Normal Map issue casing hard edges at texture seams - Maya 2014 > Mental Ray
polycounter lvl 12
Hey guys,
I've ran into this issue with this model at its rendering stage now, and its driving me crazy. I've found a way to get around it, and its led me to suspect that the original scene file is corrupt or broken in some way, but I can't figure out how.
Basically, this character model was created in ZBrush > retopo in Maya 2014 > Polypaint, etc > Normal maps exported from ZBrush > applied to low res model.
However, when rendering using mental ray in Maya 2014, the texture seams show up really badly, and the lighting looks very flat and odd in general. It seemed like it was a problem in the Normal maps, but as far as I can see, they seem fine. Green is facing up, red to the right, and blue; Maya's native setup.
'Maya Derivatives' is on in mental rays options. Turning it off you can see a big difference on parts of the model such as the face, but oddly again, her arms and chest don't look any different, rendering still this way.
My workaround was to copy the meshes and lights to another scene, and re-render using exactly the same settings. Doing this made the problem go away oddly enough. I decided to do this because my old development Maya files of the project also had no problem using the same Normal maps, so I thought maybe the scene causing the issue was broken somehow?
The image to the left is from the scene with a problem of some kind. The image to the right is the same meshes, same lights, same materials, but in a different scene. (The environment colour is slightly darker in the copied scene so it looks mildly darker overall). Also the renders look tatty because I stopped them as soon as they showed the whole image in mental ray, sorry :P
As for the normal map itself, the area on the arm that shows the texture seam is a texture seam on the same uv map. This shows her two arms. The geometry was mirrored as it was modelled, but Freeze Transformations was used, and Maya shows the normals all facing the right directions, etc on the mesh itself.
The arms are not mirrored in UV space, with their own two separate places on the map. This is how the maps were baked out of ZBrush too.
mia_material_x shader used for every surface in both scenes.
So is something wrong here that I am missing? Why does the same model, same materials (diff, spec, norm), and same lighting work fine in one file, and not another? Is the original file corrupt? Or have I accidentally done something silly to an option in the original file? 'Maya Derivatives' is on in both scenes, and as far as I can see, mental ray is set up the same in both scenes also.
Not knowing what has / had happened here is really bugging me!
Thanks,
- Ricky
I've ran into this issue with this model at its rendering stage now, and its driving me crazy. I've found a way to get around it, and its led me to suspect that the original scene file is corrupt or broken in some way, but I can't figure out how.
Basically, this character model was created in ZBrush > retopo in Maya 2014 > Polypaint, etc > Normal maps exported from ZBrush > applied to low res model.
However, when rendering using mental ray in Maya 2014, the texture seams show up really badly, and the lighting looks very flat and odd in general. It seemed like it was a problem in the Normal maps, but as far as I can see, they seem fine. Green is facing up, red to the right, and blue; Maya's native setup.
'Maya Derivatives' is on in mental rays options. Turning it off you can see a big difference on parts of the model such as the face, but oddly again, her arms and chest don't look any different, rendering still this way.
My workaround was to copy the meshes and lights to another scene, and re-render using exactly the same settings. Doing this made the problem go away oddly enough. I decided to do this because my old development Maya files of the project also had no problem using the same Normal maps, so I thought maybe the scene causing the issue was broken somehow?
The image to the left is from the scene with a problem of some kind. The image to the right is the same meshes, same lights, same materials, but in a different scene. (The environment colour is slightly darker in the copied scene so it looks mildly darker overall). Also the renders look tatty because I stopped them as soon as they showed the whole image in mental ray, sorry :P
As for the normal map itself, the area on the arm that shows the texture seam is a texture seam on the same uv map. This shows her two arms. The geometry was mirrored as it was modelled, but Freeze Transformations was used, and Maya shows the normals all facing the right directions, etc on the mesh itself.
The arms are not mirrored in UV space, with their own two separate places on the map. This is how the maps were baked out of ZBrush too.
mia_material_x shader used for every surface in both scenes.
So is something wrong here that I am missing? Why does the same model, same materials (diff, spec, norm), and same lighting work fine in one file, and not another? Is the original file corrupt? Or have I accidentally done something silly to an option in the original file? 'Maya Derivatives' is on in both scenes, and as far as I can see, mental ray is set up the same in both scenes also.
Not knowing what has / had happened here is really bugging me!
Thanks,
- Ricky
Replies
Says it all really doesn't it. What a tit I am. Sorry for wasting people's time who viewed this topic.