shore.io.boxes

The Box data class — one Xall cc.par type-9 marker box — plus JSON serialisation helpers. Used by shore.io.cc_par.write_cc_par(boxes=...) and the shore cc-par --boxes CLI.

For the cc.par boxes section format, the algorithm that generates boxes from an STL, and the ParaView visualiser, see Marker boxes.

Box

@dataclass(frozen=True)
class Box:
    vertices:          np.ndarray      # (8, 3) float64
    associated_block:  str

One type-9 hexahedron with 8 corner vertices in the canonical "i-fastest" Fortran-column-major order:

Index	(i, j, k)
0 (v1)	(lo, lo, lo)
1 (v2)	(hi, lo, lo)
2 (v3)	(lo, hi, lo)
3 (v4)	(hi, hi, lo)
4 (v5)	(lo, lo, hi)
5 (v6)	(hi, lo, hi)
6 (v7)	(lo, hi, hi)
7 (v8)	(hi, hi, hi)

The (i, j, k) directions need not be world-aligned — any rotated or sheared parallelepiped is a valid Box as long as the corner correspondence above is preserved.

Box.__post_init__ validates the hexahedron at construction: non-finite values, wrong shape, empty associated_block, degenerate / coplanar / self-intersecting (bow-tie) / inverted geometry all raise ParameterError.

associated_block is a SHORE block label; at write time the cc.par writer resolves it to a 1-based index into the blocks list. The box then inherits the block's level / group / priority for chimera precedence.

Box.from_aabb

@classmethod
def from_aabb(
    cls,
    vmin: tuple[float, float, float] | np.ndarray,
    vmax: tuple[float, float, float] | np.ndarray,
    associated_block: str,
) -> Box

Convenience constructor for an axis-aligned Box. Builds the 8 canonical-order vertices from the two diagonal corners of an AABB.

from shore.io.boxes import Box

box = Box.from_aabb(
    vmin=(-0.6, -0.6, -0.6),
    vmax=(+0.6, +0.6, +0.6),
    associated_block="sub0",
)

JSON helpers

def box_to_json(box: Box) -> dict[str, Any]
def box_from_json(payload: dict[str, Any]) -> Box

Round-trip a Box through the JSON schema that shore cc-par --boxes consumes:

{
  "associated_block": "sub0",
  "vertices": [[-0.6, -0.6, -0.6], [+0.6, -0.6, -0.6], ...]
}

Lists of boxes are written as a JSON array of these objects; that is the exact format shore boxes-from-stl emits.

See also

• Marker boxes — full reference (algorithm, CLI, ParaView).
• shore.boxes — boxes_from_stl (STL → list of Box).
• shore.io.cc_par — write_cc_par(boxes=...).
• Algorithm — marker boxes — voxel-fill + greedy-merge derivation.