Skip to content

Instantly share code, notes, and snippets.

@li01012
Last active April 6, 2017 18:24
Show Gist options
  • Save li01012/ce2daa1d20b69ca806ce8aff3298cd6f to your computer and use it in GitHub Desktop.
Save li01012/ce2daa1d20b69ca806ce8aff3298cd6f to your computer and use it in GitHub Desktop.
assignment9
license: mit
<!DOCTYPE html>
<meta charset="utf-8">
<style>
body {
margin: 7;
}
path {
fill: none;
stroke: black;
stroke-width: 0.5px;
}
path.quake {
fill: blue;
}
</style>
<svg></svg>
<script src="//d3js.org/d3.v4.min.js"></script>
<script src="//d3js.org/d3-tile.v0.0.min.js"></script>
<script src="//d3js.org/topojson.v1.min.js"></script>
<script>
var pi = Math.PI,
tau = 2 * pi;
var width = Math.max(860, window.innerWidth),
height = Math.max(600, window.innerHeight);
var data; // declare a global variable
var projection = d3.geoMercator()
.scale(1 / tau)
.translate([0, 0]);
var path = d3.geoPath()
.projection(projection);
var tile = d3.tile()
.size([width, height]);
var zoom = d3.zoom()
.scaleExtent([1 << 10, 1 << 16])
.on("zoom", zoomed);
var svg = d3.select("svg")
.attr("width", width)
.attr("height", height);
var raster = svg.append("g");
var vector = svg.append("path");
d3.json("https://gist.githubusercontent.com/mbostock/4090846/raw/d534aba169207548a8a3d670c9c2cc719ff05c47/us.json", function(error, us) {
if (error) throw error;
vector
.datum(topojson.mesh(us, us.objects.states));
var center = projection([-98.5, 39.5]);
svg
.call(zoom)
.call(zoom.transform, d3.zoomIdentity
.translate(width / 2, height / 2)
.scale(1 << 12.8)
.translate(-center[0], -center[1]));
});
function zoomed() {
var transform = d3.event.transform;
var tiles = tile
.scale(transform.k)
.translate([transform.x, transform.y])
();
projection
.scale(transform.k / tau)
.translate([transform.x, transform.y]);
vector
.attr("d", path);
var image = raster
.attr("transform", stringify(tiles.scale, tiles.translate))
.selectAll("image")
.data(tiles, function(d) { return d; });
image.enter().append("image")
.attr("xlink:href", function(d) { return "http://" + "abc"[d[1] % 3] + ".tile.openstreetmap.org/" + d[2] + "/" + d[0] + "/" + d[1] + ".png"; })
.attr("x", function(d) { return d[0] * 256; })
.attr("y", function(d) { return d[1] * 256; })
.attr("width", 256)
.attr("height", 256);
}
function stringify(scale, translate) {
var k = scale / 256, r = scale % 1 ? Number : Math.round;
return "translate(" + r(translate[0] * scale) + "," + r(translate[1] * scale) + ") scale(" + k + ")";
}
var path = d3.geoPath()
.projection(projection);
// Send earthquake data to function "plotQuakes"
var usgs = "https://earthquake.usgs.gov/earthquakes/feed/v1.0/summary/all_week.geojson";
// Topojson for US states
var url = "https://umbcvis.github.io/classes/class-03/us.json"
d3.json(url, plotStates);
d3.json(usgs, plotQuakes);
function plotStates(error, json) {
data = json.objects.us.geometries.map(function(d) { return topojson.feature(json, d); })
}
// Plot the earthquake data
function plotQuakes(error, json) {
if (error) return console.log(error);
data = json;
var features = json.features;
var layer2 = svg.append("g");
layer2.selectAll("path.quake")
.data(features)
.enter().append("path")
.attr("class", "quake")
.attr("d", path)
}
function mousemoved() {
info.text(formatLocation(projection.invert(d3.mouse(this)), projection.scale()));
}
</script>
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment