baking normal from high poly to low poly made with instantmeshes issue

Question

I made a high poly sculpt and I have used instant meshes to do the automatic retopology to get my low poly mesh.

the high poly:

The low poly, we can see the quads and it is not possible to use the smooth shading on it

Then I create an UV image, unwrap the low poly on it. save the image, create a material for the low poly, open the low poly image on the node editor

select the High poly and then the low poly, set baking option to normal and check "selected to active" and add a bit of ray distance

but I get normals like this:

and if we zoom in we can see the quad of the low poly

Is there something I have done wrong ? Is it the unsmooth lowPoly who cause troubles ? Is it possible to have smooth shading on the low poly from Instant meshes ?

Answer 1

The issue is within the exported low poly mesh, Instant meshes generates sharp edges and custom split normals data to the new generated mesh.

The solution is simple: In edit mode select all edges and click Ctrl+E and select clear sharp. If that doesn't smooth the object you can click the 'clear custom split normals data' in the object data properties under geometry data. Don't forget to check autosmooth angle and shade smooth/flat.

Hope it helps.