Skip to content

Instantly share code, notes, and snippets.

@fernoftheandes

fernoftheandes/README.md

Last active November 30, 2019 21:55
Show Gist options
  • Save fernoftheandes/8637581 to your computer and use it in GitHub Desktop.
Save fernoftheandes/8637581 to your computer and use it in GitHub Desktop.
Download ZIP
Encircling D3's Fisheye Distortion
Raw
README.md

Except for the code segments that render the magnifying glass (as circle or path), this is essentially a copy of Mike Bostock's Fisheye Distortion example.

The motivation for this was largely aesthetical but also a bit functional. When using the Fisheye as an aid to viewing large datasets, I often find myself experimenting with the degree and radius of the distortion. In such cases, I find it helpful to see the exact reach of the distortion and then decide the best configuration for a particular dataset.

Raw
fisheye.js
(function() {
d3.fisheye = {
scale: function(scaleType) {
return d3_fisheye_scale(scaleType(), 3, 0);
},
circular: function() {
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: 1};
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();
}
};
function d3_fisheye_scale(scale, d, a) {
function fisheye(_) {
var x = scale(_),
left = x < a,
range = d3.extent(scale.range()),
min = range[0],
max = range[1],
m = left ? a - min : max - a;
if (m == 0) m = max - min;
return (left ? -1 : 1) * m * (d + 1) / (d + (m / Math.abs(x - a))) + a;
}
fisheye.distortion = function(_) {
if (!arguments.length) return d;
d = +_;
return fisheye;
};
fisheye.focus = function(_) {
if (!arguments.length) return a;
a = +_;
return fisheye;
};
fisheye.copy = function() {
return d3_fisheye_scale(scale.copy(), d, a);
};
fisheye.nice = scale.nice;
fisheye.ticks = scale.ticks;
fisheye.tickFormat = scale.tickFormat;
return d3.rebind(fisheye, scale, "domain", "range");
}
})();
Raw
index.html
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
<TITLE>Encircling D3 Fisheye Distortion</TITLE>
<script type="text/javascript" src="https://d3js.org/d3.v3.min.js"></script>
<script type="text/javascript" src="fisheye.js"></script>
<style>
.background {
fill: none;
pointer-events: all;
}
/*
#chart1 {
width: 960px;
height: 600px;
border: solid 1px #ccc;
}
*/
#chart1 .circle {
stroke: #fff;
stroke-width: 1.5px;
}
#chart1 .link {
stroke: #999;
stroke-opacity: .6;
stroke-width: 1.5px;
}
text {
font: 12px sans-serif;
pointer-events: none;
text-anchor: start;
}
/* magnifier glass as circle */
.lens {
stroke: gray;
stroke-width: 2.0px;
stroke-opacity: 0;
fill: none;
}
/* magnifier glass as path */
.mag {
stroke: gray;
stroke-width: 2.0px;
stroke-opacity: 0;
fill: none;
}
/* magnifier handle as path */
.mag2 {
stroke: black;
stroke-width: 12.0px;
stroke-opacity: 0;
fill: none;
}
</style>
</head>
<body bgcolor="white">
<form style="margin-left: 20px">
<input type="radio" name="wot" id="circle" value="one" />&nbsp;as circle<br/>
<input type="radio" name="wot" id="path" value="two" checked />&nbsp;as path
</form>
<div id="chart1"></div>
<script>
var width = 960,
height = 600;
var color = d3.scale.category20();
var fisheye = d3.fisheye.circular()
.radius(100)
.distortion(5);
var force = d3.layout.force()
.charge(-440)
.linkDistance(60)
.size([width, height]);
var svg = d3.select("#chart1").append("svg")
.attr("width", width)
.attr("height", height);
// magnifier as circle
var lens = svg.append("circle")
.attr("class","lens")
.attr("r", fisheye.radius());;
// magnifier as path
var mag = svg.append("path")
.attr("class", "mag");
// specify angle where magnifier handle should "attach" to body
var omega = 0.78;
// magnifier handle as path
var mag2 = svg.append("path")
.attr("class", "mag2");
/*
svg.append("rect")
.attr("class", "background")
.attr("width", width)
.attr("height", height);
*/
d3.json("miserables.json", function(data) {
var n = data.nodes.length;
force.nodes(data.nodes).links(data.links);
// Initialize the positions deterministically, for better results.
data.nodes.forEach(function(d, i) { d.x = d.y = width / n * i; });
// Run the layout a fixed number of times.
