Download

Movable Doors not Affected by Lightmass

Development Discussion Rendering
#1

Hello there,

I am currently working on an ArchViz Project which has Doors that are controlled via Blueprints and Overlap/Trigger Volumes…
Lighting with Directional Light, Sky Light and fill Point lights and indirect Lighting Setups as Koola “created” …

Everything looks fine, but because the Doors are set to “Movable” they are not affected by the Lightmass…
I tried activating “Light as if Static” but because in the closed state at the beginning the door goes into a crease in a wall it has black edges that become visible when the door opens…
Also tried around with the Indirect Lighting Cache but that didn’t really work out either…

How can I get this to work? I could try something like an emissve material but that is quite dumb… any other ideas?

TL/DR: Question: How do I get a movable Door to be affected by Lightmass / have similar lighting as the objects around it?

Thanks and Greetz,
JayCox of on3studio

#2

what stops you from baking lightmass with the door in open state and moving it to the closed state with blueprint when the “game” starts? still won’t be perfect but there is next to no chance for you to get a dynamic situation like that with static lighting on the moving objects looking perfect.

#3

Hi Divi,

yeah thought of that too and am going to try it out now! Thanks for the input :slight_smile:

Anyone else a possibilty in mind?
Greetz,
JayCox of on3studio

#4

Well it’s got an up and a down side…
On the one hand, lighting looks quite good with baking it while a slight bit open and then closing it on “Begin Play”… but the problems are two:
A) Now I obviously have little black parts on the door where it is inside the wall while being baked and B) I don’t get dynamic sun shadows anymore… :frowning:

There has to be a decent way of combining this…

EDIT:// I remember Koola doing a sun timelapse by baking a map for each “frame” so to speak… Can I tell the door(s) to bake their various states? I have the animation via triggered blueprints…

Thanks again?

#5

Koola’s timelapse did not use baked shadow maps, but rather it was using LPV. That wouldn’t even work correctly for what you want because it would need not just the closed an open lightmaps but lightmaps in between, and the lighting change would affect many other lightmaps too. Doors are actually a big problem to do without a good fully dynamic lighting system. What’s done with UE is that dynamic objects get a light probe that adds indirect lighting to the dynamic object to make it look like it matches the lighting around it, but that doesn’t work well for doors because the lighting on one side of the door can be drastically different from the lighting on the inside. LPV is a possible solution but it is very limited with lighting compatibility and the quality is very poor.

#6

Any new ideas about this topic? Because I have reached a stage where this is one of the last but quite major problems… And I still have no idea how to properly do it :frowning:

#7

No, there’s no change. Animated objects are always an issue with getting good lighting, doors are more difficult because of how they need to open and close and have different lighting on each side.
The only thing that will make the lighting of a door match everything else is to use a fully dynamic lighting system, which won’t look as good.

#8

You can also use a smidge of heightened ambient occlusion on the door in question to fake bit of light.

I had to do this on some trim in a room once and it worked quite well. You’ll have to tweak it a bit - if you want to get really involved add some specific materials with AO gradients made to fake light direction.

#9

So there is no workaround to using fully dynamic lighting with openable doors in the scene?

#10

If you have enough volumetric light map samples it should look alright, https://docs.unrealengine.com/en-US/Engine/Rendering/LightingAndShadows/VolumetricLightmaps/index.html

#11

Many thanks. I remember now watching this in tutorials but forgot. I guess you can’t remember everything unless you put it to use in projects.