How do you setup reflections of particles?

A while back I noticed that particles were not showing up on my reflections. Recently, I’ve been doing a lot of tests with them. and decided to try it again, but they don’t seem to be working.

Whats the proper way to setup a reflective surface to also capture particles?

I conitnued my search and the only thing I’ve found mentioning particle reflections is here: https://answers.unrealengine.com/questions/15934/material-metallic-reflection-bug.html

I decided to try turning on AA since it was mentioned. I made a post process volume, set it unbound and turned on temporal… it … works… but the reflection upside down.
:frowning:

the reflections do not show up with FXAA or NONE options.
I think ya got a bug here.

Hey xdbxdbx -

The only way dynamic objects such as particles will show up in reflections is when using the Screen Space Reflections through a Post Process or Camera setting. I would recommend adding a Unbound Post Process volume to your level and in the details check ScreenSpaceReflections >> Intensity to above 50 % and >> Quality to 100 % (these settings can be adjusted as desired, just a good starting point). Within the Screen Space Reflections reange you should now see your particles reflected.

There are some cavets that I would like to point out with reflections that will come into play here. For Translucent Materials used in a Particle make sure that responsive AA is checked true. The AA settings can be adjusted but I find changing it from Temporal AA does not help the blurring of reflections on a flat surface which is in fact a known limitation of reflections in the engine currently, Engine Feature Examples for Unreal Engine | Unreal Engine 5.3 Documentation :

It is extremely important to setup your scene’s materials to work well with the Reflection Environment. A flat, mirror surface will reveal the inaccuracies of combining cubemaps projected onto simple shapes. However, curvy geometry or rough surfaces can both obscure these artifacts and provide convincing results. So it is important to use detail normal maps and specify some degree of roughness on materials that will be used in flat areas.

Particles systems that already have a nature blur to them (like clouds, smoke, etc.) tend to look better in a true flat reflection surface while opaque or mesh related particles tend to be more blurry.

I will leave you with these two examples of a soft particle system and an opaque particle system on a flat mirrored surface and a surface with roughness (ie a Normal map applied)

If you have further questions please feel free to ask -

Thank You

Eric Ketchum

I just had the darnedest time getting this to work. Helpful note, particle reflections only work with Temporal AA. Hope this helps someone!

Hey. thanks for this explanation.

I wanted to check though, is it possible to have particle reflections with using Planar Reflections?

Thanks!