Skip to content

Instantly share code, notes, and snippets.

@almccon
Last active March 31, 2018 03:41
Show Gist options
  • Save almccon/95cd8ca33304ebc59779f8536ee77688 to your computer and use it in GitHub Desktop.
Save almccon/95cd8ca33304ebc59779f8536ee77688 to your computer and use it in GitHub Desktop.
Vienna and Bellingham
license: mit

Using an orthographic projection to overlay the city of Bellingham, Washington with Vienna, Austria. The two maps are drawn with the "multiply" blend mode, so overlapping areas become blue.

All data © OpenStreetMap contributors

Display the source blob
Display the rendered blob
Raw
Loading
Sorry, something went wrong. Reload?
Sorry, we cannot display this file.
Sorry, this file is invalid so it cannot be displayed.
Display the source blob
Display the rendered blob
Raw
Loading
Sorry, something went wrong. Reload?
Sorry, we cannot display this file.
Sorry, this file is invalid so it cannot be displayed.
name lon lat
vienna 16.379241943359375 48.211404849620486
<!DOCTYPE html>
<meta charset="utf-8">
<style>
body {
background: #fff;
font-family: Helvetica, Arial, sans-serif;
font-size: small;
}
</style>
<body>
<script src="//d3js.org/d3.v4.min.js"></script>
<script src="//d3js.org/topojson.v1.min.js"></script>
<script src="//d3js.org/d3-queue.v3.min.js"></script>
<script>
var width = 960,
height = 500;
var projection = d3.geoOrthographic()
.scale(1e5)
.translate([width / 2, height / 2])
.clipAngle(90)
.precision(.1);
var path = d3.geoPath()
.projection(projection);
var primaryCoords = [-122.489,48.755];
d3.queue()
.defer(d3.csv,"comparisons.csv")
.defer(d3.json,"bellingham.geojson")
.defer(d3.json,"bellingham_coast.geojson")
.awaitAll(function(error, outerdata) {
var comparisons = outerdata[0];
var primary = outerdata[1];
var primary_coast = outerdata[2];
if (error) throw error;
comparisons
.filter(function(comp) { return ['vienna'].indexOf(comp.name) != -1;})
//.filter(function(comp) { return ['venice_italy','thames','seine','danube','rhine','willamette','rotterdam'].indexOf(comp.name) != -1;})
.forEach(function(comp) {
var svg = d3.select("body").append("svg")
.attr("width", width)
.attr("height", height);
//svg.append("text")
// .attr('x',20)
// .attr('y',20)
// .text(comp.name);
var comparisonCoords = [comp.lon,comp.lat];
d3.json(comp.name + ".geojson", function(error, comp_data) {
if (error) throw error;
d3.json(comp.name + "_coast.geojson", function(error, comp_coast) {
if (error) throw error;
//var comp_data = data[0];
//var comp_coast = data[1];
projection.rotate([-comparisonCoords[0],-comparisonCoords[1]]);
// note, I need to load each feature individually to avoid linestrings
var comp_g = svg.append("g")
.style("mix-blend-mode", "multiply");
comp_g
.selectAll("path")
.data(comp_data.features.filter(d => { return d.geometry.type != 'LineString';}))
.enter()
.append("path")
.attr("d", path)
.attr("stroke", 'none')
.attr("fill", 'cyan')
comp_g.append("path")
.attr("d", path(comp_coast))
.attr("stroke", 'none')
.attr("fill", 'cyan')
projection.rotate([-primaryCoords[0],-primaryCoords[1]]);
var primary_g = svg.append("g")
.style("mix-blend-mode", "multiply");
primary_g
.selectAll("path")
.data(primary.features.filter(d => { return d.geometry.type != 'LineString';}))
.enter()
.append("path")
.attr("d", path)
.attr("stroke", 'none')
.attr("fill", 'magenta')
primary_g.append("path")
.attr("d", path(primary_coast))
.attr("stroke", 'none')
.attr("fill", 'magenta')
});
});
});
});
d3.select(self.frameElement).style("height", height + "px");
</script>
Display the source blob
Display the rendered blob
Raw
Loading
Sorry, something went wrong. Reload?
Sorry, we cannot display this file.
Sorry, this file is invalid so it cannot be displayed.
Display the source blob
Display the rendered blob
Raw
Loading
Sorry, something went wrong. Reload?
Sorry, we cannot display this file.
Sorry, this file is invalid so it cannot be displayed.
Display the source blob
Display the rendered blob
Raw
Loading
Sorry, something went wrong. Reload?
Sorry, we cannot display this file.
Sorry, this file is invalid so it cannot be displayed.
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment