blender export with normal map warning and errors

I use a makehuman model. When I export it, I got some warnings about the normal map:
Blender Texture Bump is mapped to normals, but it’s not flagged as a normal map.

What does it mean and how to fix it ?

In the egg file, I find some vertex with:
{ -1.#IND00 -1.#IND00 -1.#IND00 }
{ 1.#QNAN0 1.#QNAN0 1.#QNAN0 }
It causes a problem and pview can’t load the model.

How can I fix this issue in blender ?

Thank you.

if you press “F6” in blender(to get to the texture-panel) you can enable/disable certain buttons. such as mipmapping,tilingmode,filtering etc. one of them is called “normalmap” just tick it :slight_smile:

thought i dunno where those messi tangent and binormals came from.

Also make sure the normal map is in tangent space mode, and is actually a tangenjt space normal map, as that is all that is supported.

Bad tangents/binormals like that are caused by degenerate faces or degenerate uv mapping on faces. i.e. if a face has 2 or more vertices at exactly the same point or the uv map has texture coordinates at exactly the same point for different vertices. I’m afraid I know of no easy way to track such things down, though screwy uv coordinates will tend to produce a screwy rendering when you visualise in Blender - look out for faces that are constant colour or ‘stripy’.

I have to make another account as my original account cannot post on this thread due to the forum problem.

Thank you. ThomasEgi’s suggestion fix the warning.

The location near the “ear” of the UV map does have quite a number of texture coordinates at exactly the same point. But this model is quite complicated, it seems not easy to fix it as I am not familiar with modeling.

What can I do to fix it ? Can a high resolution UV map help to fix it ? Any short cuts ?

If I don’t have tangents and binormals, does it mean that I can’t use the autoshader for normal map function and no other features lost ?

Just had to do exactly the same as you… my account also won’t let me access this thread. Grrrr.

No easy fix I’m afraid, though I could potentially change the code to detect when it goes screwy and put in an arbitrary direction and give a warning - I’ll add that to my todo list, though that is quite long right now so don’t expect it fast. And yes, all you will lose is normal mapping, at least as far as the shader generator goes - you can also need this information for your own custom shaders, but thats it.

You could apply google to the problem - someone might have written a Blender script for fixing such issues, but its a bit of a long shot. Only real fix is to get your hands messy and start editing.