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DelaunayInterpolation

DelaunayInterpolation samples or rasterizes the station-interpolated vector field used by the wind showcase layers. It replaces the original showcase's off-screen WebGL transform with a backend-independent implementation suitable for WebGL, WebGPU, preprocessing, and Node.js.

import {
  createWindField,
  DelaunayInterpolation,
  parseWindData
} from '@deck.gl-community/geo-layers';

const stations = await fetch('/stations.json').then(response => response.json());
const weather = await fetch('/weather.bin').then(response => response.arrayBuffer());
const field = createWindField(stations, parseWindData(weather, stations.length));

const interpolation = new DelaunayInterpolation({field, width: 256});
const sample = interpolation.sample([-97, 38], 12.5);
const raster = interpolation.rasterize(12.5);

sample returns direction in radians, wind speed, temperature, elevation, and an east/north velocity vector. Points outside the triangulated station coverage return null.

rasterize returns {width, height, data}, where data is a Float32Array containing direction, speed, temperature, and elevation in RGBA component order.

  • parseWindData(buffer, stationCount, frameCount?): Decodes the original station-major binary forecast. The default forecast length is 72 hourly frames.
  • getWindBounds(stations): Converts positive-west legacy station longitudes into geographic bounds.
  • triangulateWindStations(stations): Builds a Delaunay triangulation without external triangulation dependencies.
  • createWindField(stations, frames, options?): Creates a spatially indexed, time-varying wind field shared by all three layers.
  • sampleWindField(field, position, time?): Samples a field without constructing an interpolation wrapper.