async function drawGraph(url, baseUrl, pathColors, depth, enableDrag, enableLegend, enableZoom) { if (!document.getElementById("graph-container")) return; document.getElementById("graph-container").textContent = ""; const { index, links, content } = await fetchData; const curPage = url.replace(baseUrl, ""); const parseIdsFromLinks = (links) => [ ...new Set(links.flatMap((link) => [link.source, link.target])), ]; 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(document.getElementById("graph-container").offsetHeight, 250); const width = document.getElementById("graph-container").offsetWidth; const simulation = d3 .forceSimulation(data.nodes) .force("charge", d3.forceManyBody().strength(-30)) .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, -height / 2, width, height]); 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 3 + (numOut + numIn) / 4; }; // 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) => { window.navigate(new URL(`${baseUrl}${decodeURI(d.id).replace(/\s+/g, "-")}/`), ".singlePage"); }) .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; 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)"); // show text for self d3.select(this.parentNode) .raise() .select("text") .transition() .duration(200) .style("opacity", 1); }) .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", 0); }) .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) => content[d.id]?.title || d.id.replace("-", " ")) .style("opacity", 0) .style("pointer-events", "none") .style("font-size", "0.4em") .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; 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); }); }