Geometry types¶

ZVF defines seven geometry types. Each type is identified by a string constant stored in the root .zattrs under "geometry_type". A single ZVF store holds exactly one geometry type; multi-type datasets require multiple stores.

Type constants¶

from zarr_vectors.constants import (
    GEOM_POINT_CLOUD,   # "point_cloud"
    GEOM_LINE,          # "line"
    GEOM_POLYLINE,      # "polyline"
    GEOM_STREAMLINE,    # "streamline"
    GEOM_GRAPH,         # "graph"
    GEOM_SKELETON,      # "skeleton"
    GEOM_MESH,          # "mesh"
)

Comparison matrix¶

Property	`point_cloud`	`line`	`polyline`	`streamline`	`graph`	`skeleton`	`mesh`
Discrete objects	—	—	✓	✓	✓	✓	✓
`links/<delta>/`	—	✓	✓	✓	✓	✓	—
`links/<delta>/`	—	—	—	—	—	—	✓
`object_index/`	—	—	✓	✓	✓	✓	✓
`cross_chunk_links/`	—	—	✓	✓	✓	✓	—
`object_attributes/`	—	—	✓	✓	✓	✓	✓
`groupings/`	—	—	✓	✓	✓	✓	✓
Per-vertex attributes	✓	✓	✓	✓	✓	✓	✓
Object sparsity	—	—	✓	✓	✓	✓	✓
Multiscale pyramid	✓	✓	✓	✓	✓	✓	✓
Draco compression	—	—	—	—	—	—	✓
`is_directed` flag	—	—	—	—	✓	—	—
`is_tree` flag	—	—	—	—	✓	✓	—

Type selection guide¶

Data description	Recommended type
Lidar, synchrotron point scan, single-molecule localisation	`point_cloud`
Pairs of connected points (short segments, contact sites)	`line`
Ordered vertex sequences without tractography metadata	`polyline`
MRI/synchrotron tractography streamlines with step size / seeding metadata	`streamline`
General connectivity graph (not necessarily a tree)	`graph`
Neuronal morphology, vascular tree (tree topology, SWC-compatible)	`skeleton`
3-D surface mesh (cell boundary, brain surface, organelle hull)	`mesh`

Per-type documentation¶