Getting a weird artifact on the Iray render

Synthdrive

Hi everybody, first post here!

This past month I've been trying to learn game props texturing, I think I'm at a good point, but some weird glitch on Substance Painter Iray renderer is driving me crazy.

In the first screenshot, you can see how the model looks on the "Painting Mode", while the second screenshot is from the "Rendering Mode". The model shows correctly in the first one, with the AO map showing black on that square hole. But when I try to render it, it shows brown! It's like the AO map is not working in the Rendering mode. I've tried everything, checked the materials, dust and dirt in cavities and so on, but nothing works... Any idea of where the problem might be ? Thanks...

Fabi_G

Unrelated to this specific issue, but if this is a game prop, I would also present (and preview) it rendered in real-time (Unreal, Unity, ...).

Eric Chadwick

One potential clue… a path tracer like iray never uses a prebaked ambient occlusion texture. Instead they calculate occlusion dynamically.

It looks like that groove is very shallow, so it would not occlude light rays as dramatically as in your ao texture.

Synthdrive

Eric Chadwick said:

One potential clue… a path tracer like iray never uses a prebaked ambient occlusion texture. Instead they calculate occlusion dynamically.

You're right! It uses a prebaked AO texture. And that hole has no geometry (i wanted to save some on a trivial detail), it's just flat surface. At this point i think i'll just paint black shadows there, the holes are supposed to be very deep with no light coming through anyway.

Fabi_G said:

Unrelated to this specific issue, but if this is a game prop, I would also present (and preview) it rendered in real-time (Unreal, Unity, ...).

In Unreal it renders it the same as SP, and with washed up colors too! ;-(

Synthdrive

I've saved the pngs as 8 bits and that helped with Unreal, but the colors are still washed up. I get one thing on SP and another thing on UE. The shadows for the deep holes I've just painted them.

Fabi_G

What does it look like in Unreal? Some difference is to be expected, unless you matched your lighting in Painter with the one in your preview scene in Unreal (could search for something like "substance painter unreal lighting"). In Unreal you have to ensure the textures are setup correctly: sRgb disabled for ORM map (or Ao, Roughness and Metallic if not packed) and DirectX Normal map.

Synthdrive

Fabi_G said:

What does it look like in Unreal? Some difference is to be expected, unless you matched your lighting in Painter with the one in your preview scene in Unreal (could search for something like "substance painter unreal lighting"). In Unreal you have to ensure the textures are setup correctly: sRgb disabled for ORM map (or Ao, Roughness and Metallic if not packed) and DirectX Normal map.

Thanks, fixed!