// The ideal number of times scales with graph complexity.
// Of course, don't run too long—you'll hang the page!
force.start();
for (var i = n; i > 0; --i) force.tick();
force.stop();
// Center the nodes in the middle.
var ox = 0, oy = 0;
data.nodes.forEach(function(d) { ox += d.x, oy += d.y; });
ox = ox / n - width / 2, oy = oy / n - height / 2;
data.nodes.forEach(function(d) { d.x -= ox, d.y -= oy; });
var link = svg.selectAll(".link")
.data(data.links)
.enter().append("line")
.attr("class", "link")
.attr("x1", function(d) { return d.source.x; })
.attr("y1", function(d) { return d.source.y; })
.attr("x2", function(d) { return d.target.x; })
.attr("y2", function(d) { return d.target.y; })
.style("stroke-width", function(d) { return Math.sqrt(d.value); });
var node = svg.selectAll(".node")
.data(data.nodes)
.enter().append("g")
.attr("class", "node");
render("path");
function render(shape) {
node.selectAll(".link").remove();
node.selectAll(".circle").remove();
node.selectAll(".text").remove();
lens.style("stroke-opacity", shape == "circle" ? 1 : 0);
mag.style("stroke-opacity", shape == "path" ? 1 : 0);
mag2.style("stroke-opacity", shape == "path" ? 1 : 0);
var nodeEnter = node
.append("circle")
.attr("class", "circle")
.attr("cx", function(d) { return d.x; })
.attr("cy", function(d) { return d.y; })
.attr("r", 6)
.style("fill", function(d) { return color(d.group); })
.call(force.drag);
var text = node.append("text")
.attr("class", "text")
.attr("dy", function(d) { return d.y; })
.attr("dx", function(d) { return d.x; })
.text(function(d) { return d.name; });
node.append("title")
.text(function(d) { return d.name; });
svg.on("mousemove", function() {
fisheye.focus(d3.mouse(this));
var mouseX = d3.mouse(this)[0];
var mouseY = d3.mouse(this)[1];
var r = fisheye.radius();
if (shape == "circle") {
// display magnifier as circle
lens
.attr("cx", mouseX)
.attr("cy", mouseY);
}
else {
// path for magnifier
var magPath = "M " + mouseX + "," + mouseY + " m -" + r + ", 0 a " + r + "," + r + " 0 1,0 " + (r * 2) + ",0 a " + r + "," + r + " 0 1,0 -" + (r * 2) + ",0";
// point in circumference to attach magnifier handle
var x1 = mouseX + r * Math.sin(omega);
var y1 = mouseY + r * Math.cos(omega);
// path for magnifier's handle
var mag2Path = "M " + (x1 + 2) + "," + (y1 + 2) + " L" + (mouseX + r * 1.7) + "," + (mouseY + r * 1.7);
// display magnifier as path
mag.attr("d", magPath);
// display magnifier handle as path
mag2.attr("d", mag2Path);
};
nodeEnter.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; });
text.attr("dx", function(d) { return d.fisheye.x; })
.attr("dy", function(d) { return d.fisheye.y; });
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; });
});
}
d3.select("#circle").on("click", function () { render("circle");});
d3.select("#path").on("click", function () { render("path");});
})
</script>
</body>
</html>
Raw
miserables.json
{
"nodes":[
{"name":"Myriel","group":1},
{"name":"Napoleon","group":1},
{"name":"Mlle.Baptistine","group":1},
{"name":"Mme.Magloire","group":1},
{"name":"CountessdeLo","group":1},
{"name":"Geborand","group":1},
{"name":"Champtercier","group":1},
{"name":"Cravatte","group":1},
{"name":"Count","group":1},
{"name":"OldMan","group":1},
{"name":"Labarre","group":2},
{"name":"Valjean","group":2},
{"name":"Marguerite","group":3},
{"name":"Mme.deR","group":2},
{"name":"Isabeau","group":2},
{"name":"Gervais","group":2},
{"name":"Tholomyes","group":3},
{"name":"Listolier","group":3},
{"name":"Fameuil","group":3},
{"name":"Blacheville","group":3},
{"name":"Favourite","group":3},
{"name":"Dahlia","group":3},
{"name":"Zephine","group":3},
{"name":"Fantine","group":3},
{"name":"Mme.Thenardier","group":4},
