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[Lightmap Issue] - Huge difference on lightmaps depending on Level. [Solved]

polycounter lvl 9
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EliasWick polycounter lvl 9
Greetings, different levels (maps) give me a huge variety in the quality of my lightmaps. Can someone guide me to what the issue might be?

Here are some images to show you my problem:
  • My mesh lightmap UV's, lightmass settings and how the front side of the mesh looks on all levels:



  • Using the FirstPersonTemplate (How I want it to look)


  • Using a New Level (Default) with the exact same settings as in the FirstPerson Template:


  • Using a New Level (Default) (I have not modified anything in the scene, except for adding the models and applied a white material)


Replies

  • EliasWick
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    EliasWick polycounter lvl 9
    Solved it: This is a known issue when using the modular elements. You need to decrease Static Lighting Level Scale to 0.1 and increase Indirect Lighting Quality. You will then get more samples of the light and the light will be built more accurately.

    Source: https://answers.unrealengine.com/questions/445263/problem-with-lighting-and-modular-wallsseamsclippi.html

  • IacopoAntonelli
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    IacopoAntonelli polycounter lvl 3
    Elias, increasing Static Lighting Level scale will make your building times really higher. I suggest you to merge the pieces together once you finish your level and set this about 0.5 or another value that fits your needs.
    I am using this technique for our open world game building and It's way better from building lightmaps on modules.
    Build time will be reduced a lot when merging all the pieces into some bigger ones, and this will make your map file size lower:
    for example if you have a room composed by let's say 16 modules (floors and walls) with a lightmap of 128-256 for every piece, merging them in a single piece will let you build a single static mesh with a lightmap of 512/1024.
  • cptSwing
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    cptSwing polycounter lvl 11
    ^ Does merging have an effect on culling, though?
  • Obscura
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    Obscura grand marshal polycounter
    Yeah they wouldn't cull the same. What I would rather suggest is to merge it into medium size pieces. Then it can cull some, and bake better as well.
  • EliasWick
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    EliasWick polycounter lvl 9
    Greetings everyone, thanks for all the comments, I am still experimenting with the final output. It's either better culling or better lightmaps in this situation. I believe that IacopoAntonelli's has the correct answer though. The smartest way would be to merge everything together and build it that way. There really is no reason to why I should keep all the pieces separated. Thanks for the help.
  • Obscura
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    Obscura grand marshal polycounter
    By "medium size" I meant like a long wall would be one piece. But not a complete room with all of its walls together, but maybe even that. Then you can also just press weld to save some verts.
  • EliasWick
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    EliasWick polycounter lvl 9
    Hey Obscura, I almost didn't recognize you with the new Thumbnail or Avatar, whatever they call it these days! ;)

    I get what you mean. I recently started a new project and before I start creating the world I had to figure out some things and lightmaps were among those things. So I created a couple of small wall pieces to test out the capability of the lightmaps, and got the result you can see above.

    I know how I want to work with lightmaps now, and I am getting pretty decent results.
    Here are some information for those interested, even though it's pretty useless:
    • I am only using one Light Source
    • Lightmass Settings are default except settings below:
      Static Lighting Level Scale= 0.1
      Num Indirect Lighting Bounces = 100
    One model per room (total of 6 models) took 106 seconds to build.
    Each room has a lightmap resolution of 128.

    One big model with all 6 rooms welded together, took 254 seconds to build. (You can more or less cut the time in half if I were to use a 512.)
    This big model has a lightmap resolution of 1024. (Using a lightmap resolution of 512 looks fine too).
    Setting Static Lighting Level Scale to 0.1 was unnecessary when using one big model since everything is smooth by default and looks decent. To improve darker areas I would have to bump up Indirect Lighting Quality and smoothness which I will do at a later time.

    EDIT: Also worth noting, I have not placed my model / polygons "on the grid". I used the default 3Ds Max Pack Normalize with a padding of 0,07. The result will be more or less the same (knowing this from testing.)

    Result as of now using 1024 with one big model:


    Thank you all!

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