利用d3.js绘制中国地图

d3.js是一个比較强的数据可视化js工具。

利用它画了一幅中国地图，例如以下图所看到的：

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源代码例如以下：

<!DOCTYPE html>
<html>
  <head>
    <script type="text/javascript" src="d3.js"></script>
    <script type="text/javascript" src="d3.csv.js"></script>
    <script type="text/javascript" src="d3.geo.js"></script>
    <script type="text/javascript" src="d3.geom.js"></script>
  </head>
  <body>
  <div id='map'></div>

    <script type="text/javascript">

var w = 1280,
    h = 800;

var projection = d3.geo.azimuthal()//  //mercator()
    //.mode("equidistant")
    //.origin([-98, 38])
    //.scale(1400)
    //.translate([640, 360]);
	.mode("equidistant")
    .origin([107, 32])///???
    .scale(1000)
    .translate([w/2, h/2]);

var path = d3.geo.path()
    .projection(projection);

var svg = d3.select("#map").insert("svg:svg")
	//.append('svg')//
    .attr("width", w)
    .attr("height", h);

var states = svg.append("svg:g")
    .attr("id", "states");

var circles = svg.append("svg:g")
    .attr("id", "circles");

var texts = svg.append("svg:g")
	.attr("id", "texts");

var cells = svg.append("svg:g")
    .attr("id", "cells");

d3.json("china.json", function(collection) {
  states.selectAll("path")
      .data(collection.features)
    .enter().append("svg:path")
      .attr("d", path)
	  .attr('fill','#ddd')
	  .attr('stroke','#222')
	  .attr('stroke-width','1px')
	  ;
});
var positions=[];
d3.csv('china-cities.csv',function(c){
	circles.selectAll("circle")
        .data(c)
        .enter().append("svg:circle")
        .attr("cx", function(d,i){return projection([d.lon,d.lat])[0];})
        .attr("cy",function(d,i){return projection([d.lon,d.lat])[1];})
		.attr("r", 3)
		.attr('fill','red');

	texts.selectAll("text")
		.data(c)
		.enter().append("svg:text")
		.text(function(d){return d.city;})
		.attr("x", function(d){
			var local=projection([d.lon,d.lat]);
			if(d.lon=='113.5575191')//处理澳门
			return (local[0]-30);
			else return local[0];})
        .attr("y",function(d){
			var local=projection([d.lon,d.lat]);
			if(d.lat=='39.1439299') return (local[1]+10);//处理天津
			else return local[1];
			})
		.attr('fill','#000')
		.attr('font-size','14px')
		;
});

    </script>
  </body>
</html>