Hi everybody,
Working on a playable archviz project. Requisites are day/night transitions and outdoor/indoor lighting.
In this context, how can I prevent an indoor translucent object (individually) from being reflected by the SkyLight/ SkyAtmosphere? Sorry if it’s a rookie question, I’ve been with unreal for a few weeks.
I think that if an object has only translucent materials then it will not be reflected. If it has at least one opaque material then the entire object will be reflected as it would be opaque. So making the glass a separate object should stop it from being reflected if the material is translucent.
Thanks for replying S-Dot,
The glass is a separate object, and its only material is translucent, as you can see in the screenshots.
It looks like there was the same problem in previous versions, but I guess it wouldn’t be with lumen.
Have you tried the tickbox for “include translucent objects” in the post process volume under raytraced reflections?
I’ll try it myself later and let you know.
I don’t really use a skylight in unreal 5. Or I set the value to 0.01. it just seems to mess everything up.
I’ve noticed that SkyLight also affects Niagara particle systems (or their translucent materials) with RayTracingTranslucency>Refraction:true… We don’t want to lose this property, as it adds realism to the glass and its reflections outside. (for example, on windows). Can’t specific objects or materials be excluded from this reflection when the sky or the atmosphere doesn’t affect them?
I’ve been doing a few tests. Here is what works ok for me:
The only reason to have the skylight enabled is that framed pictures with a glass sheet in front are totally black without a skylight.
Speaking about the glass material. This may help:
Actually I found out something interesting: I set the reflection back to lumen and increased the quality to 4.0 and enabled “Hit Lighting for Reflections”. And it looks pretty much as good as with ray traced reflections. (except the mirror maybe).
So what really makes the reflection on glass get bad is setting translucency to raster. If translucency is set to ray tracing then the reflections on glass look pretty good.
I also increased the intensity of the skylight. 0.1 seems good.
Thanks for introducing me to this guy, his videos are really interesting. I agree with your comment about mirrors.
We don’t want to do without the SkyLight element, we need that blue sky outside with day/night animations, but it is true that it works better in the values you mention.
From what I see, Unreal’s problem with glass is that for each case you need a particular configuration, while this configuration depends on the PostProcessVolume, which works globally.
You can make the window look perfect, but if you have a glass of wine next to it, it is very difficult for both to be realistic at the same time.
This is the most acceptable result we’ve come to, but at the sacrifice of the RayTracingTranslucency:Refraction property. In addition, the reflection of the material depends on its opacity, so it is difficult to obtain sharp reflections while keeping the object translucent. (the mirror by RayTracing is still a drama)
check the box " Affect Ray Tracing Reflection " on skylight . It might helps
