mkhatib/geo.js

## geo.js
/**
* Generates number of random geolocation points given a center and a radius.
* @param  {Object} center A JS object with lat and lng attributes.
* @param  {number} radius Radius in meters.
* @param {number} count Number of points to generate.
* @return {array} Array of Objects with lat and lng attributes.
*/
function generateRandomPoints(center, radius, count) {
  var points = [];
  for (var i=0; i<count; i++) {
    points.push(generateRandomPoint(center, radius));
  }
  return points;
}


/**
* Generates number of random geolocation points given a center and a radius.
* Reference URL: http://goo.gl/KWcPE.
* @param  {Object} center A JS object with lat and lng attributes.
* @param  {number} radius Radius in meters.
* @return {Object} The generated random points as JS object with lat and lng attributes.
*/
function generateRandomPoint(center, radius) {
  var x0 = center.lng;
  var y0 = center.lat;
  // Convert Radius from meters to degrees.
  var rd = radius/111300;

  var u = Math.random();
  var v = Math.random();

  var w = rd * Math.sqrt(u);
  var t = 2 * Math.PI * v;
  var x = w * Math.cos(t);
  var y = w * Math.sin(t);

  var xp = x/Math.cos(y0);

  // Resulting point.
  return {'lat': y+y0, 'lng': xp+x0};
}


// Usage Example.
// Generates 100 points that is in a 1km radius from the given lat and lng point.
var randomGeoPoints = generateRandomPoints({'lat':24.23, 'lng':23.12}, 1000, 100);
	/**
	* Generates number of random geolocation points given a center and a radius.
	* @param {Object} center A JS object with lat and lng attributes.
	* @param {number} radius Radius in meters.
	* @param {number} count Number of points to generate.
	* @return {array} Array of Objects with lat and lng attributes.
	*/
	function generateRandomPoints(center, radius, count) {
	var points = [];
	for (var i=0; i<count; i++) {
	points.push(generateRandomPoint(center, radius));
	}
	return points;
	}


	/**
	* Generates number of random geolocation points given a center and a radius.
	* Reference URL: http://goo.gl/KWcPE.
	* @param {Object} center A JS object with lat and lng attributes.
	* @param {number} radius Radius in meters.
	* @return {Object} The generated random points as JS object with lat and lng attributes.
	*/
	function generateRandomPoint(center, radius) {
	var x0 = center.lng;
	var y0 = center.lat;
	// Convert Radius from meters to degrees.
	var rd = radius/111300;

	var u = Math.random();
	var v = Math.random();

	var w = rd * Math.sqrt(u);
	var t = 2 * Math.PI * v;
	var x = w * Math.cos(t);
	var y = w * Math.sin(t);

	var xp = x/Math.cos(y0);

	// Resulting point.
	return {'lat': y+y0, 'lng': xp+x0};
	}


	// Usage Example.
	// Generates 100 points that is in a 1km radius from the given lat and lng point.
	var randomGeoPoints = generateRandomPoints({'lat':24.23, 'lng':23.12}, 1000, 100);