{"name":"Thenardier","group":4},
{"name":"Cosette","group":5},
{"name":"Javert","group":4},
{"name":"Fauchelevent","group":0},
{"name":"Bamatabois","group":2},
{"name":"Perpetue","group":3},
{"name":"Simplice","group":2},
{"name":"Scaufflaire","group":2},
{"name":"Woman1","group":2},
{"name":"Judge","group":2},
{"name":"Champmathieu","group":2},
{"name":"Brevet","group":2},
{"name":"Chenildieu","group":2},
{"name":"Cochepaille","group":2},
{"name":"Pontmercy","group":4},
{"name":"Boulatruelle","group":6},
{"name":"Eponine","group":4},
{"name":"Anzelma","group":4},
{"name":"Woman2","group":5},
{"name":"MotherInnocent","group":0},
{"name":"Gribier","group":0},
{"name":"Jondrette","group":7},
{"name":"Mme.Burgon","group":7},
{"name":"Gavroche","group":8},
{"name":"Gillenormand","group":5},
{"name":"Magnon","group":5},
{"name":"Mlle.Gillenormand","group":5},
{"name":"Mme.Pontmercy","group":5},
{"name":"Mlle.Vaubois","group":5},
{"name":"Lt.Gillenormand","group":5},
{"name":"Marius","group":8},
{"name":"BaronessT","group":5},
{"name":"Mabeuf","group":8},
{"name":"Enjolras","group":8},
{"name":"Combeferre","group":8},
{"name":"Prouvaire","group":8},
{"name":"Feuilly","group":8},
{"name":"Courfeyrac","group":8},
{"name":"Bahorel","group":8},
{"name":"Bossuet","group":8},
{"name":"Joly","group":8},
{"name":"Grantaire","group":8},
{"name":"MotherPlutarch","group":9},
{"name":"Gueulemer","group":4},
{"name":"Babet","group":4},
{"name":"Claquesous","group":4},
{"name":"Montparnasse","group":4},
{"name":"Toussaint","group":5},
{"name":"Child1","group":10},
{"name":"Child2","group":10},
{"name":"Brujon","group":4},
{"name":"Mme.Hucheloup","group":8}
],
"links":[
{"source":1,"target":0,"value":1},
{"source":2,"target":0,"value":8},
{"source":3,"target":0,"value":10},
{"source":3,"target":2,"value":6},
{"source":4,"target":0,"value":1},
{"source":5,"target":0,"value":1},
{"source":6,"target":0,"value":1},
{"source":7,"target":0,"value":1},
{"source":8,"target":0,"value":2},
{"source":9,"target":0,"value":1},
{"source":11,"target":10,"value":1},
{"source":11,"target":3,"value":3},
{"source":11,"target":2,"value":3},
{"source":11,"target":0,"value":5},
{"source":12,"target":11,"value":1},
{"source":13,"target":11,"value":1},
{"source":14,"target":11,"value":1},
{"source":15,"target":11,"value":1},
{"source":17,"target":16,"value":4},
{"source":18,"target":16,"value":4},
{"source":18,"target":17,"value":4},
{"source":19,"target":16,"value":4},
{"source":19,"target":17,"value":4},
{"source":19,"target":18,"value":4},
{"source":20,"target":16,"value":3},
{"source":20,"target":17,"value":3},
{"source":20,"target":18,"value":3},
{"source":20,"target":19,"value":4},
{"source":21,"target":16,"value":3},
{"source":21,"target":17,"value":3},
{"source":21,"target":18,"value":3},
{"source":21,"target":19,"value":3},
{"source":21,"target":20,"value":5},
{"source":22,"target":16,"value":3},
{"source":22,"target":17,"value":3},
{"source":22,"target":18,"value":3},
{"source":22,"target":19,"value":3},
{"source":22,"target":20,"value":4},
{"source":22,"target":21,"value":4},
{"source":23,"target":16,"value":3},
{"source":23,"target":17,"value":3},
{"source":23,"target":18,"value":3},
{"source":23,"target":19,"value":3},
{"source":23,"target":20,"value":4},
{"source":23,"target":21,"value":4},
{"source":23,"target":22,"value":4},
{"source":23,"target":12,"value":2},
{"source":23,"target":11,"value":9},
{"source":24,"target":23,"value":2},
{"source":24,"target":11,"value":7},
{"source":25,"target":24,"value":13},
{"source":25,"target":23,"value":1},
{"source":25,"target":11,"value":12},
{"source":26,"target":24,"value":4},
{"source":26,"target":11,"value":31},
{"source":26,"target":16,"value":1},
