map = {
const [ width, height ] = dims;
const context = DOM.context2d(width, height);
const path = d3.geoPath(projection, context);
context.save();
// context.beginPath(), path(outline), context.clip(), context.fillStyle = "#fff", context.fillRect(0, 0, width, height);
// context.beginPath(), path(graticule), context.strokeStyle = "#ccc", context.stroke();
context.beginPath(), path(land), context.fillStyle = "#000", context.fill();
context.restore();
// context.beginPath(), path(outline), context.strokeStyle = "#000", context.stroke();
const canvas = context.canvas;
canvas.style.maxWidth = "100%";
return canvas;
}
dims = [ width * 4, height ];
height = {
const [[x0, y0], [x1, y1]] = d3.geoPath(projection.fitWidth(width * 4, outline)).bounds(outline);
const dy = Math.ceil(y1 - y0), l = Math.min(Math.ceil(x1 - x0), dy);
projection.scale(projection.scale() * (l - 1) / l).precision(0.2);
return dy;
}
outline = ({type: "Sphere"})
graticule = d3.geoGraticule10()
land = topojson.feature(world, world.objects.land)
world = FileAttachment("land-50m.json").json()
topojson = require("topojson-client@3")
d3 = require("d3-geo@3", "d3-geo-projection@4")
import {projectionInput} from "@d3/projection-comparison"
Purpose-built for displays of data
Observable is your go-to platform for exploring data and creating expressive data visualizations. Use reactive JavaScript notebooks for prototyping and a collaborative canvas for visual data exploration and dashboard creation.
