UE5.1 PostToon Issue

[ReToei]

Hello! I am trying to set up PostToon on my character by following these guide: https://ruyo.github.io/VRM4U/02_toon/ And I cannot get the same result as in the examples given on the website.

For some reason my character's shadows are not displayed, only highlights are displayed (I repainted the highlights to red to make them more visible)

I will tell you about the order of the things I do:

1. I import a standard vroid character into UE5.1 using the MToon Unlit option
2. I Put the skeletal mesh of this character in the scene
3. I Put BP_PoseCopyToon into same scene
4. In BP_PoseCopyToon I set target actor to my character skeletal mesh

And after that my model gets only highlights but no shadows. If in BP_PoseCopyToon, in set target option I replace my model skeletal mesh with SK_VRoidSimple then it is working but only with this model.

Also, if I turn on options Debug Draw Shadows or Debug Draw Raw on my custom model, they look right: But the model still doesn't get those shadows that are visible when option Debug Draw Shadows is on

It would be great if you could share more detailed instructions on how to use PostToon to make the custom model work properly with it. Unfortunately, there is too little information about it on the documentation site.

Thank you in advance for your time!

[ruyo]

Hi. That sample model in VRoid have no shadow color set. Please try to set it in VRoidStudio or set the multiply parameter to the shadow color in the adjustment panel of VRM4U. Thanks.

[ReToei]

Thank you. @ruyo Now the shadows are working. But now I have problem with ugly face shadows. I have adjusted the face normals in blender so that they are flat and the shadow is flat, but UE seems to ignore these normals and uses some other normal calculations.

Is there any way to use the new normals to display the shadow nicely?

[ruyo]

The shadow in that screenshot is a cast shadow. It is a shadow that is cast by the shape of the 3D model, regardless of the normals. It is difficult to deal with fundamentally. You can avoid it to some extent by turning off shadows only for the face in the SkeletalMesh settings. Also, you can avoid it to some extent by not setting the shadow color for the face.