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Imported Alembic animation acts weirdly with scene light

Hi all!
Like the title says, I’ve imported an alembic animation, a catwalk tshirt simulation animation from Marvelous Designer. Everything looks fine except for the behavior of the animated mesh regarding light in the scene. The animated alembic mesh looks like considering only some of the light information about the scene into UE4.

For example, during the animation the garment goes back and forth on the catwalk, but the front side of it remains always more illuminated than the back side even if the garment itself is spinning 180 degrees during the animation. It looks like le lighting informations for the alembic file are kept the same from the first frame to the last, regardless of what is happening during the animation.

I already set all the light sources to movable so the entire lighting is generated in rela time…no baked lightmaps at all, because I already saw that this is not feasible with alembic meshes.

How can i fix this?
How can I make the alembic animated mesh respond correctly to light into UE4?
If you need some image or other stuff to better understand the issue, just ask.

Thank you in advance

I have the same problem with the lighting on Alembic files.
Did you solve this?

-a

I am too struggling with same problem ! , any solution yet ? .

found this solution , haven’t tried it yet though , http://polycount.com/discussion/185297/light-and-shadow-for-an-alembic-object-need-help

I have the same problem with a alembic, I import it as skeletal mesh and there are some bad lights and shadows, if I import it as experimental it It looks good but I can not add it in a sequence and activate the animation.
Ideally, this would work in skeletal mesh, I tried the page sent in the previous message but I do not finish fixing it for the skeletal mesh.

In the image it is not appreciated very well but those shadows marked during the animation are always there, they never disappear when the light hits them full.

Thank you

Hi all! Sorry if I saw only now your messages on this topic.
With the last prpject just finished I didn’t have any issue importing skeletal mesh alembic. It has to be said that I wasn’t importing a complex garment from marvelous designer, but a simple arrows animation from 3ds max.
The workaround I found useful was to export the alembic animated mesh from 3ds max, import it into Blender and than just re-export it. The alembic file created from Blender worked great with UE4, while the original abc from 3ds max give always some problem.

Still have to try with a complex garment from Marvelous Designer though.

Let me know if you find out some way to import correctly abc files from Marvelous.

Can’t find the original link, but I had a similar issue that was resolved by enabling the experimental skin cache feature. Here is the info:
When importing as a Skeletal Mesh, if your animation has big normal delta you may run into issues getting correct looking normals. This is a known issue caused by the way morph-targets can alter the face/vertex normals. As a workaround, you can bypass this problem by using the (experimental) skin cache feature.
To enable this, add the following to your ConsoleVariables.ini file:
r.SkinCache.CompileShaders=1
r.SkinCache.Mode=1
r.SkinCache.RecomputeTangents=1
This should recompile shaders the next time you start the editor. When you open up the Skeletal Mesh asset you should be able to tick the Recompute Tangent option for each material/section.