Black faces - caused by normal map

I wasn’t sure where to put this, but I finally decided this is the best spot.

I am not new to blender(since 2.43) or 3d, and I think this is the first time this has happened to me (bad memory)

I have some black faces on my model, I have found out what is causing it, a normal map. When I turn on the normal map I get the black faces (this happens on other models using other normal maps)

The normal map is image generated.

Any help is appreciated.


Black.blend (268 KB)


“Black faces” in my experience are caused by “normals facing the wrong way.” (As well you know…) Could it possibly be that the map causes the normal-vector for these pixels to “go over the edge?”

What happens to the effect that you are seeing when you increase or decrease the influence of the map? Exactly which channels of data are being modulated by the map, and to in what amounts? What is the range of +/- offset values contained in the map?

If “this happens on other models using other maps …” do you see any sort of common-thread between the various cases? (He said, grasping at straws while worrying that one day he might encounter the same :eek: himself…)

what black faces do you mean?

I opened your and could only find one side of the model in darkness from the Sun lamp you are using

is that what you mean?

i have this prob to, so it cant just be a face problam

I tested it on 2.49b and svn 2.5

and both don’t have a problem here

might be related to a graphics card problem or OS
(I’m running a Mac)

Thanks for the reply’s.


I forgot to say that you need to have GLSL enabled. The black faces dont show up on a render, but they appear blurry instead.

I have tested the gun with 4 normal maps, all have the same problem.

The black/blurry faces on happens when I unwrap Project from view, if I unwrap it in a different way this problem stops.

I tried appending the file to another blend, same problem.

Any ideas?

You’ve got interior faces. Get rid of 'm.

I have GLSL enabled and there is no problem in the 3d view
but when it renders - those sections seem to be missing the the map

I’m not sure what the problem is - but I remapped it and it worked (Project from view)

(also I only found any internal faces in the middle section - not the tip of the gun where there is another problem)

maybe try unrapping the model properly (marking seams)

may I suggest that when this happens try turning on NoVnormalFlip