async function drawGraph(baseUrl, isHome, pathColors, graphConfig) { let { depth, enableDrag, enableLegend, enableZoom, opacityScale, scale, repelForce, fontSize } = graphConfig; const container = document.getElementById("graph-container") const { index, links, content } = await fetchData // Use .pathname to remove hashes / searchParams / text fragments const cleanUrl = window.location.origin + window.location.pathname const curPage = cleanUrl.replace(/\/$/g, "").replace(baseUrl, "") const parseIdsFromLinks = (links) => [ ...new Set(links.flatMap((link) => [link.source, link.target])), ] // Links is mutated by d3. We want to use links later on, so we make a copy and pass that one to d3 // Note: shallow cloning does not work because it copies over references from the original array const copyLinks = JSON.parse(JSON.stringify(links)) const neighbours = new Set() const wl = [curPage || "/", "__SENTINEL"] if (depth >= 0) { while (depth >= 0 && wl.length > 0) { // compute neighbours const cur = wl.shift() if (cur === "__SENTINEL") { depth-- wl.push("__SENTINEL") } else { neighbours.add(cur) const outgoing = index.links[cur] || [] const incoming = index.backlinks[cur] || [] wl.push(...outgoing.map((l) => l.target), ...incoming.map((l) => l.source)) } } } else { parseIdsFromLinks(copyLinks).forEach((id) => neighbours.add(id)) } const data = { nodes: [...neighbours].map((id) => ({ id })), links: copyLinks.filter((l) => neighbours.has(l.source) && neighbours.has(l.target)), } const color = (d) => { if (d.id === curPage || (d.id === "/" && curPage === "")) { return "var(--g-node-active)" } for (const pathColor of pathColors) { const path = Object.keys(pathColor)[0] const colour = pathColor[path] if (d.id.startsWith(path)) { return colour } } return "var(--g-node)" } const drag = (simulation) => { function dragstarted(event, d) { if (!event.active) simulation.alphaTarget(1).restart() d.fx = d.x d.fy = d.y } function dragged(event, d) { d.fx = event.x d.fy = event.y } function dragended(event, d) { if (!event.active) simulation.alphaTarget(0) d.fx = null d.fy = null } const noop = () => { } return d3 .drag() .on("start", enableDrag ? dragstarted : noop) .on("drag", enableDrag ? dragged : noop) .on("end", enableDrag ? dragended : noop) } const height = Math.max(container.offsetHeight, isHome ? 500 : 250) const width = container.offsetWidth const simulation = d3 .forceSimulation(data.nodes) .force("charge", d3.forceManyBody().strength(-100 * repelForce)) .force( "link", d3 .forceLink(data.links) .id((d) => d.id) .distance(40), ) .force("center", d3.forceCenter()) const svg = d3 .select("#graph-container") .append("svg") .attr("width", width) .attr("height", height) .attr('viewBox', [-width / 2 / scale, -height / 2 / scale, width / scale, height / scale]) if (enableLegend) { const legend = [{ Current: "var(--g-node-active)" }, { Note: "var(--g-node)" }, ...pathColors] legend.forEach((legendEntry, i) => { const key = Object.keys(legendEntry)[0] const colour = legendEntry[key] svg .append("circle") .attr("cx", -width / 2 + 20) .attr("cy", height / 2 - 30 * (i + 1)) .attr("r", 6) .style("fill", colour) svg .append("text") .attr("x", -width / 2 + 40) .attr("y", height / 2 - 30 * (i + 1)) .text(key) .style("font-size", "15px") .attr("alignment-baseline", "middle") }) } // draw links between nodes const link = svg .append("g") .selectAll("line") .data(data.links) .join("line") .attr("class", "link") .attr("stroke", "var(--g-link)") .attr("stroke-width", 2) .attr("data-source", (d) => d.source.id) .attr("data-target", (d) => d.target.id) // svg groups const graphNode = svg.append("g").selectAll("g").data(data.nodes).enter().append("g") // calculate radius const nodeRadius = (d) => { const numOut = index.links[d.id]?.length || 0 const numIn = index.backlinks[d.id]?.length || 0 return 2 + Math.sqrt(numOut + numIn) } // draw individual nodes const node = graphNode .append("circle") .attr("class", "node") .attr("id", (d) => d.id) .attr("r", nodeRadius) .attr("fill", color) .style("cursor", "pointer") .on("click", (_, d) => { // SPA navigation const targ = `${baseUrl}${decodeURI(d.id).replace(/\s+/g, "-")}/` window.Million.navigate(new URL(targ), ".singlePage") plausible("Link Click", { props: { href: targ, broken: false, internal: true, graph: true, } }) }) .on("mouseover", function (_, d) { d3.selectAll(".node").transition().duration(100).attr("fill", "var(--g-node-inactive)") const neighbours = parseIdsFromLinks([ ...(index.links[d.id] || []), ...(index.backlinks[d.id] || []), ]) const neighbourNodes = d3.selectAll(".node").filter((d) => neighbours.includes(d.id)) const currentId = d.id window.Million.prefetch(new URL(`${baseUrl}${decodeURI(d.id).replace(/\s+/g, "-")}/`)) const linkNodes = d3 .selectAll(".link") .filter((d) => d.source.id === currentId || d.target.id === currentId) // highlight neighbour nodes neighbourNodes.transition().duration(200).attr("fill", color) // highlight links linkNodes.transition().duration(200).attr("stroke", "var(--g-link-active)") const bigFont = fontSize * 1.5 // show text for self d3.select(this.parentNode) .raise() .select("text") .transition() .duration(200) .attr('opacityOld', d3.select(this.parentNode).select('text').style("opacity")) .style('opacity', 1) .style('font-size', bigFont + 'em') .attr('dy', d => nodeRadius(d) + 20 + 'px') // radius is in px }) .on("mouseleave", function (_, d) { d3.selectAll(".node").transition().duration(200).attr("fill", color) const currentId = d.id const linkNodes = d3 .selectAll(".link") .filter((d) => d.source.id === currentId || d.target.id === currentId) linkNodes.transition().duration(200).attr("stroke", "var(--g-link)") d3.select(this.parentNode) .select("text") .transition() .duration(200) .style('opacity', d3.select(this.parentNode).select('text').attr("opacityOld")) .style('font-size', fontSize + 'em') .attr('dy', d => nodeRadius(d) + 8 + 'px') // radius is in px }) .call(drag(simulation)) // draw labels const labels = graphNode .append("text") .attr("dx", 0) .attr("dy", (d) => nodeRadius(d) + 8 + "px") .attr("text-anchor", "middle") .text((d) => { const str = content[d.id]?.title || decodeURI(d.id.charAt(1).toUpperCase() + d.id.slice(2)) .replace("-", " "); str.slice(0, 30) + str.length > 30 ? "..." : "" }) .style('opacity', (opacityScale - 1) / 3.75) .style("pointer-events", "none") .style('font-size', fontSize + 'em') .raise() .call(drag(simulation)) // set panning if (enableZoom) { svg.call( d3 .zoom() .extent([ [0, 0], [width, height], ]) .scaleExtent([0.25, 4]) .on("zoom", ({ transform }) => { link.attr("transform", transform) node.attr("transform", transform) const scale = transform.k * opacityScale; const scaledOpacity = Math.max((scale - 1) / 3.75, 0) labels.attr("transform", transform).style("opacity", scaledOpacity) }), ) } // progress the simulation 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("cx", (d) => d.x).attr("cy", (d) => d.y) labels.attr("x", (d) => d.x).attr("y", (d) => d.y) }) }