Are the 64*64*64 and 128*128*128 voxel models solid or surface only?

[fomalhautb]

In the Pix2Vox++, there are results for resolution other than 32 * 32 * 32, which is preprocessed by 3D-R2N2 and is surface only. Pix2Vox++ has achieved a higher score on higher resolution. I think this only makes sense if the higher resolution models are solid models because the surface models are harder to hit and have a lower IoU while the resolution increases. Are the 64 * 64 * 64 and 128 * 128 * 128 voxel models solid?

[fomalhautb]

I realized that the voxels preprocessed by 3D-R2N2 are actually solid. So I think the higher resolution models should also be solid.