README.md

## README.md

      
          Raw
        
        
              README.md
            
          
    Using zoom transitions with tiles.

  
## index.html
<!DOCTYPE html>
<meta charset="utf-8">
<style>

body {
  margin: 0;
}

#container {
  position: relative;
  overflow: hidden;
}

#map{
	width:100%;
	height:100%;
}

.layer {
  position: absolute;
}

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

.info {
  position: absolute;
  bottom: 0px;
  left: 0px;
	padding: 20px;
	background: #000;
	color: #fff;
	width: 100%;
	z-index: 1000;
}
</style>
<body>
<script src="http://d3js.org/d3.v3.min.js"></script>
<script src="http://d3js.org/d3.geo.tile.v0.min.js"></script>
<div id="canvas">
	<div id="container">
		<div id="map">
			<div class="layer"></div>
		</div>
	</div>
</div>
<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 tiles, image;

var sf = [-122.417, 37.775],
		belowsf = [-122.510962, 37.580284];

var projection = d3.geo.mercator()
		.scale((1 << 18) / 2 / Math.PI)
		.translate([width / 2, height / 2]);

var center = projection(sf);

var map = d3.select("#map");

var layer = d3.select(".layer");

var zoom = d3.behavior.zoom()
  .scale(projection.scale() * 2 * Math.PI)
  .translate([width - center[0], height - center[1]])
   .on("zoom", zoomed);

var canvas = d3.select("#canvas")
		.style("width", width + "px")
		.style("height", height + "px");

var container = d3.select("#container")
    .style("width", width + "px")
    .style("height", height + "px")
    .on("mousemove", mousemoved);

		canvas
			 	.call(zoomTo(sf).event)
					.transition()
					.duration(10000)
					.each(jump);

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

function zoomTo(place) {

  projection = d3.geo.mercator()
		.scale((1 << 18) / 2 / Math.PI)
		.translate([width / 2, height / 2])

  center = projection(place);

return zoom
  .scale(projection.scale() * 2 * Math.PI)
  .translate([width - center[0], height - center[1]]);

	//	zoomed();

}


function jump() {
  var t = d3.select(this);
		 	(function repeat() {
		  t = t.transition()
		  .call(zoomTo(belowsf).event)
		  .transition()
		  .call(zoomTo(sf).event)
		  .each("end", repeat);
  })();
}


//zoomed();

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


function zoomed() {


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

     tiles = tile
      .scale(zoom.scale())
      .translate(zoom.translate())
      ();

  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] + ".basemaps.cartocdn.com/light_all/" + 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 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>
</body>
</html>

## thumbnail.png

      
          Raw
        
        
              thumbnail.png