plot earthquake data from USGS - uses WWW module and JSONObject plugin

plotquakes2.js

#pragma strict

// Script to visualize earthquake data in GeoJSON format from USGS
// (http://earthquake.usgs.gov/earthquakes/feed/v1.0/geojson.php)
// Requires the JSONObject plugin from http://wiki.unity3d.com/index.php/JSONObject
// The script should be attached to a model of the Earth such as a sphere
// with a 20 unit diameter.  A prefab to use for marking the quakes should
// be assigned to the variable "prefab" in the Unity editor.

import JSONObject;

public var prefab : GameObject;
public var url = "http://earthquake.usgs.gov/earthquakes/feed/v1.0/summary/4.5_month.geojson";

function Start ()
    {
    var dataurl : WWW = new WWW(url);
    yield dataurl;
    var data = new JSONObject(dataurl.text,-2,false,false);
    var i : int;
    var lat : float;
    var lon : float;
    var mag : float;
    var radius = 10.0;
    for (i=0; i < data["metadata"]["count"].n; i++)
        {
        lon = data["features"][i]["geometry"]["coordinates"][0].n;
        lat = data["features"][i]["geometry"]["coordinates"][1].n;
        mag = data["features"][i]["properties"]["mag"].n;
        Debug.Log("quake at " + lat + " " + lon + ", magnitude " + mag);
        lon = lon * Mathf.Deg2Rad;
        lat = lat * Mathf.Deg2Rad;
        var pos = new Vector3(Mathf.Cos(lon)*Mathf.Cos(lat)*radius, Mathf.Sin(lat)*radius, Mathf.Sin(lon)*Mathf.Cos(lat)*radius);
        var marker = Instantiate(prefab, pos, Quaternion.identity);
        var size = mag*mag/100.0;
        marker.transform.localScale = Vector3(size,size,size);
        marker.transform.parent = transform;
        }
    }