Low, Medium, High Poly Model - Separate Normal Maps or Not?

Unity Engine
1

Hi there! I just have a question which I hope would be easy to answer.

Let’s say that in my game, I want the player to be able to choose his graphical settings: Low, Medium, and High. I made an experimental model in Zbrush with 6 subdivisions. The lowest (subdiv 1) is 2K poly, the medium (subdiv 2) that I want is 7K, while the highest that I want (subdiv 3) is 30K. The one in subdiv 6 is 1.2 million poly, so obviously that’s not a good thing to use in games.

Zbrush Jumper Jaw 2K

Zbrush Jumper Jaw 7K

Zbrush Jumper Jaw 30K

Zbrush Jumper Jaw 1.2M

The question is, will the normal map that I made from the lowest subdivision also be applicable to the medium and high models that I chose, or should I make separate normal maps for each of the models?

When I rendered out pictures (on 3DS Max 2013) using only the normal map that I made from the low poly version, all three model versions (low, medium, high) don’t seem to look different from each other at all. I think there’s a tiny difference in color but I’m not too sure, I don’t have the best eyesight in the world.

Low with Normal Map:

Medium with Normal Map:

High with Normal Map

Anyway, thanks to whoever can answer my question:smile:

(I think it’s a good thing that even the low blocky version, when applied with normal map, looks similar to the high version.)

2

As long as you have properly unwrapped the models uv you shouldn’t have any issues applying them to your low resolution meshes, or using them for any of your higher resolution meshes. At certain levels of mesh resolution it is unnecessary as detail is derived from physical topology rather than a normal map as the higher resolution meshes are what you use to generate said normal map.

I would recommend only using the lowest resolution model and then using the normal maps you have generated for it. Also remember that normals should be smoothed, and applied to the tangent space in a bump value.

3

Thank you very much, that cleared up the doubt that I had and saved some time :slight_smile: