Minimal structural shape of a scene-graph node for the visibility walk.
THREE.Object3D satisfies it structurally (visible: boolean,
parent: Object3D | null), and so do the deliberately-minimal mock shapes
used by the LOD modules (which never import THREE for this).
Both members are optional so a partial shape stays usable: a missing
visible counts as visible (only an explicit false hides), and a missing
parent ends the walk.
Minimal structural shape of a scene-graph node for the visibility walk.
THREE.Object3Dsatisfies it structurally (visible: boolean,parent: Object3D | null), and so do the deliberately-minimal mock shapes used by the LOD modules (which never import THREE for this).Both members are optional so a partial shape stays usable: a missing
visiblecounts as visible (only an explicitfalsehides), and a missingparentends the walk.