O-Voxel is the native structured representation used by TRELLIS.2 to encode geometry and surface attributes without relying on an iso-surface field.

Structure
Sparse voxels
Field
Field-free
Carries
Geometry + surface attributes
Used by
TRELLIS.2

Why field-free matters

Iso-surface representations usually recover a boundary from a scalar field. O-Voxel represents the asset without requiring that conversion, which broadens the topology it can express.

Representation is not topology cleanup

Support for open or non-manifold geometry is useful for generation, but a downstream task may still require a closed manifold, retopology, or a lower triangle budget.