Hi there, I’d like to increase the brightness of shadowed metallic objects. I’ve got a default directional light, a default skylight, two grey metallic rods (0.25 and 0.5 roughness respectively) placed in a partially shadowed room. All geometry is static and has sufficiently dense lightmaps. Also, I’m using the lightmass world settings from Epic’s Archviz template.
I’ve tried increasing the indirect lighting intensity of both lights and going through all the post processing volume settings but that didn’t help. Thanks a lot for your help!
Increase the Volumetric Lightmap Maximum Brick Memory Data by at least 2x (it’s suggested in the docs to increase this when decreasing Detail Cell Size to allow enough memory so samples don’t get culled too much or at all nearer to surfaces)
Increase Diffuse Boost, either in world settings or in the materials / details of the objects
See if any of those change it to the intended results.
Thanks for your suggestions but unfortunately the result is the same. I’ve added a third rod for reference. It has the same diffuse color as the other two materials but has a constant of 1 plugged into the specular pin instead of the metallic one.
Do you have reflection captures in the scene (where the reflection is happening!) or you’re using SSR?
You can set the brightness of a metal by setting a brighter base color to it…
…you can also set the brightness of a reflection capture!
I am using a sphere reflection capture and SSR is enabled. Tweaking the intensity, quality, and max roughness in the post processing volume unfortunately doesn’t change much. Unfortunately, neither does the brightness setting of the reflection capture. The base color is already quite bright (0.8, 0.8, 0.8) but bumping it to all 1s of course only makes the reflection brighter. The dark area of the rough metallic material stays unchanged. I’m starting to believe that it’s simply a limitation of UE 4.25 but hope somebody can prove me wrong.
Try enabling AO in Lightmass settings, and then modify these:
Direction Illumination Occlusion - Decrease to lower than 1, at least to 0.5 (probably lower)
Indirect Illumination Occlusion - same as above
Occlusion Exponent - Decrease to lower than 1
Fully Occluded Samples Fraction - Decrease to lower than 1, at least 0.8 (probably lower)
Thanks for the suggestions. Tried enabling ambient occlusion and adjusting the mentioned settings. Unfortunately, not much changed. Would love to know whether the behaviour is the same on Windows.
Is there a post process volume around the area containing the rods? I was working on a 3PS template level yesterday, added a PPV around a mostly enclosed area (similar to yours with one sidewall gone and a floor / ceiling with 3 walls), and no matter what settings I changed, it remained darker in the PPV-covered area. When I changed Blend Weight to 0, it returned to the lighting level it was at before adding the PPV. So a PPV around it could be nullifying settings changes.
Thanks for your effort to replicate the simple scene. I really appreciate it. I’ve gone ahead and placed two smaller reflection captures between the rods so my scene has now 3 captures in total. I’ve also tried setting the SSR intensity to 0 in the PPV (this is the only way how to disable SSR that I’m aware of)… but… same result. Do you mind sharing your sample project with me so I can rerun it? I’m starting to believe this might be a GPU limitation. I’m working on a MacBook Pro equipped with an AMD Radeon Pro 5500M GPU.
Ok, solved it :). There seemed to be a glitch with the engine. I’ve deleted the PPV, the reflection captures, and cleared all lightmaps. Then placed them back into the scene and rebuilt lighting… et voilà, the scene became much like in your screenshot.
thankfully it’s not a limitation…I didn’t think it should result in low quality lighting on metallic surfaces because I’ve seen excellent lighting on metallic / reflective surfaces accomplished in UE
