I am looking for help with this render. It is very early on in the texturing process and I have experienced this issue with my normal maps every time I render with PBR. I don't know why but it seems like whenever I attach a normal map onto an object, that object suddenly ignores lights in the scene and does a very flat default look. The other objects in the scene render properly. Only one light is in the scene.

This has happened before with other objects in other houdini files. Not sure why it just goes flat… I'll admit when I render with MPR (MicroPolygon Rendering the same thing occurs, so I am confident it is within my shader). Any help would be appreciated.

See image for refrence.

~ Garrett Hoyos
BYU ANIMATION

Hi Garrett,

Are you using the Mantra Surface shader? Are you using Tangent Space normal maps from Zbrush or 3D Coat or Mudbox? What version of Houdini are you using?

Cheers,

Peter B

I am using an uber shader very similar to the mantra surface shader that my buddy Ethan created for our film we are making. He interned at SideFX this past summer so I assumed that was okay, but maybe I should open up the VOP, though I'm not really sure what to look for to see if it's wrong. It pretty much looks identical to the mantra SS.

My normal map is exported as Object Space Normals from Mudbox. I am using Houdini Master 12.0.

Thanks
~Garrett

Well after a couple hours of tweaking things I realized it wasn't in the shader at all. Apparently houdini doesn't like it when the shadows are turned off in the area light settings. Normal objects render fine with no shadows but as soon as a normal map is applied everything goes flat.

Thanks for the help to find my answer. You got me thinking of solutions.

Garrett
BYU ANIMATION

No worries Just FYI, in general Tangent Space normal maps are the standard, but unfortunately SESI's Mantra Surface doesn't natively support them. I had suspected that might be the issue, I never would have guessed (without seeing the file) about the shadows problem!!

Glad it's up and running!

Cheers,

Peter B