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D3JS GeoJSON Scale and Translate
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| <!DOCTYPE html> | |
| <html lang="en"> | |
| <head> | |
| <meta charset="utf-8"> | |
| <title>D3 NYC Geo Test</title> | |
| </head> | |
| <style type="text/css"> | |
| body { | |
| margin: 0; | |
| padding: 0; | |
| width: 100%; | |
| height: 100%; | |
| } | |
| </style> | |
| <body> | |
| <script src="http://d3js.org/d3.v3.min.js"></script> | |
| <script type="text/javascript"> | |
| /* code reused from the following stackoverflow question: | |
| http://stackoverflow.com/questions/14492284/center-a-map-in-d3-given-a-geojson-object */ | |
| var width = 900, | |
| height = 900; | |
| var svg = d3.select("body").append("svg") | |
| .attr("width", width) | |
| .attr("height", height) | |
| .attr("class", "svg"); | |
| // load geojson and do stuff in a callback function... | |
| d3.json("nyc_coastline.json", function(error, data){ | |
| // console.log the data | |
| console.log(data); | |
| // create a unit projection | |
| var projection = d3.geo.albers() | |
| .scale(1) | |
| .translate([0,0]); | |
| // create a path generator. | |
| var path = d3.geo.path() | |
| .projection(projection); | |
| // compute bounds of a point of interest, then derive scale and translate | |
| var b = path.bounds(data), | |
| s = .95 / Math.max((b[1][0] - b[0][0]) / width, (b[1][1] - b[0][1]) / height), | |
| t = [(width - s * (b[1][0] + b[0][0])) / 2, (height - s * (b[1][1] + b[0][1])) / 2]; | |
| // update the projection to use computed scale and translate.... | |
| projection | |
| .scale(s) | |
| .translate(t); | |
| // calculate and draw a bounding box for the geojson | |
| svg.append("rect") | |
| .attr('width', width) | |
| .attr('height', height) | |
| .style('stroke', 'black') | |
| .style('fill', 'orange'); | |
| // draw the svg of both the geojson and bounding box | |
| svg.selectAll("path").data(data.features).enter().append("path") | |
| .attr("d", path) | |
| .style("fill", "red") | |
| .style("stroke-width", "1") | |
| .style("stroke", "blue") | |
| }); | |
| </script> | |
| </body> | |
| </html> |
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How do I translate this map?
let path = d3.geoPath()
...
No projection.