Casting light without surface to cast light on

Development Rendering
1

Hello. What is the best way of display light without any surface to cast light on? I want to display light cone but I don’t want any wall behind my light emitor.

This is more understandable in pictures:

sn__mek_obrazovky__28_a_1024.png
sn__mek_obrazovky__28_a_1024.png461×1024 457 KB

First picture: There is no wall between cube and horizontal pipe visible behind the cube. Light is on, but has no sufrace to be cast on.

Second picture: There is wall between cube and pipe. Light cone is visible because is casted on wall.

Third picture: This is what I want. There is no wall between pipe and cube, still light cone is visible.

I don’t have a surface behind cube but i want light visible. I would like to cast shadow by moving the cube.
If I use static mesh I will need to place surface behind the cube.
I tried use particle system like light emitter but this seems to be very ineffective.

What is best way to achieve this effect?

2

What you ultimately want is volumetric lights, which aren’t available in UE4 yet–it’s one of the next-gen type features.

3

Thanks for you reply.
What would you recommend to use instead of volumetric lights ?

4

Can you make like a partially transparent static mesh in that conical shape you’re going for? I think that’s how it was done in the ye olde days.