Tricontour labelsTricontoursHexagotriangulationSpherical contoursManhattan Voronoi IIGraph VoronoiH3 odditiesH3 hexagons & geoContoursTricontour iteratorVolcano TricontoursBlurry contoursSpherical contours iteratorSpherical contours as a gradientReusing a Tricontour triangulationModified Shepard’s method II (with geoContour)MapfillSpherical isobandsPlanar tricontours on geo data (bad!)Tricontour flowerUK TricontoursTricontour isobands
d3-hexbin & tricontours heatmap
chart = {
const context = DOM.context2d(width, height),
path = d3.geoPath().context(context);
hexbin.context(context);
for (const c of contours) {
context.beginPath();
path(c);
context.fillStyle = color(c.value);
context.fill();
}
context.beginPath();
hexbin.mesh();
context.strokeStyle = "#000";
context.lineWidth = 0.125;
context.stroke();
context.beginPath();
for (const p of data) hexbin.hexagon(1, p);
context.fillStyle = "#444";
context.fill();
return context.canvas;
}
// Add all the hexagons’ to the data points, so that empty hexagons still appear in the bins
bins = hexbin(data.concat(hexbin.centers()))
contours = d3.tricontour()
.x(d => d.x)
.y(d => d.y)
.value(d => Math.sqrt(d.length - 1))
.thresholds(20)(bins)
color = d3.scaleSequential(d3.interpolateGreens)
.domain(d3.extent(contours, d => d.value))
data = Array.from({ length: (width / 10) ** 2 }, () => [
width / 2 + width * d3.randomNormal(0, 1 / 6)(),
height / 2 + width * d3.randomNormal(0, 1 / 6)()
])
hexbin = d3.hexbin()
.radius(18)
.size([width, height])
height = (width * 0.7) | 0
// Another loading strategy, maybe? (Just trying things out)
d3 = Promise.all([
import("https://esm.sh/d3@7"),
import("https://esm.sh/d3-tricontour@1"),
// https://github.com/d3/d3-hexbin/pull/19
import("https://esm.sh/gh/d3/d3-hexbin@817c015e0070a512cf0b6e40a36cc1208ba7ae96")
]).then((imports) => Object.assign({}, ...imports))
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