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().strength(-30.5))
.force("center", d3.forceCenter(width / 2, height / 2));
const svg = d3.create("svg")
.attr("viewBox", [0, 0, width, height]);
const link = svg.append("g")
.attr("stroke", "#999")
.attr("stroke-opacity", 0.6)
.selectAll("line")
.data(links)
.join("line")
.attr("stroke-width", d => Math.sqrt(d.value));
const node = svg.append("g")
.selectAll(".node")
.data(nodes)
.join("g")
.attr('class', 'node')
.call(drag(simulation));
node.append('circle')
.attr("r", 5)
.attr("fill", color);
node.append("text")
.text(function(d) {
return d.name;
})
.style('fill', '#000')
.style('font-size', '12px')
.attr('x', 6)
.attr('y', 3);
simulation.on("tick", () => {
link
.attr("x1", d => d.source.x)
.attr("y1", d => d.source.y)
.attr("x2", d => d.target.x)
.attr("y2", d => d.target.y);
node
.attr("transform", d => `translate(${d.x}, ${d.y})`);
});
invalidation.then(() => simulation.stop());
return svg.node();
}