dc(tree, pts)
function dc(tree, pts) {
const depth = new Int32Array(pts.length).fill(-1),
colorized = new Float32Array(pts.length).fill(NaN);
let recursion_count = 0;
function traverse(i) {
const j = tree.predecessor[i];
if (j < 0) {
colorized[i] = depth[i] = 0; // root
return;
} else if (depth[j] < 0) {
traverse(j); // recurse
recursion_count++;
}
depth[i] = depth[j] + 1;
colorized[i] =
colorized[j] +
Math.atan2(pts[i][1] - pts[j][1], pts[i][0] - pts[j][0]) / 2 ** depth[i];
}
for (let i = 0; i < colorized.length; i++) traverse(i);
return { depth, colorized, recursion_count };
}
src = "https://gist.githubusercontent.com/Fil/450db51a15fdc8bd34a12cb8a9961976/raw/680961da57d2b11a0e3e6993e5f79bd035729831"
nodes = d3.csv(`${src}/node_list.csv`, d3.autoType)
edges = d3.csv(`${src}/edge_list.csv`, d3.autoType)
nodesIndex = new Map(nodes.map((d, i) => [d.osmid, i]))
function createGraph(nodesIndex, edges) {
const graph = { sources: [], targets: [], costs: [] };
edges.forEach(({ u, v, length }) => {
const i = nodesIndex.get(u),
j = nodesIndex.get(v),
cost = length;
graph.sources.push(i);
graph.targets.push(j);
graph.costs.push(cost);
graph.sources.push(j);
graph.targets.push(i);
graph.costs.push(cost);
});
return graph;
}
graph = createGraph(nodesIndex, edges)
import { shortest_tree } from "@fil/dijkstra"
origins = Array.from({ length: 1 }, () => (Math.random() * nodes.length) | 0)
tree = shortest_tree({ graph, origins })
pts = nodes.map(d => projection([d.x, d.y]))
delaunay = d3.Delaunay.from(pts)
projection = d3.geoMercator().fitExtent([[10, 10], [width - 10, height - 10]], {
type: "MultiPoint",
coordinates: nodes.map(d => [d.x, d.y])
})
color = d3.scaleOrdinal(d3.schemeCategory10)
d3 = require("d3@5", "d3-delaunay@5")
height = width * 0.9
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