x

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"

Shadow spots and light bleed.

Hi! I'm figuring out how to properly bake light in ue4. And right now I stumbled upon a bit of an issue. I have this small scene with nothing (so far) else than walls, a door and a window. Everything has custom made lightmaps.

After building light in ue4, I'm getting artifacts all over the place.

As you can see here, there are dark spots on the door, and light bleeding on the wall. alt text

Some more bleeding around the window. alt text

My lightmap density is set to optimal values. alt text

Just to make sure, there are no lightmap errors anywhere (and you can see all the artifacts even better in Lighting only mode). alt text

I've watched a recording of UE dev stream where they were talking about lightmaps. And they were using even smaller lightmap density than I do (they had everything in blue tones). Yet, my results are much worse than the developers had on stream, somehow.

What could I be doing wrong here?

Product Version: UE 4.16
Tags:
light-bleed.jpg (440.6 kB)
more-bleed.jpg (411.5 kB)
error-coloring.jpg (240.3 kB)
more ▼

asked Jun 09 '18 at 05:06 PM in Rendering

avatar image

Kligan
56 12 15 23

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

4 answers: sort voted first

Ok, so, I've spent an entire day googling, studying documentations and watching Unreal Engine dev streams recordings.

And here's the rundown of what I found.

The important settings, that rarely being mentioned or explained well, can be found in World Settings tab.

Static Lighting Level Scale, Indirect Lighting Quality and Indirect Lighting Smoothness. The best way to learn how to properly set them up is to watch this video I found. This is the most helpful thing ever!

HOWEVER! Now that my static lighting is all fine and dandy, I'm having another issue, and can't seem to find solution anywhere. Only couple mentions on forums, but that's about it. Here's what I mean: alt text

As you can see, my movable objects are MUCH brighter than static ones. I've covered up the bottom of the scene, so no light should be bleeding in. All walls are covered up as well. Volume Light Sample Placement Scale is set to 0.5 with Static Lighting Level Scale of 0.1 (as you can see on the screnshot, it is pretty dense). Sky light intensity is 1.

I've tried to tweak things this way and that way... But can't seem to figure out why all the movables are glowing so much? And yeah, they are using the same material as static meshes they "attached" to.

movables.jpg (460.7 kB)
more ▼

answered Jun 10 '18 at 07:50 PM

avatar image

Kligan
56 12 15 23

avatar image Kligan Jun 10 '18 at 11:08 PM

Ok! I solved this issue as well!

In my case, it was actually the opposite of how I was trying to solve it. I was attempting to increase the Volume Light Sample Placement Scale in hopes that it will help. As you can see on the previous screenshot, the amount of samples is way too high. And it seems like it makes the engine confused.

I reduced the amount of samples until all objects were lit more or less correctly. For my scene with Static Lighting Level Scale of 0.1, the Volume Light Sample Placement Scale is set to 1.5 on this screenshot: alt text

fxd.jpg (459.2 kB)
(comments are locked)
10|2000 characters needed characters left
Viewable by all users

I tried to separate the window mesh into several pieces - frame, flap, glass and sliding lock. UV'd lightmaps for each of the pieces separately. Imported them individually into the engine. Combined together into blueprint. Build the lighting... and it still happens! alt text

Even when I crank up lightmap density so much that it appears as blinding red in Lightmap Density view, it still gives me shadow bleeding everywhere!

My next step was to remove my lightmaps and allow unreal to generate its own. Still the same bleeding in the same spots.

Please, help! I've no clue what else to do...

spots.jpg (314.5 kB)
more ▼

answered Jun 09 '18 at 07:06 PM

avatar image

Kligan
56 12 15 23

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

Hi!

Could you show us your lightmap uvs please? I'm guessing that your lightmap resolution is low (you can see the distorted shadows on the wall) you have cuts in your lightmap uvs where you shouldn't have and your edges are not snapped to pixel/grid!

more ▼

answered Jun 10 '18 at 04:59 PM

avatar image

Makigirl
1.3k 5 4 8

avatar image Kligan Jun 10 '18 at 07:33 PM

Hi, Makgirl! My lightmaps are clean and crisp: alt text

Yes, the resolution is low, but it is optimal if you look in Lightmap Density mode. Lightmaps were not the issue, as it turned out. I will post the solution in a separate comment, so I could mark it as an answer for people, who might stumble upon the same issue.

However, I'm still having some troubles, and if you could maybe take a look at it, that'll be great! I'll post it in the next comment as well.

lmps.jpg (442.4 kB)
(comments are locked)
10|2000 characters needed characters left
Viewable by all users

Please teach us...

more ▼

answered Jun 10 '18 at 07:43 PM

avatar image

Makigirl
1.3k 5 4 8

avatar image Kligan Jun 10 '18 at 07:55 PM

I've posted my finding and new questions up above ^ :)

(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