Is there a way to convert a obj into a Vectron

[spartan00j]

Hi I'm looking for a way to use the Vectron features on a obj model? Or any other 3D model. Or even possibly an animated model that I brought into octane Standalone.

Thanks

[jobigoud]

You can use a "Mesh volume SDF" node to convert an OBJ to a signed distance field. Then you can combine this with vectron primitives or other SDF objects with the union/subtraction/ink, etc. operators.

[spartan00j]

You can use a "Mesh volume SDF" node to convert an OBJ to a signed distance field. Then you can combine this with vectron primitives or other SDF objects with the union/subtraction/ink, etc. operators.

Hi I think I got it. It seems it might have been the original model I was trying to use.
Does this process requires the OBJ model to have certain qualifications. Does it need to be a watertight model?

Thanks

[jobigoud]

Yes the source OBJ makes a difference. Because it will try to figure out what is the interior vs exterior of the model. If it's not an enclosed shape it can break the ray marching. You might see massive see-through artifacts when looking at the surface. Normally when the ray marching goes slightly beyond the surface it should get a negative "distance" so it will converge back to find the surface, but if it's a positive distance on both sides of a razor thin surface it can't converge. If you convert a simple quad mesh for example there is no meaningful interior to it.

What you can do to prevent this is add an "Offset" or a "Vectron displacement" node right after the Mesh volume SDF. This will give a little bit of thickness to the reconstructed surface and should remove the artifacts.

[spartan00j]

Yes the source OBJ makes a difference. Because it will try to figure out what is the interior vs exterior of the model. If it's not an enclosed shape it can break the ray marching. You might see massive see-through artifacts when looking at the surface. Normally when the ray marching goes slightly beyond the surface it should get a negative "distance" so it will converge back to find the surface, but if it's a positive distance on both sides of a razor thin surface it can't converge. If you convert a simple quad mesh for example there is no meaningful interior to it.

What you can do to prevent this is add an "Offset" or a "Vectron displacement" node right after the Mesh volume SDF. This will give a little bit of thickness to the reconstructed surface and should remove the artifacts.

Okay thanks. One last question. Where do I apply the texture. I have a obj sequence. I'm trying to apply a brick texture with displacement. But it doesn't seem to be working.
All I see is one solid color. I tried to adjust the UV transform. But all I see is just once all it color. Thanks

[jobigoud]

I don't think that conversion retains the UVs at this point unfortunately.

[spartan00j]

I don't think that conversion retains the UVs at this point unfortunately.

Okay, I understand. But I tried to apply noise to the model. For displacement. And it gives me nothing.

[jobigoud]

Yeah it works with the original mesh polygons, not the displaced ones. You might try to use a Vectron displacement and put a noise in its Texture field. It will use the linear projection (XYZ -> UVW) though, not the Mesh UVs.