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May 7, 2014 19:09
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(function e(t,n,r){function s(o,u){if(!n[o]){if(!t[o]){var a=typeof require=="function"&&require;if(!u&&a)return a(o,!0);if(i)return i(o,!0);throw new Error("Cannot find module '"+o+"'")}var f=n[o]={exports:{}};t[o][0].call(f.exports,function(e){var n=t[o][1][e];return s(n?n:e)},f,f.exports,e,t,n,r)}return n[o].exports}var i=typeof require=="function"&&require;for(var o=0;o<r.length;o++)s(r[o]);return s})({1:[function(require,module,exports){ | |
var sph = new (require('sphericalmercator'))(), | |
geojsonExtent = require('geojson-extent'); | |
function $(_) { | |
return document.getElementById(_); | |
} | |
$('compute').addEventListener('click', function() { | |
var ext = geojsonExtent(JSON.parse($('geojson').value)); | |
var min = +$('low-zoom').value; | |
var max = +$('high-zoom').value; | |
var sum = 0; | |
for (var i = min; i < max; i++) { | |
var b = sph.xyz(ext, i); | |
sum += (b.maxX - b.minX) * (b.maxY - b.minY); | |
} | |
$('count').innerHTML = sum; | |
}); | |
},{"geojson-extent":2,"sphericalmercator":8}],2:[function(require,module,exports){ | |
var geojsonCoords = require('geojson-coords'), | |
extent = require('extent'); | |
module.exports = function(_) { | |
var bbox = [Infinity, Infinity, -Infinity, -Infinity], | |
ext = extent(), | |
coords = geojsonCoords(_); | |
for (var i = 0; i < coords.length; i++) ext.include(coords[i]); | |
return ext.bbox(); | |
}; | |
},{"extent":3,"geojson-coords":5}],3:[function(require,module,exports){ | |
module.exports = Extent; | |
function Extent() { | |
if (!(this instanceof Extent)) { | |
return new Extent(); | |
} | |
this._bbox = [Infinity, Infinity, -Infinity, -Infinity]; | |
this._valid = false; | |
} | |
Extent.prototype.include = function(ll) { | |
this._valid = true; | |
this._bbox[0] = Math.min(this._bbox[0], ll[0]); | |
this._bbox[1] = Math.min(this._bbox[1], ll[1]); | |
this._bbox[2] = Math.max(this._bbox[2], ll[0]); | |
this._bbox[3] = Math.max(this._bbox[3], ll[1]); | |
return this; | |
}; | |
Extent.prototype.union = function(other) { | |
this._valid = true; | |
this._bbox[0] = Math.min(this._bbox[0], other[0]); | |
this._bbox[1] = Math.min(this._bbox[1], other[1]); | |
this._bbox[2] = Math.max(this._bbox[2], other[2]); | |
this._bbox[3] = Math.max(this._bbox[3], other[3]); | |
return this; | |
}; | |
Extent.prototype.bbox = function() { | |
if (!this._valid) return null; | |
return this._bbox; | |
}; | |
},{}],4:[function(require,module,exports){ | |
module.exports = function flatten(list, depth) { | |
return _flatten(list); | |
function _flatten(list) { | |
if (Array.isArray(list) && list.length && | |
typeof list[0] === 'number') { | |
return [list]; | |
} | |
return list.reduce(function (acc, item) { | |
if (Array.isArray(item) && Array.isArray(item[0])) { | |
return acc.concat(_flatten(item)); | |
} else { | |
acc.push(item); | |
return acc; | |
} | |
}, []); | |
} | |
}; | |
},{}],5:[function(require,module,exports){ | |
var geojsonNormalize = require('geojson-normalize'), | |
geojsonFlatten = require('geojson-flatten'), | |
flatten = require('./flatten'); | |
module.exports = function(_) { | |
if (!_) return []; | |
var normalized = geojsonFlatten(geojsonNormalize(_)), | |
coordinates = []; | |
normalized.features.forEach(function(feature) { | |
if (!feature.geometry) return; | |
coordinates = coordinates.concat(flatten(feature.geometry.coordinates)); | |
}); | |
return coordinates; | |
}; | |
},{"./flatten":4,"geojson-flatten":6,"geojson-normalize":7}],6:[function(require,module,exports){ | |
module.exports = flatten; | |
function flatten(gj, up) { | |
switch ((gj && gj.type) || null) { | |
case 'FeatureCollection': | |
gj.features = gj.features.reduce(function(mem, feature) { | |
return mem.concat(flatten(feature)); | |
}, []); | |
return gj; | |
case 'Feature': | |
return flatten(gj.geometry).map(function(geom) { | |
return { | |
type: 'Feature', | |
properties: JSON.parse(JSON.stringify(gj.properties)), | |
geometry: geom | |
}; | |
}); | |
