Author Topic: Normal black and white dots  (Read 1789 times)

Hello, community! :)

So I finally decided to learn sd after few attempts in the past, haha. And tried to create my first material, snow, pretty simple and yet I encountered a problem that I can't solve myself.

Snow sparkles. I used white noise > histogram scan (to reduce the amount of noise) > convert to normals > and few more tweaks to create random directions of the pixels, then I connected all this to roughness and normal outputs to imitate sparkles on the snow, everything works fine, sparkles reflecting light from different angles as they should, but this black and white dots, they look like they are painted no matter from which angle I look at them.

I tried to connect this noise normal to the height and figured out that the intensity of this normal is too high which creates high values of shadows/lights in the normal output. So I tried to lower intensity with normal intensity node, it made them less visible (still visible) and also removed the randomness of sparkles reflection which I wanted to achieve in the first place.
So this knowledge of the problem doesn't help me to find the solution. Is there someone who had deal with a similar problem? Or is there another way to create this sparkles without such artifacts?

Below are a few screenshots.
Last Edit: October 13, 2018, 08:57:38 pm

even from a normal distance, these dots are still visible

These results are as expected. The different normals catch light from different angles, so some of them get lit more strongly than others depending on what they reflect.

This sounds like a flow map use case. Game engines use flow maps (sometimes called comb maps) to provide anisotropic reflection/refraction to thing like hair textures. It's similar to using a normal map, though the implementation varies a bit. The examples I've seen give a distinct sheen without producing a contrasting shadow.

I have no real personal experience with that method, so I can only point you in that general direction for your research. Good luck and let us know if you perfect a method for Substance!
David Roberson
Freelance 2D|3D Artist

Auburn CA, United States of America