Normal map seams become more obvious as camera move away

Hi,

I’ve recently finished the Low Poly Character Creation Series http://cgcookie.com/blender/cgc-courses/low-poly-character-creation-blender-unity/ and have imported my character into Unity. At first, all seemed well, but I soon noticed that as the camera moved further away from my model, the normal map seams became darker and more obvious. I created another character in Blender following the exact same process and found that the issue exists there as well. I was wondering if anyone knows how to mitigate this issue… I’ve attached 2 rendered pics of the new character inside blender (using blender render). The left pic has the camera close to the character and the seams are barely visible. The right pic is further away and the seams are more obvious.


Thank you very much for your time!

The easiest way to fix this is usually to give your UV islands a larger margin so that when the character is further away from the camera you dont get the bleeding effect on your seams.

If your texture size is 2048X2048, i would use a margin of 6.
with a texture size of 1024X1024, margin of 8 or more.
with texture size 512X512 margin of 12 or more.

Hope that helps.
Polygobblerr

Hey Polygobbler, Thanks so much for your response, your suggested technique seems to have solved the issue! Many, many thanks and a thousand blessings upon your home good sir! (or madamme)

And for the sake of clarity if anyone with the same issue should read this, the Island Margin Polygobblerr is referring to is found in the Bake settings drop down and is just labeled as “Margin: #”. (Not the island margin in the Smart UV Project unwrap settings)

I can’t be 100% sure this is your problem but:
Keep in mind that normal maps don’t support alpha. That’s considered as black, which is a concave surface. That bleeds on the rest of the normals and makes your seem evident. No margin is going to help you in that case. Your model normals must have a background, just like bump maps must have a 50% neutral grey one. In short, bake your normals with no clear background.
Please let me know if this helped you solve your normals troubles!

Hey Steno,

Increasing the margin to the numbers suggested by polygobblerr worked for me. But I did try to implement your suggestion as well. Unfortunately, I’m not sure how to get the area outside the UV islands to be the neutral purple color. I’ve tried checking and unchecking the clear option under the Bake options but that didn’t seem to have any effect on the area outside the uv islands of the baked image. The only other way I can think of doing it would be to manually set the color when first creating the image to bake to. Was there some other way that you were thinking of?

Thanks for your help!

If you baked out the texture with an alpha channel, you could use an external program to fill the background in with a neutral purple(R:128,B:128:G:255). You could use gimp or photoshop to do this.