case 'MultiPoint': | |
return gj.coordinates.map(function(_) { | |
return { type: 'Point', coordinates: _ }; | |
}); | |
case 'MultiPolygon': | |
return gj.coordinates.map(function(_) { | |
return { type: 'Polygon', coordinates: _ }; | |
}); | |
case 'MultiLineString': | |
return gj.coordinates.map(function(_) { | |
return { type: 'LineString', coordinates: _ }; | |
}); | |
case 'GeometryCollection': | |
return gj.geometries; | |
case 'Point': | |
case 'Polygon': | |
case 'LineString': | |
return [gj]; | |
default: | |
return gj; | |
} | |
} | |
},{}],7:[function(require,module,exports){ | |
module.exports = normalize; | |
var types = { | |
Point: 'geometry', | |
MultiPoint: 'geometry', | |
LineString: 'geometry', | |
MultiLineString: 'geometry', | |
Polygon: 'geometry', | |
MultiPolygon: 'geometry', | |
GeometryCollection: 'geometry', | |
Feature: 'feature', | |
FeatureCollection: 'featurecollection' | |
}; | |
/** | |
* Normalize a GeoJSON feature into a FeatureCollection. | |
* | |
* @param {object} gj geojson data | |
* @returns {object} normalized geojson data | |
*/ | |
function normalize(gj) { | |
if (!gj || !gj.type) return null; | |
var type = types[gj.type]; | |
if (!type) return null; | |
if (type === 'geometry') { | |
return { | |
type: 'FeatureCollection', | |
features: [{ | |
type: 'Feature', | |
properties: {}, | |
geometry: gj | |
}] | |
}; | |
} else if (type === 'feature') { | |
return { | |
type: 'FeatureCollection', | |
features: [gj] | |
}; | |
} else if (type === 'featurecollection') { | |
return gj; | |
} | |
} | |
},{}],8:[function(require,module,exports){ | |
var SphericalMercator = (function(){ | |
// Closures including constants and other precalculated values. | |
var cache = {}, | |
EPSLN = 1.0e-10, | |
D2R = Math.PI / 180, | |
R2D = 180 / Math.PI, | |
// 900913 properties. | |
A = 6378137, | |
MAXEXTENT = 20037508.34; | |
// SphericalMercator constructor: precaches calculations | |
// for fast tile lookups. | |
function SphericalMercator(options) { | |
options = options || {}; | |
this.size = options.size || 256; | |
if (!cache[this.size]) { | |
var size = this.size; | |
var c = cache[this.size] = {}; | |
c.Bc = []; | |
c.Cc = []; | |
c.zc = []; | |
c.Ac = []; | |
for (var d = 0; d < 30; d++) { | |
c.Bc.push(size / 360); | |
c.Cc.push(size / (2 * Math.PI)); | |
c.zc.push(size / 2); | |
c.Ac.push(size); | |
size *= 2; | |
} | |
} | |
this.Bc = cache[this.size].Bc; | |
this.Cc = cache[this.size].Cc; | |
this.zc = cache[this.size].zc; | |
this.Ac = cache[this.size].Ac; | |
}; | |
// Convert lon lat to screen pixel value | |
// | |
// - `ll` {Array} `[lon, lat]` array of geographic coordinates. | |
// - `zoom` {Number} zoom level. | |
SphericalMercator.prototype.px = function(ll, zoom) { | |
var d = this.zc[zoom]; | |
var f = Math.min(Math.max(Math.sin(D2R * ll[1]), -0.9999), 0.9999); | |
var x = Math.round(d + ll[0] * this.Bc[zoom]); | |
var y = Math.round(d + 0.5 * Math.log((1 + f) / (1 - f)) * (-this.Cc[zoom])); | |
(x > this.Ac[zoom]) && (x = this.Ac[zoom]); | |
(y > this.Ac[zoom]) && (y = this.Ac[zoom]); | |
//(x < 0) && (x = 0); | |
//(y < 0) && (y = 0); | |
return [x, y]; | |
}; | |
// Convert screen pixel value to lon lat | |
// | |
// - `px` {Array} `[x, y]` array of geographic coordinates. | |
// - `zoom` {Number} zoom level. | |
SphericalMercator.prototype.ll = function(px, zoom) { | |
var g = (px[1] - this.zc[zoom]) / (-this.Cc[zoom]); | |
var lon = (px[0] - this.zc[zoom]) / this.Bc[zoom]; | |
var lat = R2D * (2 * Math.atan(Math.exp(g)) - 0.5 * Math.PI); | |
return [lon, lat]; | |
}; | |
// Convert tile xyz value to bbox of the form `[w, s, e, n]` | |
// | |
// - `x` {Number} x (longitude) number. | |
// - `y` {Number} y (latitude) number. | |
// - `zoom` {Number} zoom. | |
// - `tms_style` {Boolean} whether to compute using tms-style. | |
// - `srs` {String} projection for resulting bbox (WGS84|900913). | |
// - `return` {Array} bbox array of values in form `[w, s, e, n]`. | |
SphericalMercator.prototype.bbox = function(x, y, zoom, tms_style, srs) { | |
// Convert xyz into bbox with srs WGS84 | |
if (tms_style) { | |
