Green and red color on my baked normal map appearing

Question

Hi, it is me again. This time, I am having an issue with normal map baking. I have random red and green on my normal map that which are creating strange white shapes on my model. I tried a lot of things like playing with the ray distance and margin. I also make sure that my high poly model is not overlapping my low poly model. Now, I am stuck with this, do you have any idea?

By the way, I am doing this character for a video game, is normal map baking on low poly character the better method or should I do it an other way?

Thank you!

Answer 1

Sometimes the ray distance might not work and will create errors like these. I had the same problem where I will adjust the ray distance and I'll still get these red and green errors. So when this happens, there is the cage method.

1. Duplicate the low poly mesh and make sure it overlaps the low poly and high poly model and rename it "Cage".

2. With the Cage selected, go into Edit Mode and face selection mode. Press A to select all of the faces.

3. Press Alt + S to scale it in the normals. Make sure to hold down Shift so to scale it slowly. Scale it so it encapsulates the entire high poly mesh.

4. Now, depending on your model, you may have to go into Edit Mode with the cage object so that no detail in the high poly is poking through the cage.

   Example: In this image you can see a part of the high poly poking through the cage. So edit the cage so that it covers it entirely. From this:

To this:

5. Now go to the Bake panel, click the check box next to Cage and select your cage object.

6. Bake and see if the green red errors disappear. You may have to edit your cage object again to cover up certain areas the high poly model. Keep editing and baking until your normal map is error free!