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Last active June 14, 2018 14:01
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Leaflet coordinates helper
const L = require('./leaflet-0.5.0-coord-part')
const simpleCrs = L.Util.extend({}, L.CRS, {
code : 'simple',
projection : L.Projection.LonLat,
transformation : new L.Transformation(1,0,-1,0)
})
console.log(
L.CRS.EPSG3857.pointToLatLng(
simpleCrs.latLngToPoint({
"lat": -0.6068115234375,
"lng": 0.82440185546875
}, 1), 1))
/*
Leaflet, a JavaScript library for mobile-friendly interactive maps. http://leafletjs.com
(c) 2010-2013, Vladimir Agafonkin, CloudMade
*/
/*
* Leaflet coordinates helper
* Mofified for NodeJS
*/
var L, originalL;
if (typeof exports !== undefined + '') {
L = exports;
} else {
originalL = window.L;
L = {};
L.noConflict = function () {
window.L = originalL;
return this;
};
window.L = L;
}
L.version = '0.5.1';
/*
* L.Util contains various utility functions used throughout Leaflet code.
*/
L.Util = {
extend: function (dest) { // (Object[, Object, ...]) ->
var sources = Array.prototype.slice.call(arguments, 1),
i, j, len, src;
for (j = 0, len = sources.length; j < len; j++) {
src = sources[j] || {};
for (i in src) {
if (src.hasOwnProperty(i)) {
dest[i] = src[i];
}
}
}
return dest;
},
bind: function (fn, obj) { // (Function, Object) -> Function
var args = arguments.length > 2 ? Array.prototype.slice.call(arguments, 2) : null;
return function () {
return fn.apply(obj, args || arguments);
};
},
stamp: (function () {
var lastId = 0, key = '_leaflet_id';
return function (/*Object*/ obj) {
obj[key] = obj[key] || ++lastId;
return obj[key];
};
}()),
limitExecByInterval: function (fn, time, context) {
var lock, execOnUnlock;
return function wrapperFn() {
var args = arguments;
if (lock) {
execOnUnlock = true;
return;
}
lock = true;
setTimeout(function () {
lock = false;
if (execOnUnlock) {
wrapperFn.apply(context, args);
execOnUnlock = false;
}
}, time);
fn.apply(context, args);
};
},
falseFn: function () {
return false;
},
formatNum: function (num, digits) {
var pow = Math.pow(10, digits || 5);
return Math.round(num * pow) / pow;
},
splitWords: function (str) {
return str.replace(/^\s+|\s+$/g, '').split(/\s+/);
},
setOptions: function (obj, options) {
obj.options = L.extend({}, obj.options, options);
return obj.options;
},
getParamString: function (obj, existingUrl) {
var params = [];
for (var i in obj) {
if (obj.hasOwnProperty(i)) {
params.push(i + '=' + obj[i]);
}
}
return ((!existingUrl || existingUrl.indexOf('?') === -1) ? '?' : '&') + params.join('&');
},
template: function (str, data) {
return str.replace(/\{ *([\w_]+) *\}/g, function (str, key) {
var value = data[key];
if (!data.hasOwnProperty(key)) {
throw new Error('No value provided for variable ' + str);
}
return value;
});
},
isArray: function (obj) {
return (Object.prototype.toString.call(obj) === '[object Array]');
},
emptyImageUrl: 'data:image/gif;base64,R0lGODlhAQABAAD/ACwAAAAAAQABAAACADs='
};
// shortcuts for most used utility functions
L.extend = L.Util.extend;
L.bind = L.Util.bind;
L.stamp = L.Util.stamp;
L.setOptions = L.Util.setOptions;
/*
* L.Point represents a point with x and y coordinates.
