This demonstrates forceLink.iterations, which strengthens d3-force’s link constraint by applying the constraint multiple times per simulation step.
-
-
Save bcrisp/06e37b1f530b8f934dffef5423f91088 to your computer and use it in GitHub Desktop.
Force-Directed Lattice
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| license: gpl-3.0 | |
| height: 960 |
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| <!DOCTYPE html> | |
| <meta charset="utf-8"> | |
| <canvas width="960" height="960"></canvas> | |
| <script src="https://d3js.org/d3.v4.min.js"></script> | |
| <script> | |
| var n = 10; | |
| var nodes = d3.range(n * n).map(function(i) { | |
| return { | |
| index: i | |
| }; | |
| }); | |
| var links = []; | |
| for (var y = 0; y < n; ++y) { | |
| for (var x = 0; x < n; ++x) { | |
| if (y > 0) links.push({source: (y - 1) * n + x, target: y * n + x}); | |
| if (x > 0) links.push({source: y * n + (x - 1), target: y * n + x}); | |
| } | |
| } | |
| var simulation = d3.forceSimulation(nodes) | |
| .force("charge", d3.forceManyBody().strength(-30)) | |
| .force("link", d3.forceLink(links).strength(1).distance(20).iterations(10)) | |
| .on("tick", ticked); | |
| var canvas = document.querySelector("canvas"), | |
| context = canvas.getContext("2d"), | |
| width = canvas.width, | |
| height = canvas.height; | |
| d3.select(canvas) | |
| .call(d3.drag() | |
| .container(canvas) | |
| .subject(dragsubject) | |
| .on("start", dragstarted) | |
| .on("drag", dragged) | |
| .on("end", dragended)); | |
| function ticked() { | |
| context.clearRect(0, 0, width, height); | |
| context.save(); | |
| context.translate(width / 2, height / 2); | |
| context.beginPath(); | |
| links.forEach(drawLink); | |
| context.strokeStyle = "#aaa"; | |
| context.stroke(); | |
| context.beginPath(); | |
| nodes.forEach(drawNode); | |
| context.fill(); | |
| context.strokeStyle = "#fff"; | |
| context.stroke(); | |
| context.restore(); | |
| } | |
| function dragsubject() { | |
| return simulation.find(d3.event.x - width / 2, d3.event.y - height / 2); | |
| } | |
| function dragstarted() { | |
| if (!d3.event.active) simulation.alphaTarget(0.3).restart(); | |
| d3.event.subject.fx = d3.event.subject.x; | |
| d3.event.subject.fy = d3.event.subject.y; | |
| } | |
| function dragged() { | |
| d3.event.subject.fx = d3.event.x; | |
| d3.event.subject.fy = d3.event.y; | |
| } | |
| function dragended() { | |
| if (!d3.event.active) simulation.alphaTarget(0); | |
| d3.event.subject.fx = null; | |
| d3.event.subject.fy = null; | |
| } | |
| function drawLink(d) { | |
| context.moveTo(d.source.x, d.source.y); | |
| context.lineTo(d.target.x, d.target.y); | |
| } | |
| function drawNode(d) { | |
| context.moveTo(d.x + 3, d.y); | |
| context.arc(d.x, d.y, 3, 0, 2 * Math.PI); | |
| } | |
| </script> |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment