnisotropy=16
r.BloomQuality=5
ts2.CameraMotionSway.EnableUprightCompensation=0
ts2.CameraMotionSway.KSitting.Y=200.0
ts2.CameraMotionSway.KSitting.Z=200.0
ts2.CameraMotionSway.LSitting.Y=40
ts2.CameraMotionSway.LSitting.Z=5.0
ts2.CameraMotionSway.SittingPivotOffset=-200
ts2.CameraMotionSway.LSitting.X=50
r.DefaultFeature.LensFlare=True
r.LensFlareQuality=2
ts2.passenger.DensityScale=2
ts2.platform.MaxPlatformPassengerSpawnDistance=300000
ts2.platform.MaxStationPassengerSpawnDistance=400000
ts2.platform.MaxSpawnInterval=5
ts2.platform.MinSpawnInterval=150
r.SkylightIntensityMultiplier=1
r.LightMaxDrawDistanceScale=150
ts2.dbg.Camera.MaxVerticalHeight=5000
ts2.dbg.RelinquishPromptWaitTime=60
r.AmbientOcclusion.Method=1
r.GTAO.FalloffEnd=300
r.GTAO.SpatialFilter=0
r.GTAO.NumAngles=2
r.GTAO.UseNormals=1
r.GTAO.ThicknessBlend=0
r.GTAO.Upsample=1
r.GTAO.TemporalFilter=1
r.PostProcessAAQuality=6
r.TemporalAASamples=4
r.TemporalAASSharpness=2
t.MaxFPS=60

[/Script/Engine.UserInterfaceSettings]
ApplicationScale=0.650

[Audio]
UnfocusedVolumeMultiplier=1.000000

 

Which video card do you use these settings with?

 

OK. With my current settings the shadows are inky pitch-black, even with r.color.min set to 0. Going to have to play some more. To lighten GTAO, does one go up or down from 300?

 

An RTX 3080

 

What are your color & sky multiplier settings?

To lighten, go lower. To darken, go higher

 

r.Color.Max=0.8
r.Color.Mid=0.5
r.Color.Min=-0.0
r.TonemapperGamma=2
r.SkylightIntensityMultiplier=0.5

By lower, do you mean 290, or 200? Or 20? Often meaningful increments in these settings are hard to make sense of (with r.color.min it's 1/100ths!)

 

Damn. My 1050Ti is not going to love them then, lol.

 

Before changing your GTAO settings, I encourage you to:

1. Revert your color settings to 1, 0.5 and 0
2. Revert your sky intensity multiplier to 1.

Then use your current GTAO settings and see what you think.

The settings you have are massively decreasing the intensity of light in each and every scene. It's literally like walking around with dark sunglasses on.

However, this is all subjective, and you may prefer your current settings.

GTAO: Drop it by 100 at a time, then fine tune from there. E.g. Try it at 200,100 and 50, and tweak up / down from there.

*Deeper shadows can be further enhanced by lowering color.min below zero. For example, mine is set at -0.002 (note the minus).

Curious to hear your thoughts!

 

The commands with most impact tend to be distance scale, so those can be tuned down. Try them and see. I reckon you'll be good to go!

 

Yes. I put them in to correct the default overbright, washed-out look.

I did have r.color.min set to -.008, which worked well before the GTAO tweak. Moving it back to zero was an attempt to compensate, but the shadows are still way too dark.

 

All good. Keep lowering the GTAO value until you find your preference.

 

I think the problem lies partially in UE4 where you can't pre-bake Global Illumination to imported models without overly complicated material shader models. Good news is that UE5 is going to fix this pretty much. I tested the UE5 and the results with unbaked model are very similar to prebaked textures with the addition that the illumination actually changes dynamically(cabin shadowing and wall reflections look very different based on time of day and surrounding environment)