Published unlisted
Edited
Jul 10, 2021
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# Fisheye test
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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();
}
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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();
}
})

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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);
}


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