{"source":26,"target":25,"value":1},
{"source":27,"target":11,"value":17},
{"source":27,"target":23,"value":5},
{"source":27,"target":25,"value":5},
{"source":27,"target":24,"value":1},
{"source":27,"target":26,"value":1},
{"source":28,"target":11,"value":8},
{"source":28,"target":27,"value":1},
{"source":29,"target":23,"value":1},
{"source":29,"target":27,"value":1},
{"source":29,"target":11,"value":2},
{"source":30,"target":23,"value":1},
{"source":31,"target":30,"value":2},
{"source":31,"target":11,"value":3},
{"source":31,"target":23,"value":2},
{"source":31,"target":27,"value":1},
{"source":32,"target":11,"value":1},
{"source":33,"target":11,"value":2},
{"source":33,"target":27,"value":1},
{"source":34,"target":11,"value":3},
{"source":34,"target":29,"value":2},
{"source":35,"target":11,"value":3},
{"source":35,"target":34,"value":3},
{"source":35,"target":29,"value":2},
{"source":36,"target":34,"value":2},
{"source":36,"target":35,"value":2},
{"source":36,"target":11,"value":2},
{"source":36,"target":29,"value":1},
{"source":37,"target":34,"value":2},
{"source":37,"target":35,"value":2},
{"source":37,"target":36,"value":2},
{"source":37,"target":11,"value":2},
{"source":37,"target":29,"value":1},
{"source":38,"target":34,"value":2},
{"source":38,"target":35,"value":2},
{"source":38,"target":36,"value":2},
{"source":38,"target":37,"value":2},
{"source":38,"target":11,"value":2},
{"source":38,"target":29,"value":1},
{"source":39,"target":25,"value":1},
{"source":40,"target":25,"value":1},
{"source":41,"target":24,"value":2},
{"source":41,"target":25,"value":3},
{"source":42,"target":41,"value":2},
{"source":42,"target":25,"value":2},
{"source":42,"target":24,"value":1},
{"source":43,"target":11,"value":3},
{"source":43,"target":26,"value":1},
{"source":43,"target":27,"value":1},
{"source":44,"target":28,"value":3},
{"source":44,"target":11,"value":1},
{"source":45,"target":28,"value":2},
{"source":47,"target":46,"value":1},
{"source":48,"target":47,"value":2},
{"source":48,"target":25,"value":1},
{"source":48,"target":27,"value":1},
{"source":48,"target":11,"value":1},
{"source":49,"target":26,"value":3},
{"source":49,"target":11,"value":2},
{"source":50,"target":49,"value":1},
{"source":50,"target":24,"value":1},
{"source":51,"target":49,"value":9},
{"source":51,"target":26,"value":2},
{"source":51,"target":11,"value":2},
{"source":52,"target":51,"value":1},
{"source":52,"target":39,"value":1},
{"source":53,"target":51,"value":1},
{"source":54,"target":51,"value":2},
{"source":54,"target":49,"value":1},
{"source":54,"target":26,"value":1},
{"source":55,"target":51,"value":6},
{"source":55,"target":49,"value":12},
{"source":55,"target":39,"value":1},
{"source":55,"target":54,"value":1},
{"source":55,"target":26,"value":21},
{"source":55,"target":11,"value":19},
{"source":55,"target":16,"value":1},
{"source":55,"target":25,"value":2},
{"source":55,"target":41,"value":5},
{"source":55,"target":48,"value":4},
{"source":56,"target":49,"value":1},
{"source":56,"target":55,"value":1},
{"source":57,"target":55,"value":1},
{"source":57,"target":41,"value":1},
{"source":57,"target":48,"value":1},
{"source":58,"target":55,"value":7},
{"source":58,"target":48,"value":7},
{"source":58,"target":27,"value":6},
{"source":58,"target":57,"value":1},
{"source":58,"target":11,"value":4},
{"source":59,"target":58,"value":15},
{"source":59,"target":55,"value":5},
{"source":59,"target":48,"value":6},
{"source":59,"target":57,"value":2},
{"source":60,"target":48,"value":1},
{"source":60,"target":58,"value":4},
{"source":60,"target":59,"value":2},
{"source":61,"target":48,"value":2},
{"source":61,"target":58,"value":6},
{"source":61,"target":60,"value":2},
