Search in
Sort by:

Question Status:

Search help

  • Simple searches use one or more words. Separate the words with spaces (cat dog) to search cat,dog or both. Separate the words with plus signs (cat +dog) to search for items that may contain cat but must contain dog.
  • You can further refine your search on the search results page, where you can search by keywords, author, topic. These can be combined with each other. Examples
    • cat dog --matches anything with cat,dog or both
    • cat +dog --searches for cat +dog where dog is a mandatory term
    • cat -dog -- searches for cat excluding any result containing dog
    • [cats] —will restrict your search to results with topic named "cats"
    • [cats] [dogs] —will restrict your search to results with both topics, "cats", and "dogs"

How do I get rid of blotches/artifacts in interior scene?

Hi Guys, I am new to unreal and I am trying to learn how to create interior archviz scenes. I have been learning without any problems until now... While I was lighting my scene have come across weird dark blotches on only some objects in my scene. I have looked around for similar problems but all their fixes haven't worked for me... I have played around with the lightmass settings, but increasing the indirect bounces didn't seem to help a thing. All my static meshes have a high lightmap resolution, so that shouldn't be a problem either. At the moment I have no clue how to fix this, so if anyone could help me out that would be amazing! Below I put some pictures and also the lightmap settings!

alt text

alt text

alt text

alt text

alt text

Product Version: UE 4.21
screenshot-5.png (50.9 kB)
screenshot-1.png (1.6 MB)
screenshot-2.png (1.3 MB)
screenshot-3.png (1.2 MB)
screenshot-4.png (297.9 kB)
more ▼

asked Jan 12 '19 at 10:33 PM in Rendering

avatar image

6 1 3

avatar image Jacky Jan 12 '19 at 11:49 PM

High lightmap resolution is a relative concept. For instance if you have all of the walls as a single mesh, even 1024 may not be enough so you need to split them and repack their UVs. Also make sure you have a lightmass importance volume covering the whole building.

avatar image MemesAreDreamz Jan 13 '19 at 12:40 AM

Hi Jacky, Yes I do have a lightmass importance volume covering the building, so that shouldn't be it! However, the outer walls are one object so I'll look into that! The only thing still confusing are the small drawers and all the interior walls, they are rather small single objects with a high lightmap resolution (I have checked in the debug view and it is more than enough) but they still have weird artifacts... Do you think it might have anything to do that I imported the model from sketchup? And if yes are there any steps to look out for when importing?

avatar image Jacky Jan 13 '19 at 12:47 AM

Maybe. First thing to check is the UV's of those meshes. They should occupy as much UV space as possible, so i'm guessing currently they are each packed at a small portion of the UV space so lightmap resolution isnt sufficient. Dont try to increase the resolution anymore, proper UV's is common practice. Feel free to post screenshots of the UV's if you need more advice.

avatar image MemesAreDreamz Jan 13 '19 at 12:55 AM

Thanks so much, I'll get on it soon!

avatar image MemesAreDreamz Jan 13 '19 at 01:05 AM

Alright so those are the uv's from some of the meshes, they all fill out most of the space, apart from the walls, which I will still change! alt text

alt text

alt text

screenshot-7.png (282.6 kB)
screenshot-8.png (462.5 kB)
screenshot-9.png (500.2 kB)
avatar image Jacky Jan 13 '19 at 01:10 AM

Ok, UV's look fine but 64 is pretty low especially for the second and third meshes. go up to 256 and see if quality improves.

avatar image MemesAreDreamz Jan 13 '19 at 01:12 AM

Sweet I'll give that a shot!

avatar image MemesAreDreamz Jan 13 '19 at 01:38 AM

So I changed the resolutions but there is no change at all.. also here is a picture of the lightmap density! alt text

alt text

alt text

avatar image Jacky Jan 13 '19 at 01:50 AM

Hmm, can you try to set Indirect Lighting Smoothness back to 1 and try again? And make sure you aren't overriding lightmap resolution in the level. If it's still a no-go could you upload the project or just the fbx wall meshes for me to check out?(google drive, dropbox, etc.)

