A comparison of 41 map projections by four different types of distortion. Lower is better. Data transcribed from the Natural Earth Projection.
xxxxxxxxxx
<meta charset="utf-8">
<title>Map Projections</title>
<style>
svg {
font: 10px sans-serif;
}
.background path {
fill: none;
stroke: none;
stroke-width: 20px;
pointer-events: stroke;
}
.foreground path {
fill: none;
stroke: steelblue;
stroke-width: 1.5px;
}
.axis .title {
font-size: 11px;
font-weight: bold;
text-transform: uppercase;
}
.axis line,
.axis path {
fill: none;
stroke: #000;
shape-rendering: crispEdges;
}
.label {
-webkit-transition: fill 125ms linear;
}
.active .label:not(.inactive) {
font-weight: bold;
}
.label.inactive {
fill: #ccc;
}
.foreground path.inactive {
stroke: #ccc;
stroke-opacity: .5;
stroke-width: 1px;
}
</style>
<body>
<script src="//d3js.org/d3.v3.min.js"></script>
<script>
var margin = {top: 30, right: 40, bottom: 20, left: 200},
width = 960 - margin.left - margin.right,
height = 500 - margin.top - margin.bottom;
var dimensions = [
{
name: "name",
scale: d3.scale.ordinal().rangePoints([0, height]),
type: String
},
{
name: "Acc. 40º 150%",
scale: d3.scale.linear().range([0, height]),
type: Number
},
{
name: "Scale",
scale: d3.scale.linear().range([height, 0]),
type: Number
},
{
name: "Areal",
scale: d3.scale.sqrt().range([height, 0]),
type: Number
},
{
name: "Angular",
scale: d3.scale.linear().range([height, 0]),
type: Number
}
];
var x = d3.scale.ordinal()
.domain(dimensions.map(function(d) { return d.name; }))
.rangePoints([0, width]);
var line = d3.svg.line()
.defined(function(d) { return !isNaN(d[1]); });
var yAxis = d3.svg.axis()
.orient("left");
var svg = d3.select("body").append("svg")
.attr("width", width + margin.left + margin.right)
.attr("height", height + margin.top + margin.bottom)
.append("g")
.attr("transform", "translate(" + margin.left + "," + margin.top + ")");
var dimension = svg.selectAll(".dimension")
.data(dimensions)
.enter().append("g")
.attr("class", "dimension")
.attr("transform", function(d) { return "translate(" + x(d.name) + ")"; });
d3.tsv("projections.tsv", function(error, data) {
if (error) throw error;
dimensions.forEach(function(dimension) {
dimension.scale.domain(dimension.type === Number
? d3.extent(data, function(d) { return +d[dimension.name]; })
: data.map(function(d) { return d[dimension.name]; }).sort());
});
svg.append("g")
.attr("class", "background")
.selectAll("path")
.data(data)
.enter().append("path")
.attr("d", draw);
svg.append("g")
.attr("class", "foreground")
.selectAll("path")
.data(data)
.enter().append("path")
.attr("d", draw);
dimension.append("g")
.attr("class", "axis")
.each(function(d) { d3.select(this).call(yAxis.scale(d.scale)); })
.append("text")
.attr("class", "title")
.attr("text-anchor", "middle")
.attr("y", -9)
.text(function(d) { return d.name; });
// Rebind the axis data to simplify mouseover.
svg.select(".axis").selectAll("text:not(.title)")
.attr("class", "label")
.data(data, function(d) { return d.name || d; });
var projection = svg.selectAll(".axis text,.background path,.foreground path")
.on("mouseover", mouseover)
.on("mouseout", mouseout);
function mouseover(d) {
svg.classed("active", true);
projection.classed("inactive", function(p) { return p !== d; });
projection.filter(function(p) { return p === d; }).each(moveToFront);
}
function mouseout(d) {
svg.classed("active", false);
projection.classed("inactive", false);
}
function moveToFront() {
this.parentNode.appendChild(this);
}
});
function draw(d) {
return line(dimensions.map(function(dimension) {
return [x(dimension.name), dimension.scale(d[dimension.name])];
}));
}
</script>
https://d3js.org/d3.v3.min.js