How to create a dynamic/realtime reflection?

In my scene I’m currently using the BP_Sky_Sphere example content with a transition from day to night.
In the “middle” of this scene i have created a reflective window with a SphereReflectionCapture.
This window captures the surrounding environment perfectly.

When the surrounding environment changes color/light dynamically, the reflection does not(obviously it simply captures the scene at launch).
I can’t seem to find any documentation on how to achieve a dynamic reflection.
Any suggestions?

Hello Joki,

So in order to do update your scene reflections when using a dynamic light the moves from day to night as you described you will need to do some Blueprint scripting.

Open your level Blueprint and right click in an empty space. Uncheck the checkbox that says “Context Sensitive” and type “Recapture Sky.” Use this node in conjunction with your level to recapture the sky at a certain point.

Be sure to read the thumbnail warning displayed when you hover your mouse over the node. It lets you know this is a costly procedure!


I hope this gets you the results you are looking for.


Thank you!
A couple of follow-up questions;
1: What if I use a Directional light?
2: Will a reflection capture be able to reflect the light of a dynamic/movable light?

Using a directional light should work fine, and yes it will also capture dynamic movable lights as well.

Ok, any idea what my issue is then?

light from a static point light is reflected in img 1.
light from a dynamic light is not reflected in img 2.

would you mind posting this as a new question on the answerhub or directing me to this question where it was originally posted?

Its kind of the same question, just in different words.
I did start a thread about it in the forums…

Alright, well your issue seems to be specific. Would you mind sending me a copy of your assets or your scene so I can further investigate?

good to know it’s some technical issue on my end:)
Actually I don’t think it’s specifically my assets that are the issue.
I can reproduce the problem in example content from Unreal.

My screenshots are taken from the “Lightroom” example content. I used the glass_flat material as the reflective surface. I didn’t use any custom assets.

What surface/object are you applying the material to?

A static mesh.

Is it the nightmap or the daymap? Is it the wall you are applying it to? Because my flat glass material is translucent and does not have the opaque look yours does.

its the day map. Yes, its the wall mesh. I just adjusted the opacity value in the material to get a clearer view of the issue.

Another issue which might be related(?); Depth of field is not working.
It seems to be working fine in 4.4, but not 4.5. All post process settings except depth of field are showing. I did a clean re-install of 4.5 but no change of either issues… Might be related? I’m stumped…

Probably not. Reflections with dynamic light doesn’t work for me in 4.4 either.

I would be glad to help, but since we seem to be getting away from your reflections issue. Please make a new post as this could be unrelated to your current resolution for this question. I am looking into your reflection problem this morning and will get back to you soon.

Hey again Joki,

So I looked into the reflection capture and I mislead you on the moveable lights being able to be captured. I apologize for the wrong information, but how reflections, more specifically sphere reflection captures, work are they are calculated before run time.

Which means during runtime, unless you have an event tick to update the reflections in your scene, it will not work with moveable lights because they are completely dynamic. Keep in mind if you do this however, it will become very performance costly.

For your other question the reason I ask to make a new post is because there could be other users experiencing the new question you have, and posting it will make it easier for them to search for a solution.

Thanks again,

Another use case solution.
Dynamic real time Reflection in rear/side view mirror while driving Car in VR.
I have been searching for a solution quite some time, so that I can show real time environment reflection in car mirror while driving car in VR. By default the mirror reflective material will show the reflection of sky sphere. If you want to have the environmental surrounding reflection then you can place reflection spheres at certain intervals on your driving path and build reflection capture. When the car goes through these reflection captures then the mirror reflects the reflection capture.
Though it is not completely real time and perfect it might be useful for certain use case after some tweaking. For me it did the job.
!Happy designing guys!