Grid artifacts on inner mesh surface

[rfeinman]

Thanks for the great model release!

I noticed that the inner surface of the generated mesh often has grid artifacts (see below image). Interestingly, this does not seem to happen on the outer surface. Do you know why that happens, and how I might fix it?

[Linyou]

We’re planning to release a tool to fix this issue in the coming days.

[Linyou]

Hi @rfeinman,

The voxel artifacts happen because we only supervise the VAE with SDF loss on the object’s surface. Everywhere else in the 3D space, we just set the SDF to a constant +1, and then normalize everything to [-1, +1]. That ends up creating a sharp jump from -1 to +1 around the surface and inside the object, which causes those voxel-looking artifacts when we run marching cubes.

[shuangw98]

Hi @rfeinman, we released a refiner to correct the sign of the SDF, thereby removing grid artifacts inside the mesh. You can give it a try.

[rfeinman]

Thanks @shuangw98 @Linyou for the release. It is an improvement, although there are still grid artifacts in a number of cases (see below). Moreover, the mesh normals appear to be flipped now in some places (leading to "invisible" surfaces in normal viewer).

Screen.Recording.2025-06-16.at.7.52.51.AM.mov

The floodfill fix from my PR seems to work a bit more reliably, so I will use that for now.