ue4 reflections boost from emissive?

Count Vader

Ok, so I am working on this concept trying to learn UE4 (I invented this sick new type of game environment, I call it Sci-Fi Hallway)




In the concept, the emissive light fixtures reflect prominently on the floor, and I am trying to reproduce this effect, but it's not working .

With respect to the reflection, Unreal seems to be ignoring the emissive - it is being treated with the same intensity levels as the diffuse components of the materials. Here is a shot (I lowered the roughness of the floor by a lot for this).





And for good measure, a shot in reflections only mode.



You can see that the light fixture are registering, but they are not particularly bright, and the emissive looks like it's being ignored altogether - they seem to be being treated like a white diffuse texture.

Moreover, each light fixture has a corresponding point light with a similar thickness/length to the light fixture, which I had hoped would create a nice reflection on the floor, but doesn't seem to be doing anything reflection-wise

So any ideas?

LMP

You could try lowering the roughness of the floor, how are you feeding the roughness at the moment?

Count Vader

Hmm, well the roughness of the floor is already pretty low.
Currently it's just a bitmap, but I divided it even more to get it pretty reflective.

The problem isn't so much the floor as a whole isn't reflective enough, it's more that it doesn't seem to be emphasizing the lights in the reflection as much as I'd like. For argument's sake, here is a shot with the floor at 0 roughness. You can see the lights are being reflected, but they are not very bright.

Count Vader

Oh, forgot to mention, as this is probably relevant - the floor's metallic property is set to 1/white, so it's a metal material

passerby

If you place a point light where the lights are in the texture, you can give the light a length and radius, for its shape that displays in the reflection.

Count Vader

Count Vader wrote: »

Moreover, each light fixture has a corresponding point light with a similar thickness/length to the light fixture, which I had hoped would create a nice reflection on the floor, but doesn't seem to be doing anything reflection-wise

So any ideas?

Hehe, yep, I really hoped that would do the trick but it didn't

Count Vader

bonus shot of hallway with all the relevant lights selected so that their position and dimensions are visible:







Lit mobility is set to stationary. The reflection appears bright enough when I move the lights very close to the floor, so in theory I could make another set of lights that only affects the floor and exclude them from the rest of the scene, but I don't wanna use a hack like that if there's another way around it.

Another thing I tried is increasing the attenuation radius to include the floor - didn't make a difference.

passerby

Wounder if you cold make something similar to the image reflection cards of udk and place them near the floor.

Count Vader

I guess I'm gonna have to deconstruct the reflections subway scene and see if they're doing anything I'm not -- should have probably done that to begin with.

passerby

Ya it seems like the reflection captures don't gather any HDR data, so won't display above 1 values.

Wounder if there is a way to get the output of the reflection capture, than isolate the high values and multiply them?
I used yo do things like that in udk

Count Vader

Hmm, probably but that seems like that'd be a bit beyond my grasp. It's also weird/annoying cause the lights DO reflect at the appropriate brightness when close to the floor.


However, the Reflections Example page on the unreal documentation site says the following:

Reflections will tend to be more pronounced and apparent in areas where there is a strong sense of overall light and shadow contrast. Just as in the real world, reflections will tend to "pop" in environments that are generally dark in and of themselves, but are cast in harsh lighting conditions. This is why the subway scene used in this example was selected. Being underground, there is no real source of natural light. The few light fixtures are spaced well apart and are rather bright. This means that the pools of shadow and darkness will become prime locations for reflections to stand out to the viewer or player.

So I guess in a clean/bright env like this, I'm pretty much stuck with shitty reflections haha.

ZacD

Random suggestion, try making the white walls and ceiling a bit darker in the BaseColor of the material material. The auto exposure should help it keep from getting too dark.

Also with the reflection capture things, are you using the sphere or box ones?

Count Vader

Well dialing down the intensity of the albedo on the walls and ceiling does help a bit since as you'd except it increases the relative brightness of the lights, but I don't wanna go to dark with the textures (even though I think it looks more cool) since it would a) stray from concept and b) i'm trying to get used to physically accurate workflow, and everything i've read about it, they have made a pretty huge deal about keeping your albedo bright.



And the reflection captures are spheres, there's three of them spaced roughly equally down the hallway.

ZacD

Yeah the floor does have much better highlights, but it is a lot further from the concept, something to keep in mind for future projects definitely.

Try using the box reflection capture, the hallway is more of a box anyway. You could try to play with your exposure/post effects to brighten up the scene, while keeping the base color darker, or maybe make your lights a bit less intense?