mbostock · June 21, 2023 17:50 · slngod · Jun 14, 2018
diff --git a/.block b/.block
 license: gpl-3.0
 redirect: https://observablehq.com/@d3/zoomable-map-tiles
diff --git a/README.md b/README.md
diff --git a/d3.geo.tile.min.js b/d3.geo.tile.min.js
 d3.geo.tile=function(){function t(){var t=Math.max(Math.log(n)/Math.LN2-8,0),h=Math.round(t+e),o=Math.pow(2,t-h+8),u=[(r[0]-n/2)/o,(r[1]-n/2)/o],l=[],c=d3.range(Math.max(0,Math.floor(-u[0])),Math.max(0,Math.ceil(a[0]/o-u[0]))),M=d3.range(Math.max(0,Math.floor(-u[1])),Math.max(0,Math.ceil(a[1]/o-u[1])));return M.forEach(function(t){c.forEach(function(a){l.push([a,t,h])})}),l.translate=u,l.scale=o,l}var a=[960,500],n=256,r=[a[0]/2,a[1]/2],e=0;return t.size=function(n){return arguments.length?(a=n,t):a},t.scale=function(a){return arguments.length?(n=a,t):n},t.translate=function(a){return arguments.length?(r=a,t):r},t.zoomDelta=function(a){return arguments.length?(e=+a,t):e},t};
diff --git a/index.html b/index.html
 <!DOCTYPE html>
 <meta charset="utf-8">
 <style>

 body {
  margin: 0;
 }

 .map {
  position: relative;
  overflow: hidden;
 }

 .layer {
  position: absolute;
 }

 .tile {
  pointer-events: none;
  position: absolute;
  width: 256px;
  height: 256px;
 }

 .info {
  position: absolute;
  bottom: 10px;
  left: 10px;
 }

 </style>
 <body>
 <script src="//d3js.org/d3.v3.min.js"></script>
 <script src="d3.geo.tile.min.js"></script>
 <script>

 var width = Math.max(960, window.innerWidth),
    height = Math.max(500, window.innerHeight),
    prefix = prefixMatch(["webkit", "ms", "Moz", "O"]);

 var tile = d3.geo.tile()
    .size([width, height]);

 var projection = d3.geo.mercator();

 var zoom = d3.behavior.zoom()
    .scale(1 << 12)
    .scaleExtent([1 << 9, 1 << 23])
    .translate([width / 2, height / 2])
    .on("zoom", zoomed);

 var map = d3.select("body").append("div")
    .attr("class", "map")
    .style("width", width + "px")
    .style("height", height + "px")
    .call(zoom)
    .on("mousemove", mousemoved);

 var layer = map.append("div")
    .attr("class", "layer");

 var info = map.append("div")
    .attr("class", "info");

 zoomed();

 function zoomed() {
  var tiles = tile
      .scale(zoom.scale())
      .translate(zoom.translate())
      ();

  projection
      .scale(zoom.scale() / 2 / Math.PI)
      .translate(zoom.translate());

  var image = layer
      .style(prefix + "transform", matrix3d(tiles.scale, tiles.translate))
    .selectAll(".tile")
      .data(tiles, function(d) { return d; });

  image.exit()
      .remove();

  image.enter().append("img")
      .attr("class", "tile")
      .attr("src", function(d) { return "http://" + ["a", "b", "c"][Math.random() * 3 | 0] + ".tile.openstreetmap.org/" + d[2] + "/" + d[0] + "/" + d[1] + ".png"; })
      .style("left", function(d) { return (d[0] << 8) + "px"; })
      .style("top", function(d) { return (d[1] << 8) + "px"; });
 }

 function mousemoved() {
  info.text(formatLocation(projection.invert(d3.mouse(this)), zoom.scale()));
 }

 function matrix3d(scale, translate) {
  var k = scale / 256, r = scale % 1 ? Number : Math.round;
  return "matrix3d(" + [k, 0, 0, 0, 0, k, 0, 0, 0, 0, k, 0, r(translate[0] * scale), r(translate[1] * scale), 0, 1 ] + ")";
 }

 function prefixMatch(p) {
  var i = -1, n = p.length, s = document.body.style;
  while (++i < n) if (p[i] + "Transform" in s) return "-" + p[i].toLowerCase() + "-";
  return "";
 }

 function formatLocation(p, k) {
  var format = d3.format("." + Math.floor(Math.log(k) / 2 - 2) + "f");
  return (p[1] < 0 ? format(-p[1]) + "°S" : format(p[1]) + "°N") + " "
       + (p[0] < 0 ? format(-p[0]) + "°W" : format(p[0]) + "°E");
 }

