How to prevent lights from leaking between the walls(Planes)?

Questions
1

Apologies if this is a naive question. I am a beginner, trying to create a room with no roof(i.e light coming from sun, directly). I am using a directional light with ShadowGenerator to get shadows of room walls cast on the floor and other walls.
I guess, I was able to create that but there is a slight problem to it which I am unable to figure out how can be solved.

Issue: As you can see from the image below there is a slight leak of light present(between the walls). That is what I am trying to fix(remove).

image
image1920×1080 239 KB

I have tried the following things; some of them have reduced the issue(and the results you can see in the image above) but the issue is not yet completely gone.

  1. Tried joining the walls as a single mesh (did I call out that I am a beginner ?)
  2. Set light.shadowMinZ = 1 and light.shadowMaxZ = 2000; this has reduced the leak(earlier the leak was much bigger)
  3. Tried setting scene.shadowEnabled = true.
  4. Tried setting light.shadowFrustumSize = 18.1 which fixed the leak, but rendered the shadows in incorrect shape.

I wanted to understand how can I fix it, in case if it is not fixable, should the recommendation is to create the room/environment in tools like blender with baked lights and then expert it to babylonjs ?

2

could you recreate the scene in the playground ? I am wondering if increasing the depth of the walls would help ?

3

Thanks @sebavan for the suggestion. I tried that though it has changed the shadows a bit but not completely resolved the issue.

here is the link to the playground: https://playground.babylonjs.com/#T4MAV7#9

4

Is it possible to adjust the bias value of ShadowGenerator?

1 Like
6

Tried changing bias but then it starts showing lines and patterns on the box in the center of the screen

7

changing light.shadowMinZ = -4.5 fixes the issue but changes the shape of the shadow :frowning:

8

It’s good when the shadowMinZ value is -14.5. Maybe the king of shadows can save us @Evgeni_Popov

9

The main issue is the light can not see the thickness of the walls cause it is inside it

image
image1120×880 25.9 KB

you should move it oustide the blocks and ensure some thickness at the angles so instead of a cross shape you could surround your area with thick walls.

2 Likes
10

ok, let me try that.

1 Like
11

Thanks a ton @sebavan for the help. You suggestion has fixed the issue. So when I set the value of light position x to be greater than the wall size(-22 in my case) that fixes the issue. Again, thanks a lot for your help.

1 Like
12

Updated container with fix for reference: https://playground.babylonjs.com/#T4MAV7#10

1 Like