Issue with normal lighting

[Niosop]

When lighting normal mapped objects something is wrong. This is using the default diffuse bumpmap shader, tested in 2.3 and 2.31.

 

Notice that the lit side of the bumps changes as the cube rotates. This makes them look like bumps sometimes and holes at other times.

 

The camera is at roughly the same location as the light. The light you see in the background is an ambient light.

 

The same model and normal map in Unity doesn't exhibit this problem.

 

Demonstration:

 

http://vimeo.com/9433786

 

Anyone have any ideas?

[Niosop]

Just a bump to make sure Josh sees this

[Josh]

Looks like the X and Y axes of the normal are swapped.

[BrokenPillar]

I updated the files with the X and Y swapped in SwizzleTest.zip on the other thread (http://leadwerks.com/werkspace/index.php?/topic/1172-dxt5nm-and-3dc-dds-compression/page__st__20). It seems to fix the problem.

 

This topic has always caused me grief in the past since it varies with each engine (which might explain why the normal looked correct in Unity) and with different software apps you use to bake normals.

[Canardia]

I remember moose saying that you need to invert the green color (Y axis) in the normal map.

[Niosop]

I remember moose saying that you need to invert the green color (Y axis) in the normal map.

 

That did it! Thanks Loomja, I was pulling my hair out trying different combinations, swizzling, etc.

[Kazar]

I remember moose saying that you need to invert the green color (Y axis) in the normal map.

 

Does this mean I need to invert the Y every time I make normal maps for LE? (in photoshop with Nvidia plugin in my case)

 

Edit: I did some tests and yeah.. seems like I've got to redo all my normal maps I didn't spot this fact anywhere in the wiki.

[Josh]

I think there's an option in most exporters because some people use upside down normal maps. Ours are the correct way.

[Kazar]

I think there's an option in most exporters because some people use upside down normal maps. Ours are the correct way.

 

While it may be so I think this should be mentioned somewhere in the wiki.

[Niosop]

DX uses +Y, OpenGL uses -Y. If you have a lot of things already done +Y, then you can modify the shader to invert the Y instead of redoing your normal maps.

[Kazar]

DX uses +Y, OpenGL uses -Y. If you have a lot of things already done +Y, then you can modify the shader to invert the Y instead of redoing your normal maps.

 

My project is only week old right now so I've already remade all my normal maps