Building lighting at 99% for days [bug?]

Wowthever · January 12, 2015, 12:56pm

Hi to all. The editor is building the lighting of my project, and it has been stuck at 99,52% for more than 24 hours long (light building started around +40 hours ago). Swarm Agent seems to be working, but I don’t know if rendering it’s going to be finished in a reasonable time or if I should stop it and restart it with other lighting settings.

The scene is semicomplex, with a big ammount of repeated assets, expensive shaders and high resolution lightmaps, but it’s not something out of the ordinary. The scene has a lightmass importance volume and is being lighted by a single stationary sunlight. Lighting and world settings are set exactly in the same way as shown in the showcase Berlin flat.

I built the lighting in this same scene with the same settings as I was starting the project and with a simpler environment, and it lasted about 10 minutes. So I don’t know why it’s now stuck for more than 24 hours at 99%. I mean, even raytracing would have been faster, so I think that, either I’m doing something wrong or that’s a software bug

Advanced thanks.

Here’s the log:

18:30:43: [Interface:TryOpenConnection] Local connection established
18:30:43: [Job] Accepted Job CA8F76EB-431C738D-5A2DC8AD-37CCE56E
18:30:50: [Job] Launched Job UnrealLightmass_2014-12-21_21-08-42_1138176-64bit.exe
18:30:50: [Job]     PID is 6584
18:30:50: [Job]     GUID is "CA8F76EB-431C738D-5A2DC8AD-37CCE56E"
18:30:50: LogLightmass:Display: Lightmass Win64 started on: DANIEL-PC. Command-line: CA8F76EB431C738D5A2DC8AD37CCE56E -numthreads 3
18:30:50: Lightmass Win64 started on: DANIEL-PC. Command-line: CA8F76EB431C738D5A2DC8AD37CCE56E -numthreads 3
18:30:50: LogLightmass:Display: Processing scene GUID: CA8F76EB431C738D5A2DC8AD37CCE56E with 3 threads
18:30:50: Processing scene GUID: CA8F76EB431C738D5A2DC8AD37CCE56E with 3 threads
18:30:50: Building static lighting...
18:30:50: LogGenericPlatformMisc:Warning: Failed to determine engine directory: Defaulting to ../../../Engine/
18:30:50: Failed to determine engine directory: Defaulting to ../../../Engine/
18:30:50: [Job] Found a parent connection for PID 6584
18:30:50: [Job]     237916FB -> 1D3EC401
18:30:50: [Interface:TryOpenConnection] Local connection established
18:30:50: Measured CPU frequency: 3.39 GHz
18:30:50: FStaticLightingSystem started using GKDOPMaxTrisPerLeaf: 4
18:30:50: Number of texture mappings: 410
18:30:50: Number of fluid mappings:   0
18:30:50: Number of landscape mappings:   0
18:30:50: Number of BSP mappings:     0
18:30:50: Number of static mesh instance mappings: 410
18:30:50: Reserving memory for 410 meshes, 338947 vertices, 398493 triangles
18:30:50: Scene surface area calculated at 1410.449 million units (274.027% of the estimated 514.713 million units)
18:30:50: Importance volume surface area calculated at 1410.449 million units (282.219% of the estimated 499.771 million units)
18:30:50: Preallocated 0.1Gb for kDOP nodes and triangles
18:30:51: Building kDOP took  0.32 seconds.
18:30:51: Static lighting kDOP: 262160 nodes, 131081 leaves, 524324 triangles, 332934 vertices
18:30:51: Static lighting kDOP: 24.755% wasted space in leaves
18:30:51: kDopTree.Nodes        :    28.0Mb
18:30:51: kDopTree.SOATriangles :    36.0Mb
18:30:51: kDOPTriangles         :     0.0Mb
18:30:51: TrianglePayloads      :    12.0Mb
18:30:51: MeshInfos             :     0.0Mb
18:30:51: Vertices              :     5.2Mb
18:30:51: UVs                   :     2.6Mb
18:30:51: LightmapUVs           :     2.6Mb
18:30:51: Static lighting kDOP: 262160 nodes, 131081 leaves, 524324 triangles, 332934 vertices, 86.4 Mb
18:30:51: Processing...
18:30:51: EmitDirectPhotons complete, 0.197 million photons emitted in 0.3 seconds
18:31:26: EmitIndirectPhotons complete, 6.770 million photons emitted in 34.0 seconds
18:31:27: Marking Irradiance Photons complete, 0.377 million photons marked in 0.2 seconds
18:34:26: Caching Irradiance Photons complete, 15.467 million cache samples in 179.9 seconds
18:37:24: Calculate Irradiance Photons complete, 0.223 million irradiance calculations in 177.2 seconds
19:00:11: Lighting 10.9%
19:42:14: Lighting 20.0%
20:31:00: Lighting 30.0%
21:14:55: Lighting 40.1%
22:05:40: Lighting 50.1%
23:01:39: Lighting 60.1%
23:57:07: Lighting 70.1%
1:42:09: Lighting 80.0%
3:10:40: Lighting 90.0%

Robbie222 · January 13, 2015, 10:07pm

Hi,

I had the same problem. Here is what I did:

1.New empty level ( for faster testing )

2.Grab first half amount of meshes from CB and throw them in the scene > Build light. If it works then it means you the problematic mesh is in the 2nd half.

Grab next 50% of the 2nd half meshes and repeat the process until you find the mesh causing the problem.

For me the problem was that UE4 wasn’t generating a lightmap for a complex mesh of 100k +polys.

Hope this helps,
Robbie

Wowthever · January 13, 2015, 11:17pm

Thanks Robbie, I will try it and see if I detect wich asset is causing the problem (I’m suspecting of a static mesh I use as a snowy terrain instead of the integrated terrain tool, because of tesellation/displacement purposes).

unit23 · December 27, 2016, 1:20pm

I had light build also stuck at 99%. Turned out was related to foliage with over 256 lightmap resolution.

unit23 · December 27, 2016, 1:21pm

I had light build also stuck at 99%. Turned out was related to foliage with over 256 lightmap resolution.