Published
Edited
Mar 7, 2020
Importers
3 stars
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md`# Radial TreeDiagrams

This chart shows relationships among classes in a software hierarchy. Each directed edge, going from <b style="color: ${color(0.1)};">source</b> to <b style="color: ${color(0.9)};">target</b>, corresponds to an import.
`
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chart = {
const root = tree(bilink(d3.hierarchy(data)
.sort((a, b) => d3.ascending(a.height, b.height) || d3.ascending(a.data.name, b.data.name))));

const svg = d3.create("svg")
.attr("viewBox", [-width / 2, -width / 2, width, width]);

const node = svg.append("g")
.attr("font-family", "sans-serif")
.attr("font-size", 10)
.selectAll("g")
.data(root.leaves())
.join("g")
.attr("transform", d => `rotate(${d.x * 180 / Math.PI - 90}) translate(${d.y},0)`)
.append("text")
.attr("dy", "0.31em")
.attr("x", d => d.x < Math.PI ? 6 : -6)
.attr("text-anchor", d => d.x < Math.PI ? "start" : "end")
.attr("transform", d => d.x >= Math.PI ? "rotate(180)" : null)
.text(d => d.data.name)
.call(text => text.append("title").text(d => `${id(d)}
${d.outgoing.length} outgoing
${d.incoming.length} incoming`));

svg.append("g")
.attr("fill", "none")
.selectAll("path")
.data(d3.transpose(root.leaves()
.flatMap(leaf => leaf.outgoing.map(path))
.map(path => Array.from(path.split(k)))))
.join("path")
.style("mix-blend-mode", "darken")
.attr("stroke", (d, i) => color(d3.easeQuad(i / ((1 << k) - 1))))
.attr("d", d => d.join(""));

return svg.node();
}
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data = hierarchy(await FileAttachment("flare.json").json())
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function hierarchy(data, delimiter = ".") {
let root;
const map = new Map;
data.forEach(function find(data) {
const {name} = data;
if (map.has(name)) return map.get(name);
const i = name.lastIndexOf(delimiter);
map.set(name, data);
if (i >= 0) {
find({name: name.substring(0, i), children: []}).children.push(data);
data.name = name.substring(i + 1);
} else {
root = data;
}
return data;
});
return root;
}
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function id(node) {
return `${node.parent ? id(node.parent) + "." : ""}${node.data.name}`;
}
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function path([source, target]) {
const p = new Path;
line.context(p)(source.path(target));
return p;
}
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class Path {
constructor(_) {
this._ = _;
this._m = undefined;
}
moveTo(x, y) {
this._ = [];
this._m = [x, y];
}
lineTo(x, y) {
this._.push(new Line(this._m, this._m = [x, y]));
}
bezierCurveTo(ax, ay, bx, by, x, y) {
this._.push(new BezierCurve(this._m, [ax, ay], [bx, by], this._m = [x, y]));
}
*split(k = 0) {
const n = this._.length;
const i = Math.floor(n / 2);
const j = Math.ceil(n / 2);
const a = new Path(this._.slice(0, i));
const b = new Path(this._.slice(j));
if (i !== j) {
const [ab, ba] = this._[i].split();
a._.push(ab);
b._.unshift(ba);
}
if (k > 1) {
yield* a.split(k - 1);
yield* b.split(k - 1);
} else {
yield a;
yield b;
}
}
toString() {
return this._.join("");
}
}
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class Line {
constructor(a, b) {
this.a = a;
this.b = b;
}
split() {
const {a, b} = this;
const m = [(a[0] + b[0]) / 2, (a[1] + b[1]) / 2];
return [new Line(a, m), new Line(m, b)];
}
toString() {
return `M${this.a}L${this.b}`;
}
}
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BezierCurve = {
const l1 = [4 / 8, 4 / 8, 0 / 8, 0 / 8];
const l2 = [2 / 8, 4 / 8, 2 / 8, 0 / 8];
const l3 = [1 / 8, 3 / 8, 3 / 8, 1 / 8];
const r1 = [0 / 8, 2 / 8, 4 / 8, 2 / 8];
const r2 = [0 / 8, 0 / 8, 4 / 8, 4 / 8];

function dot([ka, kb, kc, kd], {a, b, c, d}) {
return [
ka * a[0] + kb * b[0] + kc * c[0] + kd * d[0],
ka * a[1] + kb * b[1] + kc * c[1] + kd * d[1]
];
}

return class BezierCurve {
constructor(a, b, c, d) {
this.a = a;
this.b = b;
this.c = c;
this.d = d;
}
split() {
const m = dot(l3, this);
return [
new BezierCurve(this.a, dot(l1, this), dot(l2, this), m),
new BezierCurve(m, dot(r1, this), dot(r2, this), this.d)
];
}
toString() {
return `M${this.a}C${this.b},${this.c},${this.d}`;
}
};
}
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line = d3.lineRadial()
.curve(d3.curveBundle)
.radius(d => d.y)
.angle(d => d.x)
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tree = d3.cluster()
.size([2 * Math.PI, radius - 100])
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color = t => d3.interpolateMagma(t)
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d3.co
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k = 6 // 2^k colors segments per curve
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width = 954
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radius = width / 2
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d3 = require("d3@5")
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