Normal map looks incorrect and changes depending on camera direction?

Questions & Answers
1

Here’s a scene with one light, positioned directly above the flat normal-mapped surface. Color map is a single color. When seen from above there are no highlights anywhere:

https://i.imgur.com/H7beMr6.png

Here it is at an angle. Now the highlights are on the wrong edges for the farthest tiles

https://i.imgur.com/huHL11S.png

Normal map looks like this: https://i.imgur.com/FZlVTGD.png
I have set a simple low resolution normal map, using default HDRP/Lit material, and single color base texture.
The material is set to 0 smoothness, so it should be fully diffuse and independent on view direction.
Texture is set to normal map, and point or bilinear filtering both have the same problem.

What’s going on?

2

This is still specular lighting you’re seeing, only so rough that it looks like diffuse lighting. In reality, there’s no such thing as a perfect diffuser, so even though you can set the smoothness to 0 in the editor, Unity caps the smoothness directly in the shader (I think to a minimum of 0.02). Not really sure if there’s anything you can do to change this, other than editing the HDRP BRDF hlsl file and removing the minimum.