{
  "$schema": "https://vega.github.io/schema/vega/v5.json",
  "padding": 10,
  "width": 450,
  "height": 450,
  "autosize": "none",

  "signals": [
    {
      "name": "quakeSize", "value": 6,
      "bind": {"input": "range", "min": 0, "max": 12}
    },
    {
      "name": "rotate0", "value": 90,
      "bind": {"input": "range", "min": -180, "max": 180}
    },
    {
      "name": "rotate1", "value": 0,
      "bind": {"input": "range", "min": -180, "max": 180}
    }
  ],

  "data": [
    {
      "name": "sphere",
      "values": [
        {"type": "Sphere"}
      ]
    },
    {
      "name": "world",
      "url": "data/world-110m.json",
      "format": {
        "type": "topojson",
        "feature": "countries"
      }
    },
    {
      "name": "earthquakes",
      "url": "data/earthquakes.json",
      "format": {
        "type": "json",
        "property": "features"
      }
    }
  ],

  "projections": [
    {
      "name": "projection",
      "scale": 225,
      "type": "orthographic",
      "translate": {"signal": "[width/2, height/2]"},
      "rotate": [{"signal": "rotate0"}, {"signal": "rotate1"}, 0]
    }
  ],

  "scales": [
    {
      "name": "size",
      "type": "sqrt",
      "domain": [0, 100],
      "range": [0, {"signal": "quakeSize"}]
    }
  ],

  "marks": [
    {
      "type": "shape",
      "from": {"data": "sphere"},
      "encode": {
        "update": {
          "fill": {"value": "aliceblue"},
          "stroke": {"value": "black"},
          "strokeWidth": {"value": 1.5}
        }
      },
      "transform": [
        {
          "type": "geoshape",
          "projection": "projection"
        }
      ]
    },
    {
      "type": "shape",
      "from": {"data": "world"},
      "encode": {
        "update": {
          "fill": {"value": "mintcream"},
          "stroke": {"value": "black"},
          "strokeWidth": {"value": 0.35}
        }
      },
      "transform": [
        {
          "type": "geoshape",
          "projection": "projection"
        }
      ]
    },
    {
      "type": "shape",
      "from": {"data": "earthquakes"},
      "encode": {
        "update": {
          "opacity": {"value": 0.25},
          "fill": {"value": "red"}
        }
      },
      "transform": [
        {
          "type": "geoshape",
          "projection": "projection",
          "pointRadius": {"expr": "scale('size', exp(datum.properties.mag))"}
        }
      ]
    }
  ]
}