*/
L.Point = function (/*Number*/ x, /*Number*/ y, /*Boolean*/ round) {
this.x = (round ? Math.round(x) : x);
this.y = (round ? Math.round(y) : y);
};
L.Point.prototype = {
clone: function () {
return new L.Point(this.x, this.y);
},
// non-destructive, returns a new point
add: function (point) {
return this.clone()._add(L.point(point));
},
// destructive, used directly for performance in situations where it's safe to modify existing point
_add: function (point) {
this.x += point.x;
this.y += point.y;
return this;
},
subtract: function (point) {
return this.clone()._subtract(L.point(point));
},
_subtract: function (point) {
this.x -= point.x;
this.y -= point.y;
return this;
},
divideBy: function (num) {
return this.clone()._divideBy(num);
},
_divideBy: function (num) {
this.x /= num;
this.y /= num;
return this;
},
multiplyBy: function (num) {
return this.clone()._multiplyBy(num);
},
_multiplyBy: function (num) {
this.x *= num;
this.y *= num;
return this;
},
round: function () {
return this.clone()._round();
},
_round: function () {
this.x = Math.round(this.x);
this.y = Math.round(this.y);
return this;
},
floor: function () {
return this.clone()._floor();
},
_floor: function () {
this.x = Math.floor(this.x);
this.y = Math.floor(this.y);
return this;
},
distanceTo: function (point) {
point = L.point(point);
var x = point.x - this.x,
y = point.y - this.y;
return Math.sqrt(x * x + y * y);
},
equals: function (point) {
return point.x === this.x &&
point.y === this.y;
},
toString: function () {
return 'Point(' +
L.Util.formatNum(this.x) + ', ' +
L.Util.formatNum(this.y) + ')';
}
};
L.point = function (x, y, round) {
if (x instanceof L.Point) {
return x;
}
if (L.Util.isArray(x)) {
return new L.Point(x[0], x[1]);
}
if (isNaN(x)) {
return x;
}
return new L.Point(x, y, round);
};
/*
* L.Bounds represents a rectangular area on the screen in pixel coordinates.
*/
L.Bounds = function (a, b) { //(Point, Point) or Point[]
if (!a) { return; }
var points = b ? [a, b] : a;
for (var i = 0, len = points.length; i < len; i++) {
this.extend(points[i]);
}
};
L.Bounds.prototype = {
// extend the bounds to contain the given point
extend: function (point) { // (Point)
point = L.point(point);
if (!this.min && !this.max) {
this.min = point.clone();
this.max = point.clone();
} else {
this.min.x = Math.min(point.x, this.min.x);
this.max.x = Math.max(point.x, this.max.x);
this.min.y = Math.min(point.y, this.min.y);
this.max.y = Math.max(point.y, this.max.y);
}
return this;
},
getCenter: function (round) { // (Boolean) -> Point
return new L.Point(
(this.min.x + this.max.x) / 2,
(this.min.y + this.max.y) / 2, round);
},
getBottomLeft: function () { // -> Point
return new L.Point(this.min.x, this.max.y);
},
getTopRight: function () { // -> Point
return new L.Point(this.max.x, this.min.y);
},
getSize: function () {
return this.max.subtract(this.min);
},
contains: function (obj) { // (Bounds) or (Point) -> Boolean
var min, max;
if (typeof obj[0] === 'number' || obj instanceof L.Point) {
obj = L.point(obj);
} else {
obj = L.bounds(obj);
}
if (obj instanceof L.Bounds) {
min = obj.min;
max = obj.max;
} else {
min = max = obj;
}
return (min.x >= this.min.x) &&
(max.x <= this.max.x) &&
(min.y >= this.min.y) &&
(max.y <= this.max.y);
},
intersects: function (bounds) { // (Bounds) -> Boolean
bounds = L.bounds(bounds);
var min = this.min,
max = this.max,
min2 = bounds.min,
max2 = bounds.max,
xIntersects = (max2.x >= min.x) && (min2.x <= max.x),
yIntersects = (max2.y >= min.y) && (min2.y <= max.y);
return xIntersects && yIntersects;
},
isValid: function () {
return !!(this.min && this.max);
}
};
L.bounds = function (a, b) { // (Bounds) or (Point, Point) or (Point[])
if (!a || a instanceof L.Bounds) {
return a;
}
return new L.Bounds(a, b);
};
/*
* L.Transformation is an utility class to perform simple point transformations through a 2d-matrix.
*/
L.Transformation = function (a, b, c, d) {
this._a = a;
this._b = b;
this._c = c;
this._d = d;
};
L.Transformation.prototype = {
transform: function (point, scale) { // (Point, Number) -> Point
return this._transform(point.clone(), scale);
},
// destructive transform (faster)
_transform: function (point, scale) {
scale = scale || 1;
point.x = scale * (this._a * point.x + this._b);
point.y = scale * (this._c * point.y + this._d);
return point;
},
untransform: function (point, scale) {
scale = scale || 1;
return new L.Point(
(point.x / scale - this._b) / this._a,
(point.y / scale - this._d) / this._c);
}
};
/*
* L.LatLng represents a geographical point with latitude and longitude coordinates.