avatar image MemesAreDreamz Jan 13 '19 at 02:10 AM

Yeah I'll give that a shot too! If that doesn't work i'll send you the file! :) Thanks so much for the help btw really appreciate it!

avatar image MemesAreDreamz Jan 13 '19 at 02:49 AM

So, I have done all that and split the walls in separate pieces, but the problem still persists sadly... I will be uploading the file to google drive soon!

avatar image MemesAreDreamz Jan 13 '19 at 03:08 AM

The drive link is: https://drive.google.com/file/d/10NVZMJcYZXA3VvwzKx3rasMQrRv5V-M0/view?usp=sharing It is a 7zip file to reduce size! Just unzip it and it should be good to go! To find the right scene, look for the folder: Scenes In there should be a map called "test"! (I know.. very original)

(comments are locked)
10|2000 characters needed characters left
Viewable by all users

1 answer: sort voted first

Well it was almost driving me nuts but it couldnt... hah!

I suspected some "invisible" meshes when i saw those shadows near the ceiling after i took a build:

alt text

Couldnt find and select them until i switched to Player Collision View Mode. The level at this angle looks like this:

alt text

And looks like this in player collision mode:

alt text

Looks like some meshes got messed up while exporting from sketchup. I've never used sketchup but whenever i got a model from there into 3ds max i've always had problems, so i dont know how you'll fix them i'm afraid. :\ But you can at least start finding&deleting problematic meshes in player collision mode. You'll need to move the camera around because they keep flickering. Messy problem, but luckily you ran into it with a simple level like this one.

lightweird3.jpg (46.3 kB)
lightweird2.jpg (68.8 kB)
lightweird.jpg (42.5 kB)
more ▼

answered Jan 13 '19 at 04:16 AM

avatar image

16.8k 671 167 677

avatar image MemesAreDreamz Jan 13 '19 at 05:24 AM

First of all thanks a lot for all the time and effort you put into this! Really appreciate it! I might have a suspicion what the big black part is. There used to be a floating shelve fixed all along the ceiling, which I ended up removing as it just looked weird.. maybe somehow unreal still recognises it while it generates the lightmaps. I will reimport the mesh again and try to clean it up as good as I can.. I have realised that the sketchup import creates a lot of unnecessary meshes that might cause the problem, so I will try to keep it simple from now on! A potential fix I have just discovered is to set the lighting quality to production... it helps with some of the black artifacts, especially the ones in the kitchen at the drawers. For the other artifacts still left creating dim point lights at those areas retouches some of the blotches, not the best and cleanest solution, but better than having the blotches. Another solution that might work will be to import it directly with datasmith.. At the moment I am using blender to convert the sketchup .dae file to an fbx, but this isn't very clean and might cause some of those problems. The only downside for the datasmith solution is that it requires sketchup pro, which costs a lot of money.. I will get that though when I have a student id to get the student version which is just $70 nzd which is alright I guess. Anyways I will still play around with some settings and watch some tutorials to learn all the stuff behind lighting! For now thanks so much for your help and if you by any chance have any ideas feel free to let me know! Cheers, Laurin

ps: here are some screenshots of how it looks on production settings with the point light in place!

alt text

alt text

avatar image Jacky Jan 13 '19 at 09:10 PM

Ahh, build quality is the most basic thing, i should have asked that first. My mistake. :\ And yeah, those shelves still exist in a crazy exploded form so they are being calculated for lighting as well. So getting rid of them will give you less headaches.

I havet used datasmith myself and i doubt that it'll fix such issues, but it is worth a shot if you have no other option.

avatar image MemesAreDreamz Jan 14 '19 at 02:26 AM

Yeah I think sketchup really isn't the best program for asset creation I guess. For my next project, I'll just make sure to combine all the meshes as one for each object and name them well so if something goes wrong I can easily find the problem!

(comments are locked)
10|2000 characters needed characters left
Viewable by all users
Your answer
toggle preview:

Up to 5 attachments (including images) can be used with a maximum of 5.2 MB each and 5.2 MB total.

Follow this question

Once you sign in you will be able to subscribe for any updates here

Answers to this question