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HTML Settings

Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

              <canvas width="960" height="600"></canvas>

  Blog post:
  <a href="" target="_blank">
    "Get Started Creating D3 Maps"

  SVG version:
  <a href="" target="_blank">

<script src=""></script>
<script src=""></script>
              body {
  margin: 5px;
  text-align: center;
  background-color: #007da4;

canvas {
  width: calc(100vmin - 10px);
  outline: 1px solid white;

p, a {
  color: white;
  font-family: sans-serif;
  font-size: 0.8rem;

              // make D3 aware of the <canvas> element in the HTML
var canvas ="canvas");

var ctx = canvas.node().getContext("2d");

// get <canvas> width and height from HTML instead of hard-coding values
var canvasWidth = +canvas.attr("width"),
  canvasHeight = +canvas.attr("height");

// define the map projection
// we're going from spherical latitude/longitude coordinates to a flat map
var projection = d3
  // use Mercator for now, sigh, because of web map ubiquity...
  // shift the projection translation offset to half of the parent <canvas> width and height
  .translate([canvasWidth / 2, canvasHeight / 2])
  // [0, 0] is redundant, but you could change the initial center [longitude, latitude]
  .center([0, 0])
  // [0, 0, 0] is also redundant, but you can change the rotation along 3 axes
  // this property is really fun, so experiment with different values!
  .rotate([0, 0, 0])
  // set an initial scale value
  .scale(canvasWidth / (2 * Math.PI));

// NOTE: if you want to skip setting the translate and scale values
// and instead zoom out to the whole world, you can just use this shortcut:
// projection.fitSize([canvasWidth, canvasHeight], {
//   type: "Sphere"
// });

// "d3.geoPath" helps convert from geojson coordinates to <svg> or <canvas> drawing instructions
// it needs to know about the projection that was defined above
// and the <canvas> 2d rendering context

// I like to refer to it as a "geographic path generator" throughout the code
var geoPathGenerator = d3

// request publicly available and hosted world topojson data,
// convert it to geojson,
// and then draw it in the <canvas>
  .then(function(loadedTopoJson) {
    // use the concept of a topojson "mesh" to convert topojson
    // to a single, efficient geojson geometry
    var geoJson = topojson.mesh(

    // and then draw the single geojson representing all country polygons
    // by giving explicit instructions to the <canvas> 2d rendering context
    ctx.strokeStyle = "white";
    ctx.lineWidth = 1;
    ctx.lineJoin = "round";
    ctx.lineCap = "round";

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