Ive been looking around for an answer to this scenario and have found a few different answers that dont quite figure out this dilemma. Ive posted them below:
Resparking the conversation here… Does anyone have any thoughts here? is this a bug? is this never going to happen inside unreal? or possibly in a future release?
Emssive materials do not dynamically emit lighting. They can if you are using Light Propagation Volumes for lighting, but that feature isn’t fully supported and a tacked on solution.
What are you trying to do exactly? There’s plenty of ways to fake lighting.
Hey Zac, Thanks again for your time. I work for a set design company and we are trying to pre-visualize lighting conditions. Except that we have very abstract fixtures, LED panels, etc. What drew me to unreal was the real time rendering aspect but this feature is very important to our work flow. Without it We cannot really understand what is going on in the scene. I know this is a very specific request, for a small part of the user base. Which is why im trying to get to the bottom of the situation
For example. if we wanted to run a chase sequence down an LED strip. It would be more efficient to run a media player with and emissive texture on a mesh than to make 150 +lights in a row. Currently there is no illuminance on other material. I will look into light prorogation volumes a little more deeply today.
BTW, super happy about the media player updates in 4.18!
What I would do is use VXGI–it’s a fully dynamic lighting system that can use emissive textures, it’s not as accurate or as high quality as the baked lighting system but it sounds like it would be the only option for what you want to do. To use VXGI quickly though you’ll need a more powerful computer with a good GPU.
You can check out the thread on getting the VXGI build of the engine here: NVIDIA GameWorks Integration - General Discussion - Unreal Engine Forums
Continuing this conversation. After researching this topic I now understand that this integration takes a level of understanding in software development. It seems as if this option has been available for quite some time, since 2014 if im not mistaken.
Im extra curious, Is this feature ever going to be integrated into the engine or is it such an abstract application that it will never make past the development stage?
The reason I am asking is because it is so necessary for us in our studio, that we will either figure it out the long way or potentially wait for its future release. Im hoping for the latter.
Thank you all for your time again. It has been most valuable.
VXGI won’t be made a part of UE4 by default, what could happen in the future is that Epic could make their own dynamic lighting solution–they originally had one called SVOGI but removed it because many devices (like the Xbox One) aren’t powerful enough to use it. VXGI is better than SVOGI but still has a performance impact so it’s just a matter of technology moving forward.
