chart = {
const links = data.links.map(d => Object.create(d));
const nodes = data.nodes.map(d => Object.create(d));
const simulation = d3.forceSimulation(nodes)
.force("link", d3.forceLink(links).id(d => d.id))
.force("charge", d3.forceManyBody())
.force("x", d3.forceX())
.force("y", d3.forceY());
const svg = d3.create("svg")
.attr("viewBox", [-width / 2, -height / 2, width, height]);
const bg = svg.append("rect")
.attr("x", "-477")
.attr("y", "-400")
.attr("width", "100%")
.attr("height", "100%")
.attr("fill", "#F5F7FA");
const nodeBG = svg.append("g")
.selectAll("circle")
.data(nodes)
.join("circle")
.attr("fill", "hsla(259,100%,66%,1)")
.attr("r", 14)
.call(drag(simulation));
const link = svg.append("g")
.attr("stroke", "#8954FF")
.attr("stroke-opacity", 1)
.selectAll("line")
.data(links)
.join("line")
.attr("stroke-width", d => Math.sqrt(d.value));
const node = svg.append("g")
.selectAll("circle")
.data(nodes)
.join("circle")
.attr("fill", d => d.children ? null : "#fff")
.attr("stroke", d => d.children ? null : "#fff")
.attr("r", 6)
.call(drag(simulation));
node.append("title")
.text(d => d.id);
simulation.on("tick", () => {
link
.attr("x1", d => d.source.x+4)
.attr("y1", d => d.source.y+6.5)
.attr("x2", d => d.target.x+4)
.attr("y2", d => d.target.y+6.5);
node
.attr("cx", d => d.x)
.attr("cy", d => d.y);
nodeBG
.attr("cx", d => d.x)
.attr("cy", d => d.y);
});
invalidation.then(() => simulation.stop());
return svg.node();
}