Moved recently onto the new engine version, and started to notice severe issues with lighting. Yes, I love what you did with static light quality and building speed - it’s really a game changer. Everything is great when scene is completely static.
But, not with movable objects. There is something wrong with Skylight, both static and stationary. It looks like movable objects take too much light information from skylight (or all of it in some extreme cases). In some cases it looks like movable object isn’t affected by surrounding light at all.
Here is how it looks, same scene in .17 and .18:
It looks rather innocent in this case, but in the next example it looks much worse. Scene setup is simple - stationary directional light, static skylight (tested with stationary skylight, but it looks too washed out), no other lights. Provided pictures are taken with deferred shading, forward behaves the same.
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Hi Allottho, Unfortunately I haven’t been able to reproduce this issue. First I tried setting up a simple scene like you did in your first example with a stationary directional light and static skylight with a static mesh sphere set to “Movable.”
Hi!
Okay, here you go. Both projects in one archive. Dropbox - File Deleted
Oops, sorry, it seems I haven’t mentioned, that you have to rebuild the migrated/copied scene with the new volumetric lightmap feature.
And if you rebuild light with volumetric lightmap, have you tried it? If you leave lighting untouched, or if you set lightmass to use old light sample system, it works fine. But rebuild the light - and here it is.
Just tried to create a new project directly in .18. Same issue. But, not exactly. Now there is some kind of a zone around walls, that give off that werid light. And if I’m guessing it correctly, parameter “Volumetric Lightmap Detail Cell Size” will actually affect the size of that zone.
Movable meshes close to the walls or floor (threshold between bright light on the outer side and darkness inside) will be incorrectly lit by the outside volumetric cells.
Logically, the way to bypass this will be to reduce cell size, but I don’t like the warning in the tooltip. 8x memory usage isn’t the way.
Hi Allottho, For some reason when I open up your 4.18 project I can see the lighting issue on the sphere and the closet door, but when I make a copy of your 4.17 project and then open the copy in 4.18, the lighting issue is fixed.
Hello! Is there any news on testing volumetric lightmaps with movable meshes in contrasting bright/dark setting? I still can’t seem to find how to build light in my scene so it looks the same as in previous versions in terms of movable meshes lighting. Can’t design around it by making thicker walls(which works, btw), since I need reasonable transition between interior and exterior.
Here, you can see the results of your test scene after I reduce the Volumetric Lightmap Detail Cell Size from the default value of 200 to 25. This value is the Size of a Volumetric Lightmap voxel at the highest density (used around geometry), in world space units. As you mentioned, this setting has a large impact on build times and memory and should be used with caution.
[Documentation][2]
Alternatively, The Indirect Lighting Cache can be re-enabled by opening the World Settings > Lightmass Settings and setting the Volume Lighting Method to VLM Sparse Volume Lighting Samples.
Thank you! Indeed, that works. Build times are big, but I guess I’ll have to deal with that. As I understand, it generates samples across all geometry under Lightmass Importance? Is there any way to control cell size in different areas of the same map?
“When a Lightmass Importance Volume is
placed, the Volumetric Lightmap builds
bricks that are made up of 4x4x4 cells
(lighting samples). When lightmass is
run, the cells are placed over the
whole Lightmass Importance Volume and
then it uses more cells around static
geometry in the scene to capture
better indirect lighting results.”
The adjustments made in World Settings will end up applying to the entire level, and as far as I know there isn’t a way to control cell size in specific areas but there will be a higher density of cells in the areas surrounding static geometry.
