Published unlisted
Edited
Jul 10, 2021
Insert cell
# Fisheye test
Insert cell
chart = {
const fisheye = fisheyeO.circular()
.radius(100)
.distortion(5);

const simulation = d3.forceSimulation(nodes)
.alphaDecay(0.125)
.alphaMin(0.01)
.force("link", d3.forceLink(links).id(d => d.id))
.force("charge", d3.forceManyBody())
.force("x", d3.forceX(width/2))
.force("y", d3.forceY(height/2));

const svg = d3.create("svg")
.attr("viewBox", [0, 0, width, height])
.on("mousemove", d=>fisheye.focus(d3.mouse(this)));

const link = svg.append("g")
.attr("stroke", "#999")
.attr("stroke-opacity", 0.6)
.selectAll("line")
.data(links)
.join("line")
.attr("stroke-width", 2);
const node = svg.append("g")
.attr("stroke", "#fff")
.attr("stroke-width", 1.5)
.selectAll("circle")
.data(nodes)
.join("circle")
.attr("r", 5)
.attr("fill", "black")
.call(drag(simulation));

node.append("title")
.text(d => d.id);

svg.on("mousemove", function() {
fisheye.focus(d3.mouse(this));

node.each(function(d) { d.fisheye = fisheye(d); })
.attr("cx", function(d) { return d.fisheye.x; })
.attr("cy", function(d) { return d.fisheye.y; })
.attr("r", function(d) { return d.fisheye.z * 4.5; });

link.attr("x1", function(d) { return d.source.fisheye.x; })
.attr("y1", function(d) { return d.source.fisheye.y; })
.attr("x2", function(d) { return d.target.fisheye.x; })
.attr("y2", function(d) { return d.target.fisheye.y; });
})

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);
});


return svg.node();
}
Insert cell
fisheyeO = ({
circular: () => {
var radius = 200,
distortion = 2,
k0,
k1,
focus = [0, 0];

function fisheye(d) {
var dx = d.x - focus[0],
dy = d.y - focus[1],
dd = Math.sqrt(dx * dx + dy * dy);
if (!dd || dd >= radius) return {x: d.x, y: d.y, z: dd >= radius ? 1 : 10};
var k = k0 * (1 - Math.exp(-dd * k1)) / dd * .75 + .25;
return {x: focus[0] + dx * k, y: focus[1] + dy * k, z: Math.min(k, 10)};
}

function rescale() {
k0 = Math.exp(distortion);
k0 = k0 / (k0 - 1) * radius;
k1 = distortion / radius;
return fisheye;
}

fisheye.radius = function(_) {
if (!arguments.length) return radius;
radius = +_;
return rescale();
};

fisheye.distortion = function(_) {
if (!arguments.length) return distortion;
distortion = +_;
return rescale();
};

fisheye.focus = function(_) {
if (!arguments.length) return focus;
focus = _;
return fisheye;
};

return rescale();
}
})

Insert cell
drag = simulation => {
function dragstarted(d) {
if (!d3.event.active) simulation.alphaTarget(0.3).restart();
d.fx = d.x;
d.fy = d.y;
}
function dragged(d) {
d.fx = d3.event.x;
d.fy = d3.event.y;
}
function dragended(d) {
if (!d3.event.active) simulation.alphaTarget(0);
d.fx = null;
d.fy = null;
}
return d3.drag()
.on("start", dragstarted)
.on("drag", dragged)
.on("end", dragended);
}


Insert cell
data = d3.json("https://gist.githubusercontent.com/mbostock/4062045/raw/5916d145c8c048a6e3086915a6be464467391c62/miserables.json")
Insert cell
nodes = data.nodes.map(d => Object.create(d));
Insert cell
Insert cell
height = 400
Insert cell
d3 = require("d3@5")
Insert cell

One platform to build and deploy the best data apps

Experiment and prototype by building visualizations in live JavaScript notebooks. Collaborate with your team and decide which concepts to build out.
Use Observable Framework to build data apps locally. Use data loaders to build in any language or library, including Python, SQL, and R.
Seamlessly deploy to Observable. Test before you ship, use automatic deploy-on-commit, and ensure your projects are always up-to-date.
Learn more