How do i ger rid of those shadows and why do they appear? They appear only when looking at a mesh from an angle and there is nothing to cast this shadow.
A shadow that only appears at grazing angles with nothing visibly casting it is almost always one of these:
- Shadow bias / self-shadowing: the mesh is shadowing itself. If you’re using Virtual Shadow Maps, select the light and lower the Shadow Slope Bias or check the mesh’s Details > Lighting; with the older shadow maps raise Shadow Bias on the light slightly. Try the console command r.Shadow.Virtual.NormalBias to test.
- Bad or flipped normals/smoothing: if the mesh has hard edges or inverted normals, shading banding looks like a shadow at an angle. Check in Static Mesh Editor with Show > Normals, and re-import with “Recompute Normals” or “Import Normals”.
- Lightmap/Lumen: for baked lighting check the lightmap UVs (Generate Lightmap UVs and a sensible resolution); for Lumen, thin or low-poly meshes can produce leaking/darkening from the distance field, so enable “Generate Mesh Distance Fields” and try Lumen > Mesh Cards.
- A hidden caster: use the viewport’s Lit > Light Complexity / Buffer Visualization > Shadow Mask to see which light creates it, then turn off Cast Shadow on the nearby invisible meshes or the light itself to confirm.
Disable each light’s shadow one at a time and the cause usually narrows down fast. If it persists, post the mesh type and lighting setup (Lumen or baked, VSM or not) and I’ll help narrow it down.
it was contact shadow length