Blender / Unreal ugly shadow

[Nerenii]

Hi,

I’m currently trying to learn the basic concept of light in unreal. To do this, I made a little example with spartial rounded boxes (modeled with blender) but when I build light, the result have some ugly shadows.

I have tried to fix this problem by :

• Increasing lightmap resolution
• Change UV Map Unwrap (blender)
  
  

Nothing works, somebody know how to fix this please ?

Thanks

[ClockworkOcean]

Do you have a lightmap in UE? Take a look at UV channel 1, it should look ‘sane’…

[krhicranes20]

Thanks for sharing this informative and amazing post here. I found it very interesting and enjoy reading this blog. Will wait for more posts.

[Nerenii]

@ClockworkOcean Since my first post, I have change the UV Map.
The UVMap in UE channel 1 looks like this:

And the result after calculating the light is:

I don’t think the UV Map generate is bad, but I have never done a UVMap before so I may be wrong

I will try make the round corner differently (adding quarter sphere instead of using bevel tools) to see if I see any differences.

I am wondering, does the number of island count in a UVMap ? Does this:

and this:

Will result be the same ?
I will try different things and post the results here

@krhicranes20 Thanks for enjoying this post, hope it will helps you

Thanks !

[Nerenii]

Okay so that is the result of my tests

First of all, I have tested 2 differents ways of unwrapping UV in blender with a basic square
Results below:

With only 1 island (2nd picture), unreal generates a stretched UVMap

Second, I tried to make the square with 1 round corner using a quarter of sphere:

(Remark: For this one I didn’t use the Smart UV Project of blender to generate the UV because of the bad UV result it gaves me)

And finally, I tried split the UV into several islands:

(Remark: For this one I didn’t use the Smart UV Project of blender to generate the UV because of the bad UV result it gave me)
The result is better but the shadows are still here

Do you have any idea to remove these shadows ? Are multiple island in UV really the best choice or is it one island and changing light settings ?

Thanks

[Medhue_1 (Medhue)]

@Nerenii

ke the round corner differently (adding quarter sphere instead of using bevel tools) to see if I see any diffe

To me, what I see is likely due to bad, or default normals, or tangets. So, first make sure you have good normals in Blender, and then make sure you export those normals/smoothing in the fbx. I usually use the edge option.

Gyazo Screen Video

[Nerenii]

Thanks to help me. To my point of view, normals of the object are good:

I searched to visualize tangets and only found a way the colorize the object but I didn’t understand if it is good or not

I tried to export the model as you suggested but no change

Thanks

[anonymous_user_f26c856c1 (anonymous_user_f26c856c)]

Hi!

Wherever there is a cut on your lightmap, there is a chance to get an error in lighting! So try to keep as many faces together as possible!!
Also angular islands won’t be calculated in high accuracy unless you pixel/grid snap every outter vertex on the lightmap uv!
My approach would be to leave the separations where they will be less visible… if these cube-y thingies will sit on the floor: cut the bottom rectangle as a separate island, leave the rest together and pull the rest of the 5 sidedes flat! /I don’t know what the skinning option in your 3d app/ …also pixel/grid snapping would help!

[anonymous_user_f26c856c1 (anonymous_user_f26c856c)]

Oh and higher lightmap resolutions also help + adjusted Lightmass settings…

[Nerenii]

@anonymous_user_f26c856c1 I tried your solution and it results are much better than all of my other tests !

Thanks a lot !