Normal map baking artifacts

Dino97

Hello,I am having problem with baking a normal map, I dont know much about models and baking,and I couldn't find any answers on google.

My shading is set to smooth on my low poly mesh,since it is a flat surface,with that setup I get artifacts on my normal map.


When I set it to smooth,there is no artifacts but the flat surfaces are not looking good

Here is my model in wireframe if it can help.

StevenTB

There are a couple of threads on normal mapping on the technical talk forum that helped me a great deal in understanding what is going on. This is a huge topic, and a lot to take in. It will take time to figure out how things work, why you should do things in certain ways, and how they relate to Blender.

http://polycount.com/discussion/81154/understanding-averaged-normals-and-ray-projection-who-put-waviness-in-my-normal-map/p1
http://polycount.com/discussion/107196/youre-making-me-hard-making-sense-of-hard-edges-uvs-normal-maps-and-vertex-counts/p1


The image on the left shows Blender with flat shading, the image on the right is Blender with smooth shading.
http://wiki.polycount.com/wiki/Texture_Baking#Cages

This is why you see the triangle artifacts in your first image, there are gaps and overlapping details because each face of the selected mesh is projecting it's own version of the high poly normals.

With your second image the normal map is trying to overcome the base meshes normals(The large triangle shading on the side) Trying to add sharp edges, and add the little details aswell.

Blender is a great program, but to get good normal maps you really need another solution, such as xNormal. I suggest you grab that and watch some tutorials for using it. By using xNormal and an avereaged cage mesh you can get the benefits of both sharp edges on the low poly and clean baked information.

Give it a go, ask questions

Dino97

Thank you for your answer, those threads have a lot of information and I hope I will find what I am looking for
As for xNormal,I am using it for some time already and I tried baking both in blender and xNormal,it gives me almost same result. I am not sure if its a cage problem since I never used it before. I hope those threads will help.

Thanks again

Apocrs1980

I got a similar result when I was messing with the export settings in zbrush with the offsets. to fix it I just made sure both hi and low polys offsets were exsactly the same.

I confirmed in 3d viewer on xnormal that both meshes were occupying the same space.

And if using a cage made sure it just bearly was covering both meshes having no protrusions.
That fixed the problem for me.

StevenTB

Hey Dino97 - Check out this video too, this is one that helped me a lot with regard to Blender and the other two threads.

https://www.youtube.com/watch?v=xkES2oodLhw

Dino97

Thank you both for your answers, the video helped me get rid of some artifacts after setting the cage correctly(I was doing it all wrong), as for the triangle artifacts, I added aditional geometry, set smooth shading and got better results.

Thank you all for your answers