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No Reflection on Translucent Materials

Hey everyone. I am new to using forums, so bear with me if there is any confusion!
I actually have a question regarding the reflection issue with translucent materials. I know adding a reflection is done by using refraction, however, when I add a good value for refraction that gives the effect I want, the material splits when I look at a certain angle. I am creating an ocean shader if that helps at all.

Refraction isn’t used for reflections as such. For reflections in translucent materials you still have to use Roughness and Specular inputs. The thing is (if this wasn’t changed in 4.4 which afaik wasn’t) that SSR doesn’t yet work with translucent materials and you are getting only reflection from one reflection sphere.

That’s not how it’s done actually, reflections are handled natively by the engine depending on Roughness, Specular and Metallic values. However there is a caveat, translucent materials do not currently work with the real-time reflection system in UE4. Instead you have to use render-to-texture targets and reflection capture actors, and manually add them to your material. In some cases you many even want to use blueprint to drive it.

Refraction distorts pixels BEHIND the surface, it simulates light being distorted as it travels through a medium. The splitting effect your seeing is determined by the ‘Refraction Depth Bias’ value in the material properties. You can adjust it, but it will have adverse effects in other areas.

Actually, you can get some reflection from reflection capture actors automatically. You have to use TLM Surface in the Translucency Lighting Mode. This should give you reflection from the closest capture actor.

True although it’s not great, water is just plain hard to pull off at the moment.

Thanks y’all!

Does anyone know where there is a tutorial on how to set this up it has been killing me trying to get this working.

I’ve been trying to get this to work, but only managed to do it in UE 4.6. Is this a feature of 4.6, or is the system just buggy and it fails to detect the reflection captures almost always? See my thread here: https://forums.unrealengine.com/showthread.php?55084-Translucency-and-Reflections-finally-working-in-UE4-6-but-still-so-many-problems&p=197063#post197063