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ZarrCubeVelocityProvider

Provider responsible for loading and rendering 3D velocity fields (U and V components) from Zarr datasets as animated Cesium WindLayers.

Remarks​

This provider targets the NOC-OI fork of cesium-wind-layer v0.11.0. The fork adds bounded camera-driven particle scaling through minVisibleRatio and restores overview styling after zooming back out. The provider loads 3D vector data, slices it by elevation, and creates animated particle layers that visualize flow direction and speed.

Example​

const provider = new ZarrCubeVelocityProvider(viewer, {
  urls: { u: 'uo.zarr', v: 'vo.zarr' },
  variables: { u: 'uo', v: 'vo' },
  bounds: { west: -10, south: 30, east: 10, north: 45 }
});
await provider.load();

Accessors​

queryIndexOffsets​

Get Signature​

get queryIndexOffsets(): Record<string, number>;

Global coordinate offsets represented by index zero of the in-memory subset.

Returns​

Record<string, number>

Elevation offset used by shared profile query helpers.

Constructors​

Constructor​

new ZarrCubeVelocityProvider(viewer, options): ZarrCubeVelocityProvider;

Creates a new ZarrCubeVelocityProvider instance.

Parameters​

ParameterTypeDescription
viewerCesiumHostCesium viewer or widget where the layers will be rendered.
optionsVelocityOptionsVelocity dataset options (see VelocityOptions).

Returns​

ZarrCubeVelocityProvider

Throws​

If either U or V has neither a URL nor a custom store.

Methods​

destroy()​

destroy(): void;

Removes all active wind layers from the Cesium scene.

Returns​

void

Remarks​

Loaded U/V arrays and selectors remain in memory. Call updateSlices or load to render layers again.

getTimeSeries()​

getTimeSeries(
   position, 
   selectors?, 
options?): Promise<QueryResult>;

Queries all time values and vector components at one position.

Parameters​

ParameterTypeDescription
positionQueryPosition[longitude, latitude] in WGS84 degrees.
selectors?ZarrSelectorsFixed selectors for dimensions other than time.
options?QueryOptionsQuery cancellation and coordinate-output controls.

Returns​

Promise<QueryResult>

Speed and component values ordered by time.

getVerticalProfile()​

getVerticalProfile(
   position, 
   selectors?, 
options?): Promise<QueryResult>;

Queries all loaded elevation values and vector components at one position.

Parameters​

ParameterTypeDescription
positionQueryPosition[longitude, latitude] in WGS84 degrees.
selectors?ZarrSelectorsFixed selectors for dimensions other than elevation.
options?QueryOptionsQuery cancellation and coordinate-output controls.

Returns​

Promise<QueryResult>

Speed and component values ordered by elevation.

load()​

load(): Promise<void>;

Loads both U and V components of the velocity field from their respective Zarr datasets.

Returns​

Promise<void>

A promise resolved after both components, coordinates, selected subsets, and all elevation wind layers have loaded.

Throws​

When either custom or URL-backed store, selected array, dimensions, or data chunks cannot be read.

Remarks​

U and V are loaded concurrently and must describe compatible grids.

queryData()​

queryData(
   geometry, 
   selectors, 
options): Promise<VelocityQueryResult>;

Queries velocity components and derived speed at a WGS84 point.

Parameters​

ParameterTypeDescription
geometryQueryGeometryPoint geometry in [longitude, latitude] degrees.
selectorsZarrSelectorsOptional time/elevation selectors for this query.
optionsQueryOptionsCancellation and coordinate-output controls.

Returns​

Promise<VelocityQueryResult>

Speed values plus aligned U and V component arrays.

Throws​

For unsupported geometries, invalid selectors, or failed reads.

Remarks​

A ranged elevation selector returns a vertical profile; a ranged time selector reads the source arrays instead of only the rendered layers.

updateSelectors()​

updateSelectors(options): Promise<void>;

Updates the dimension selectors, multiscale level, or geographic bounds, and reloads the velocity data accordingly.

Parameters​

ParameterTypeDescription
options{ bounds?: BoundsProps; multiscaleLevel?: number; selectors?: { [key: string]: ZarrSelectorsProps; }; }Partial data-selection update. Changed selectors, level, or bounds destroy the existing wind layers and reload both components.
options.bounds?BoundsProps-
options.multiscaleLevel?number-
options.selectors?{ [key: string]: ZarrSelectorsProps; }-

Returns​

Promise<void>

A promise that resolves after the change is scheduled. If no value changed, it resolves without rebuilding layers.

Remarks​

Latitude bounds are clamped to the Web Mercator limit.

updateSlices()​

updateSlices(options): Promise<void>;

Updates the rendered slices (number of vertical layers) based on the spacing or exaggeration.

Parameters​

ParameterTypeDescription
options{ belowSeaLevel?: boolean; sliceSpacing?: number; verticalExaggeration?: number; }Partial slice-layout update. sliceSpacing is an elevation index interval; verticalExaggeration scales height; belowSeaLevel controls whether depth is placed beneath the ellipsoid.
options.belowSeaLevel?boolean-
options.sliceSpacing?number-
options.verticalExaggeration?number-

Returns​

Promise<void>

A promise resolved after replacement wind layers are created.

Remarks​

Non-positive spacing/exaggeration and spacing beyond the elevation dimension are rejected with a warning.

updateStyle()​

updateStyle(options): void;

Updates the visual style of the velocity layers, such as opacity, color scale, or particle simulation parameters.

Parameters​

ParameterTypeDescription
options{ colormap?: string; opacity?: number; scale?: [number, number]; windOptions?: VelocityWindOptions; }Partial style update. windOptions are forwarded to each WindLayer except particleHeight, which remains derived from Zarr elevation.
options.colormap?string-
options.opacity?number-
options.scale?[number, number]-
options.windOptions?VelocityWindOptions-

Returns​

void

Remarks​

Existing layers are updated in place; source data is not reloaded.

Properties​

bounds​

bounds: BoundsProps;

Configuration defining the geographic bounds of the cube.

cubeDimensions​

cubeDimensions: [number, number, number] | null = null;

Cube dimensions: [longitude, latitude, elevation].

dimensionValues​

dimensionValues: object = {};

Dimension coordinate arrays (e.g. lat, lon, elevation).

Index Signature​

[key: string]: string[] | number[] | Float64Array<ArrayBufferLike>

elevationShape​

elevationShape: number = 0;

Shape (size) of the elevation dimension.

id​

id: string = '';

Unique identifier for the cube provider instance.

levelInfos​

levelInfos: string[] = [];

Information about multiscale levels in the Zarr dataset.

multiscaleLevel​

multiscaleLevel: number = 0;

Current multiscale level to load.

selectors​

selectors: object;

User-defined selectors for slicing dimensions.

Index Signature​

[key: string]: ZarrSelectorsProps