Mesh edges showing through the normal map in UE4 [SOLVED]

an173

Hi everyone,

I am having the following problem:

This is my bake in Substance painter



The indented gradient shades nicely here.

The same mesh in UE4




The hard edges in Maya



SP baking settings



I also tried baking in Handplane to a 16-bit tiff, with the same result.

What could be the issue and is this the expected behaviour?

Meshes:

High poly - https://1drv.ms/u/s!AuwURCaONk7jgkhnG0a3DXW9SUQb
Low poly - https://1drv.ms/u/s!AuwURCaONk7jgkrZCgaZOrSXbNCF
Normal map - https://1drv.ms/i/s!AuwURCaONk7jgkkFjCXd9eIUshsw

Thank you

fatihG_

Is this only happnening when the light direction is at a sharp angle?

If so it is a shadow bias artefact. You can play around with shadow bias to 'fix' it.

If it is normal map banding, try manually converting the 16bit image in photoshop to 8bit.

an173

It is most visible when lit at sharp angle, but you can definitely see it with in direct light as well. The material is fully metallic though with roughness set to 0.5 maybe, so I guess it's contributing. It's not really banding, because those are exactly the polygons on the lowpoly mesh that are showing up. I'll try the shadowbias trick, but I am somewhat worried that I already had that set previously to a desirable value in the level for something else..

EDIT

Still visible even with the shadow bias set to 1. It's 0.6 in the original screenshots.

I also tried it with a denser mesh ~1500 faces vs 500. And these smaller faces still show up through the normal map.

EDIT

Changing directional light to stationary solves the issue. Problem resolved I guess.

an173

Turns out this is a known issue:

https://forums.unrealengine.com/unreal-engine/feedback-for-epic/106544-dynamic-shadows-artifacts?133869-Shading-problem-in-4-14=&viewfull=1

JordanN

an173 said:

Turns out this is a known issue:

https://forums.unrealengine.com/unreal-engine/feedback-for-epic/106544-dynamic-shadows-artifacts?133869-Shading-problem-in-4-14=&viewfull=1

Man, was Unreal Engine always full of these graphical bugs? 
Ever since I adopted the engine back at launch, every version had a feature broken by an update.

Makes me wonder what UDK was like, especially when some of these bugs didn't exist in the older engine.