[SOLVED] Poor Normal Reproduction

Does anyone have any thoughts as to why the normal map for this model displays terrible in jME, but looks great in Blender?

Notice the wing and intake are shadowed on top for no apparent reason. This is a pic with my own shader, but it looks exactly the same in lighting.j3md.

In Blender:

I’m using a scaled down normal map in jME, but I’ve also tried using the same normal map that’s used in blender with the same results.

in the IDE there is a light source
This is the reason for the “shadow”
Use a Ambient light instead and the problem should be solve
I think it s a directional light, so under the plane it should be all black if i m right.

Else i would suggest to use a light in blender at the exact same location to troubleshoot your bug since there isn’t any light in the blender picture you sent.

There are two lights in the Blender pic, a Sun light and a Hemi. I’ve moved around the lamps in the IDE and Blender, there are no issues with the normals or lighting in Blender, everything looks great, but in the IDE it looks terrible. I didn’t take a pic, but for some reason in the IDE with the light positioned as is there’s lighting on the bottom of the engine intake, which, of course, there shouldn’t be as it’s facing away from the light, then on top of the intake there’s no lighting even though it’s facing the light.

Then there’s shadowed areas creeping up on top of the wing too even though it’s facing the lamp and should be lit.

is it possible while making the model you inverted the face and they render lighting in the wrong direction since they are compute as if they where upside-down?

try this maybe? https://forums.unrealengine.com/showthread.php?61438-Is-the-normal-map-vertical-lighting-inverted-(Possible-bug-)

Unfortunately neither of those seem to be the case. The face normals are all pointing the right direction in Blender and neither the red, green nor blue channels need be inverted.

Hmm, actually inverting the green channel does make a difference. The problem switches to the other side of the ship.

let me know if you ever get it fix! I may encounter this someday haha

Sure thing, I’m guessing it must because I used a mirror modifier in Blender so only half of the ship was baked and the other half just copied the same UV coordinates. Even with the mirror modifier applied this displays fine in Blender though.

Yea probably a blender property make it work fine, but it s probably lost during the export and you end up with this kind of bug sadly…

Lame, unfortunately giving all faces their own space on the UV layer and re-baking the normals did not make any difference.

Okay I think I got it now. I had to, obviously, re-bake the normals from the high-res model and de-invert the green channel in my shader. Thanks for all your help!

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Nice good to know! :slight_smile:

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