This example is an extension of Mike Bostock’s tutorial Lets Make a Map that implements automatic label placement using collision detection. This is a proof of concept more than anything, not polished in any way.
-
-
Save git-ashish/c09a72ebfef66f55fd040400c47d2626 to your computer and use it in GitHub Desktop.
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> | |
| <html lang="en"> | |
| <head> | |
| <meta charset="UTF-8"/> | |
| <title>Automatic Label Placement</title> | |
| <script src="http://d3js.org/d3.v3.min.js"></script> | |
| <script src="http://d3js.org/topojson.v1.min.js"></script> | |
| <style> | |
| .subunit.SCT { fill: #ddc; } | |
| .subunit.WLS { fill: #cdd; } | |
| .subunit.NIR { fill: #cdc; } | |
| .subunit.ENG { fill: #dcd; } | |
| .subunit.IRL, | |
| .subunit-label.IRL { | |
| display: none; | |
| } | |
| .subunit-boundary { | |
| fill: none; | |
| stroke: #777; | |
| stroke-dasharray: 2,2; | |
| stroke-linejoin: round; | |
| } | |
| .subunit-boundary.IRL { | |
| stroke: #aaa; | |
| } | |
| .place, | |
| .place-label { | |
| fill: #444; | |
| } | |
| text { | |
| font-family: "Helvetica Neue", Helvetica, Arial, sans-serif; | |
| font-size: 24px; | |
| pointer-events: none; | |
| } | |
| </style> | |
| </head> | |
| <body> | |
| <script> | |
| var width = 960, | |
| height = 1160; | |
| var projection = d3.geo.albers() | |
| .center([0, 55.4]) | |
| .rotate([4.4, 0]) | |
| .parallels([50, 60]) | |
| .scale(1200 * 5) | |
| .translate([width / 2, height / 2]); | |
| var path = d3.geo.path() | |
| .projection(projection) | |
| .pointRadius(2); | |
| var svg = d3.select("body").append("svg") | |
| .attr("width", width) | |
| .attr("height", height); | |
| d3.json("uk.json", function(error, uk) { | |
| var subunits = topojson.feature(uk, uk.objects.subunits), | |
| places = topojson.feature(uk, uk.objects.places); | |
| svg.selectAll(".subunit") | |
| .data(subunits.features) | |
| .enter().append("path") | |
| .attr("class", function(d) { return "subunit " + d.id; }) | |
| .attr("d", path); | |
| svg.append("path") | |
| .datum(topojson.mesh(uk, uk.objects.subunits, function(a, b) { return a !== b && a.id !== "IRL"; })) | |
| .attr("d", path) | |
| .attr("class", "subunit-boundary"); | |
| svg.append("path") | |
| .datum(topojson.mesh(uk, uk.objects.subunits, function(a, b) { return a === b && a.id === "IRL"; })) | |
| .attr("d", path) | |
| .attr("class", "subunit-boundary IRL"); | |
| svg.append("path") | |
| .datum(places) | |
| .attr("d", path) | |
| .attr("class", "place"); | |
| svg.selectAll(".place-label") | |
| .data(topojson.feature(uk, uk.objects.places).features) | |
| .enter().append("text") | |
| .attr("class", "place-label") | |
| .attr("transform", function(d) { return "translate(" + projection(d.geometry.coordinates) + ")"; }) | |
| .attr("x", function(d) { return d.geometry.coordinates[0] > -1 ? 6 : -6; }) | |
| .attr("dy", ".35em") | |
| .style("text-anchor", function(d) { return d.geometry.coordinates[0] > -1 ? "start" : "end"; }) | |
| .text(function(d) { return d.properties.name; }); | |
| arrangeLabels(); | |
| }); | |
| function arrangeLabels() { | |
| var move = 1; | |
| while(move > 0) { | |
| move = 0; | |
| svg.selectAll(".place-label") | |
| .each(function() { | |
| var that = this, | |
| a = this.getBoundingClientRect(); | |
| svg.selectAll(".place-label") | |
| .each(function() { | |
| if(this != that) { | |
| var b = this.getBoundingClientRect(); | |
| if((Math.abs(a.left - b.left) * 2 < (a.width + b.width)) && | |
| (Math.abs(a.top - b.top) * 2 < (a.height + b.height))) { | |
| // overlap, move labels | |
| var dx = (Math.max(0, a.right - b.left) + | |
| Math.min(0, a.left - b.right)) * 0.01, | |
| dy = (Math.max(0, a.bottom - b.top) + | |
| Math.min(0, a.top - b.bottom)) * 0.02, | |
| tt = d3.transform(d3.select(this).attr("transform")), | |
| to = d3.transform(d3.select(that).attr("transform")); | |
| move += Math.abs(dx) + Math.abs(dy); | |
| to.translate = [ to.translate[0] + dx, to.translate[1] + dy ]; | |
| tt.translate = [ tt.translate[0] - dx, tt.translate[1] - dy ]; | |
| d3.select(this).attr("transform", "translate(" + tt.translate + ")"); | |
| d3.select(that).attr("transform", "translate(" + to.translate + ")"); | |
| a = this.getBoundingClientRect(); | |
| } | |
| } | |
| }); | |
| }); | |
| } | |
| } | |
| </script> | |
| </body> | |
| </html> |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment