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VectorLayer

VectorLayer renders wind barbs as icons with adaptive sampling based on zoom and viewport.

Data Contract

The layer accepts lonlatGrid as point geometry and samples vectors from dataDir and dataMag.

Supported lonlatGrid layouts:

  1. Flattened structured grid (preferred for quadkey mode):

    • lonlatGrid: 1D array of [lon, lat]
    • shape: [rows, cols]
    • dataDir: 1D array of direction values (degrees)
    • dataMag: 1D array of magnitude/speed values

  2. Flattened point list (unstructured/spherical sampling):

    • lonlatGrid: 1D array of [lon, lat]
    • dataDir: 1D array of direction values (degrees)
    • dataMag: 1D array of magnitude/speed values
    • shape is optional and only used by the quadkey fast path.

For all modes, arrays are expected in index-aligned order (lonlatGrid[i], dataDir[i], dataMag[i]).

VectorLayer Props

In addition to inherited CompositeLayer/IconLayer props, VectorLayer supports:

Prop Type Required Default Notes
lonlatGrid Array<[number, number]> Yes None Point geometry used for barb placement.
dataDir ArrayLike<number> Yes None Direction in degrees, aligned to lonlatGrid index.
dataMag ArrayLike<number> Yes None Magnitude/speed, aligned to lonlatGrid index.
shape [number, number] | null Conditional null Required for structured quadkey fast sampling ([rows, cols]). Optional otherwise.
triangulationMode 'quadkey' | 'unstructured' No 'quadkey' Sampling strategy. quadkey uses grid-based stepping when shape is provided.
sizeScale number No 25 Base icon scale. Effective scale also depends on zoom.
spacingScale number No 1 Multiplier for symbol spacing. Larger values create sparser barbs.
elevation number No 0 Z coordinate for placed symbols.
angleOffset number No 0 Extra rotation offset (commonly 180 for globe orientation).
billboard boolean No false Forwarded to icon rendering behavior.
getColor Accessor<Color> No `(x) => x.color
getLabel Accessor<string> No (x) => x.label Label accessor (if used by consumers).
getWeight Accessor<number> No `(x) => x.weight
getPosition Accessor<[number, number, number?]> No (x) => x.position Position accessor override.
parameters object No { depthCompare: 'always', cullMode: 'front' } GPU render-state overrides.
id string No deck.gl generated layer id Standard layer id override.

Requirement rules:

  1. lonlatGrid, dataDir, and dataMag are required.
  2. If using structured quadkey sampling, provide shape as [rows, cols].
  3. For structured grids, rows * cols should match the length of lonlatGrid, dataDir, and dataMag.

Notes

  • Directions are converted to icon angle with -direction + 180 + angleOffset.
  • Magnitudes are bucketed in 5-unit increments for barb icon selection.
  • quadkey mode with shape uses viewport-aware grid stepping for performance.
  • unstructured currently use projected screen-space decimation.
  • Invalid/non-finite coordinates or vector values are skipped during rendering.
  • The internal icon sublayer is rendered with pickable: false.