Weird Shading Again

James_1597261

https://prnt.sc/aRxk1rOWUai4

Any ideas why it happens?

 

Is it because the normal direction?
https://prnt.sc/xIPl1ZwxpDHB
How to change the direction?

felis

Based on your normals it looks like you have some overlapping mesh.

Try to select all, then Mesh > Merge > By Distance and see if it didn't remove some vertexes?

James_1597261

0 merge.

James_1597261

I play with the 'Angle' slider on surface pane. If set to 0 the weird shadding is gone.

 

Richard Haseltine

The shading goes because you have removed all smooth shading - not because it has fixed any underlying mesh issue.

James_1597261

I can't find any issue with the mesh.
no double vertices, no face overlapping, no n gon.
Here's the obj.

https://drive.google.com/file/d/1rtHGx_IYU1ucN2Ojn8TuDFp3Q02Uoh9A/view?usp=sharing

 

 

felis

I checked the geometry - it looks fine.

I then did some test. It seems to be the 45 degree angle at the edge of the frame causing that, in combination with sharp edges.

I made a similar frame without the 45 degree edge, and it was fine, but when I added the edge I could see something similar. Removing sharp edges, and introducing a tiny bevel, made it almost not visible.

But none of it is visible in Iray render (or blender viewport), so to me it looks like it is the OpenCL shader DS is using in the viewport that have an issue.

James_1597261

Ah... okay, so that's why. At least I can sleep tonight.