{"source":61,"target":59,"value":5},
{"source":61,"target":57,"value":1},
{"source":61,"target":55,"value":1},
{"source":62,"target":55,"value":9},
{"source":62,"target":58,"value":17},
{"source":62,"target":59,"value":13},
{"source":62,"target":48,"value":7},
{"source":62,"target":57,"value":2},
{"source":62,"target":41,"value":1},
{"source":62,"target":61,"value":6},
{"source":62,"target":60,"value":3},
{"source":63,"target":59,"value":5},
{"source":63,"target":48,"value":5},
{"source":63,"target":62,"value":6},
{"source":63,"target":57,"value":2},
{"source":63,"target":58,"value":4},
{"source":63,"target":61,"value":3},
{"source":63,"target":60,"value":2},
{"source":63,"target":55,"value":1},
{"source":64,"target":55,"value":5},
{"source":64,"target":62,"value":12},
{"source":64,"target":48,"value":5},
{"source":64,"target":63,"value":4},
{"source":64,"target":58,"value":10},
{"source":64,"target":61,"value":6},
{"source":64,"target":60,"value":2},
{"source":64,"target":59,"value":9},
{"source":64,"target":57,"value":1},
{"source":64,"target":11,"value":1},
{"source":65,"target":63,"value":5},
{"source":65,"target":64,"value":7},
{"source":65,"target":48,"value":3},
{"source":65,"target":62,"value":5},
{"source":65,"target":58,"value":5},
{"source":65,"target":61,"value":5},
{"source":65,"target":60,"value":2},
{"source":65,"target":59,"value":5},
{"source":65,"target":57,"value":1},
{"source":65,"target":55,"value":2},
{"source":66,"target":64,"value":3},
{"source":66,"target":58,"value":3},
{"source":66,"target":59,"value":1},
{"source":66,"target":62,"value":2},
{"source":66,"target":65,"value":2},
{"source":66,"target":48,"value":1},
{"source":66,"target":63,"value":1},
{"source":66,"target":61,"value":1},
{"source":66,"target":60,"value":1},
{"source":67,"target":57,"value":3},
{"source":68,"target":25,"value":5},
{"source":68,"target":11,"value":1},
{"source":68,"target":24,"value":1},
{"source":68,"target":27,"value":1},
{"source":68,"target":48,"value":1},
{"source":68,"target":41,"value":1},
{"source":69,"target":25,"value":6},
{"source":69,"target":68,"value":6},
{"source":69,"target":11,"value":1},
{"source":69,"target":24,"value":1},
{"source":69,"target":27,"value":2},
{"source":69,"target":48,"value":1},
{"source":69,"target":41,"value":1},
{"source":70,"target":25,"value":4},
{"source":70,"target":69,"value":4},
{"source":70,"target":68,"value":4},
{"source":70,"target":11,"value":1},
{"source":70,"target":24,"value":1},
{"source":70,"target":27,"value":1},
{"source":70,"target":41,"value":1},
{"source":70,"target":58,"value":1},
{"source":71,"target":27,"value":1},
{"source":71,"target":69,"value":2},
{"source":71,"target":68,"value":2},
{"source":71,"target":70,"value":2},
{"source":71,"target":11,"value":1},
{"source":71,"target":48,"value":1},
{"source":71,"target":41,"value":1},
{"source":71,"target":25,"value":1},
{"source":72,"target":26,"value":2},
{"source":72,"target":27,"value":1},
{"source":72,"target":11,"value":1},
{"source":73,"target":48,"value":2},
{"source":74,"target":48,"value":2},
{"source":74,"target":73,"value":3},
{"source":75,"target":69,"value":3},
{"source":75,"target":68,"value":3},
{"source":75,"target":25,"value":3},
{"source":75,"target":48,"value":1},
{"source":75,"target":41,"value":1},
{"source":75,"target":70,"value":1},
{"source":75,"target":71,"value":1},
{"source":76,"target":64,"value":1},
{"source":76,"target":65,"value":1},
{"source":76,"target":66,"value":1},
{"source":76,"target":63,"value":1},
{"source":76,"target":62,"value":1},
{"source":76,"target":48,"value":1},
{"source":76,"target":58,"value":1}
]
}
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment