@stevenpg/cesium-spatial-core

Shared machinery behind the cesium-spatial grid libraries: everything about drawing cells on a Cesium globe that does not depend on which spatial index produced them.

You usually do not install this directly — @stevenpg/cesium-h3 depends on it and re-exports the parts you need. Reach for it if you are adapting another index onto the same rendering and level-of-detail machinery.

npm install @stevenpg/cesium-spatial-core cesium

What is here

Rendering. CellPrimitiveLayer batches many cells into one Cesium Primitive, separating set changes (which rebuild geometry) from style changes (which write per-instance attributes and do not). CellEntityLayer reconciles cells against an EntityCollection, keeping surviving entities identical so selections and external references stay valid.

Picking. CellPicker resolves a batched geometry-instance pick back to a cell id by asking each registered layer to claim it.

Camera. computeViewInfo reports the visible extent plus ground meters-per-pixel, derived from the frustum rather than raw camera altitude, so oblique and horizon views stay honest.

Level of detail. selectLevel maps a ground resolution onto an index level by comparing in log space; LevelSelector adds a deadband so a nudged camera does not thrash between levels.

Geodesy. unwrapLongitudes and ringToRectangle keep antimeridian-straddling cells from producing globe-spanning bounding boxes. densifyRing subdivides along geodesics so long cell edges do not visibly cut through the globe.

Cesium is a peer dependency (>= 1.95, or @cesium/engine).

Apache-2.0.