AMD加载

这里的例子使用requirejs。因为无论是D3还是TopoJSON都支持AMD模式加载。
我们这里将使用RequireJS的shim配置

创建html

<body>
  <canvas id='globe' width='500' height='500'></canavs>
  <script src='//cdnjs.cloudflare.com/ajax/libs/require.js/2.1.9/require.min.js'
    data-main='/app.js'></script>
</body>

编写app.js

requirejs.config({
  // Tell RequireJS to use `window.d3` and `window.topojson`
  // for those libraries, respectively
  shim: {
    d3: { exports: 'd3' },
    topojson: { exports: 'topojson' }
  },
  paths: {
    'd3': 'path/to/d3.v3.min',
    'topojson': 'path/to/topojson.v1.min'
  }
});

requirejs(['planetaryjs'], function(planetaryjs) {
  // Use Planetary.js here
});