y = (Math.pow(2, zoom) - 1) - y; | |
} | |
// Use +y to make sure it's a number to avoid inadvertent concatenation. | |
var ll = [x * this.size, (+y + 1) * this.size]; // lower left | |
// Use +x to make sure it's a number to avoid inadvertent concatenation. | |
var ur = [(+x + 1) * this.size, y * this.size]; // upper right | |
var bbox = this.ll(ll, zoom).concat(this.ll(ur, zoom)); | |
// If web mercator requested reproject to 900913. | |
if (srs === '900913') { | |
return this.convert(bbox, '900913'); | |
} else { | |
return bbox; | |
} | |
}; | |
// Convert bbox to xyx bounds | |
// | |
// - `bbox` {Number} bbox in the form `[w, s, e, n]`. | |
// - `zoom` {Number} zoom. | |
// - `tms_style` {Boolean} whether to compute using tms-style. | |
// - `srs` {String} projection of input bbox (WGS84|900913). | |
// - `@return` {Object} XYZ bounds containing minX, maxX, minY, maxY properties. | |
SphericalMercator.prototype.xyz = function(bbox, zoom, tms_style, srs) { | |
// If web mercator provided reproject to WGS84. | |
if (srs === '900913') { | |
bbox = this.convert(bbox, 'WGS84'); | |
} | |
var ll = [bbox[0], bbox[1]]; // lower left | |
var ur = [bbox[2], bbox[3]]; // upper right | |
var px_ll = this.px(ll, zoom); | |
var px_ur = this.px(ur, zoom); | |
// Y = 0 for XYZ is the top hence minY uses px_ur[1]. | |
var bounds = { | |
minX: Math.floor(px_ll[0] / this.size), | |
minY: Math.floor(px_ur[1] / this.size), | |
maxX: Math.floor((px_ur[0] - 1) / this.size), | |
maxY: Math.floor((px_ll[1] - 1) / this.size) | |
}; | |
if (tms_style) { | |
var tms = { | |
minY: (Math.pow(2, zoom) - 1) - bounds.maxY, | |
maxY: (Math.pow(2, zoom) - 1) - bounds.minY | |
}; | |
bounds.minY = tms.minY; | |
bounds.maxY = tms.maxY; | |
} | |
return bounds; | |
}; | |
// Convert projection of given bbox. | |
// | |
// - `bbox` {Number} bbox in the form `[w, s, e, n]`. | |
// - `to` {String} projection of output bbox (WGS84|900913). Input bbox | |
// assumed to be the "other" projection. | |
// - `@return` {Object} bbox with reprojected coordinates. | |
SphericalMercator.prototype.convert = function(bbox, to) { | |
if (to === '900913') { | |
return this.forward(bbox.slice(0, 2)).concat(this.forward(bbox.slice(2,4))); | |
} else { | |
return this.inverse(bbox.slice(0, 2)).concat(this.inverse(bbox.slice(2,4))); | |
} | |
}; | |
// Convert lon/lat values to 900913 x/y. | |
SphericalMercator.prototype.forward = function(ll) { | |
var xy = [ | |
A * ll[0] * D2R, | |
A * Math.log(Math.tan((Math.PI*0.25) + (0.5 * ll[1] * D2R))) | |
]; | |
// if xy value is beyond maxextent (e.g. poles), return maxextent. | |
(xy[0] > MAXEXTENT) && (xy[0] = MAXEXTENT); | |
(xy[0] < -MAXEXTENT) && (xy[0] = -MAXEXTENT); | |
(xy[1] > MAXEXTENT) && (xy[1] = MAXEXTENT); | |
(xy[1] < -MAXEXTENT) && (xy[1] = -MAXEXTENT); | |
return xy; | |
}; | |
// Convert 900913 x/y values to lon/lat. | |
SphericalMercator.prototype.inverse = function(xy) { | |
return [ | |
(xy[0] * R2D / A), | |
((Math.PI*0.5) - 2.0 * Math.atan(Math.exp(-xy[1] / A))) * R2D | |
]; | |
}; | |
return SphericalMercator; | |
})(); | |
if (typeof module !== 'undefined' && typeof exports !== 'undefined') { | |
module.exports = exports = SphericalMercator; | |
} | |
},{}]},{},[1]) |
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<!DOCTYPE html> | |
<html> | |
<head> | |
<meta charset=utf-8 /> | |
<title>Loading markers from CSV</title> | |
<meta name='viewport' content='width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no' /> | |
<style> | |
.wrap { | |
max-width:500px; | |
margin:0 auto; | |
} | |
#geojson { | |
width:100%; | |
} | |
</style> | |
</head> | |
<body> | |
<div class='wrap'> | |
<br /> | |
GeoJSON | |
<textarea class="topcoat-textarea" id='geojson'></textarea> | |
<br /> | |
Low Zoom | |
<br /> | |
<input id='low-zoom' /> | |
<br /> | |
High Zoom | |
<br /> | |
<input id='high-zoom' /> | |
<br /> | |
<button id='compute'>Compute</button> | |
<br /> | |
Tiles required | |
<h1 id='count'>0</h1> | |
</div> | |
<script src='bundle.js'></script> | |
</body> | |
</html> |
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