 </script>
diff --git a/thumbnail.png b/thumbnail.png
	license: gpl-3.0
	redirect: https://observablehq.com/@d3/zoomable-map-tiles
	<!DOCTYPE html>
	<meta charset="utf-8">
	<style>

	body {
	margin: 0;
	}

	.map {
	position: relative;
	overflow: hidden;
	}

	.layer {
	position: absolute;
	}

	.tile {
	pointer-events: none;
	position: absolute;
	width: 256px;
	height: 256px;
	}

	.info {
	position: absolute;
	bottom: 10px;
	left: 10px;
	}

	</style>
	<body>
	<script src="//d3js.org/d3.v3.min.js"></script>
	<script src="d3.geo.tile.min.js"></script>
	<script>

	var width = Math.max(960, window.innerWidth),
	height = Math.max(500, window.innerHeight),
	prefix = prefixMatch(["webkit", "ms", "Moz", "O"]);

	var tile = d3.geo.tile()
	.size([width, height]);

	var projection = d3.geo.mercator();

	var zoom = d3.behavior.zoom()
	.scale(1 << 12)
	.scaleExtent([1 << 9, 1 << 23])
	.translate([width / 2, height / 2])
	.on("zoom", zoomed);

	var map = d3.select("body").append("div")
	.attr("class", "map")
	.style("width", width + "px")
	.style("height", height + "px")
	.call(zoom)
	.on("mousemove", mousemoved);

	var layer = map.append("div")
	.attr("class", "layer");

	var info = map.append("div")
	.attr("class", "info");

	zoomed();

	function zoomed() {
	var tiles = tile
	.scale(zoom.scale())
	.translate(zoom.translate())
	();

	projection
	.scale(zoom.scale() / 2 / Math.PI)
	.translate(zoom.translate());

	var image = layer
	.style(prefix + "transform", matrix3d(tiles.scale, tiles.translate))
	.selectAll(".tile")
	.data(tiles, function(d) { return d; });

	image.exit()
	.remove();

	image.enter().append("img")
	.attr("class", "tile")
	.attr("src", function(d) { return "http://" + ["a", "b", "c"][Math.random() * 3 \| 0] + ".tile.openstreetmap.org/" + d[2] + "/" + d[0] + "/" + d[1] + ".png"; })
	.style("left", function(d) { return (d[0] << 8) + "px"; })
	.style("top", function(d) { return (d[1] << 8) + "px"; });
	}

	function mousemoved() {
	info.text(formatLocation(projection.invert(d3.mouse(this)), zoom.scale()));
	}

	function matrix3d(scale, translate) {
	var k = scale / 256, r = scale % 1 ? Number : Math.round;
	return "matrix3d(" + [k, 0, 0, 0, 0, k, 0, 0, 0, 0, k, 0, r(translate[0] * scale), r(translate[1] * scale), 0, 1 ] + ")";
	}

	function prefixMatch(p) {
	var i = -1, n = p.length, s = document.body.style;
	while (++i < n) if (p[i] + "Transform" in s) return "-" + p[i].toLowerCase() + "-";
	return "";
	}

	function formatLocation(p, k) {
	var format = d3.format("." + Math.floor(Math.log(k) / 2 - 2) + "f");
	return (p[1] < 0 ? format(-p[1]) + "°S" : format(p[1]) + "°N") + " "
	+ (p[0] < 0 ? format(-p[0]) + "°W" : format(p[0]) + "°E");
	}

	</script>