*/
L.LatLng = function (rawLat, rawLng) { // (Number, Number)
var lat = parseFloat(rawLat),
lng = parseFloat(rawLng);
if (isNaN(lat) || isNaN(lng)) {
throw new Error('Invalid LatLng object: (' + rawLat + ', ' + rawLng + ')');
}
this.lat = lat;
this.lng = lng;
};
L.extend(L.LatLng, {
DEG_TO_RAD: Math.PI / 180,
RAD_TO_DEG: 180 / Math.PI,
MAX_MARGIN: 1.0E-9 // max margin of error for the "equals" check
});
L.LatLng.prototype = {
equals: function (obj) { // (LatLng) -> Boolean
if (!obj) { return false; }
obj = L.latLng(obj);
var margin = Math.max(
Math.abs(this.lat - obj.lat),
Math.abs(this.lng - obj.lng));
return margin <= L.LatLng.MAX_MARGIN;
},
toString: function (precision) { // (Number) -> String
return 'LatLng(' +
L.Util.formatNum(this.lat, precision) + ', ' +
L.Util.formatNum(this.lng, precision) + ')';
},
// Haversine distance formula, see http://en.wikipedia.org/wiki/Haversine_formula
// TODO move to projection code, LatLng shouldn't know about Earth
distanceTo: function (other) { // (LatLng) -> Number
other = L.latLng(other);
var R = 6378137, // earth radius in meters
d2r = L.LatLng.DEG_TO_RAD,
dLat = (other.lat - this.lat) * d2r,
dLon = (other.lng - this.lng) * d2r,
lat1 = this.lat * d2r,
lat2 = other.lat * d2r,
sin1 = Math.sin(dLat / 2),
sin2 = Math.sin(dLon / 2);
var a = sin1 * sin1 + sin2 * sin2 * Math.cos(lat1) * Math.cos(lat2);
return R * 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));
},
wrap: function (a, b) { // (Number, Number) -> LatLng
var lng = this.lng;
a = a || -180;
b = b || 180;
lng = (lng + b) % (b - a) + (lng < a || lng === b ? b : a);
return new L.LatLng(this.lat, lng);
}
};
L.latLng = function (a, b) { // (LatLng) or ([Number, Number]) or (Number, Number)
if (a instanceof L.LatLng) {
return a;
}
if (L.Util.isArray(a)) {
return new L.LatLng(a[0], a[1]);
}
if (isNaN(a)) {
return a;
}
return new L.LatLng(a, b);
};
/*
* L.LatLngBounds represents a rectangular area on the map in geographical coordinates.
*/
L.LatLngBounds = function (southWest, northEast) { // (LatLng, LatLng) or (LatLng[])
if (!southWest) { return; }
var latlngs = northEast ? [southWest, northEast] : southWest;
for (var i = 0, len = latlngs.length; i < len; i++) {
this.extend(latlngs[i]);
}
};
L.LatLngBounds.prototype = {
// extend the bounds to contain the given point or bounds
extend: function (obj) { // (LatLng) or (LatLngBounds)
if (typeof obj[0] === 'number' || typeof obj[0] === 'string' || obj instanceof L.LatLng) {
obj = L.latLng(obj);
} else {
obj = L.latLngBounds(obj);
}
if (obj instanceof L.LatLng) {
if (!this._southWest && !this._northEast) {
this._southWest = new L.LatLng(obj.lat, obj.lng);
this._northEast = new L.LatLng(obj.lat, obj.lng);
} else {
this._southWest.lat = Math.min(obj.lat, this._southWest.lat);
this._southWest.lng = Math.min(obj.lng, this._southWest.lng);
this._northEast.lat = Math.max(obj.lat, this._northEast.lat);
this._northEast.lng = Math.max(obj.lng, this._northEast.lng);
}
} else if (obj instanceof L.LatLngBounds) {
this.extend(obj._southWest);
this.extend(obj._northEast);
}
return this;
},
// extend the bounds by a percentage
pad: function (bufferRatio) { // (Number) -> LatLngBounds
var sw = this._southWest,
ne = this._northEast,
heightBuffer = Math.abs(sw.lat - ne.lat) * bufferRatio,
widthBuffer = Math.abs(sw.lng - ne.lng) * bufferRatio;
return new L.LatLngBounds(
new L.LatLng(sw.lat - heightBuffer, sw.lng - widthBuffer),
new L.LatLng(ne.lat + heightBuffer, ne.lng + widthBuffer));
},
getCenter: function () { // -> LatLng
return new L.LatLng(
(this._southWest.lat + this._northEast.lat) / 2,
(this._southWest.lng + this._northEast.lng) / 2);
},
getSouthWest: function () {
return this._southWest;
},
getNorthEast: function () {
return this._northEast;
},
getNorthWest: function () {
return new L.LatLng(this._northEast.lat, this._southWest.lng);
},
getSouthEast: function () {
return new L.LatLng(this._southWest.lat, this._northEast.lng);
},
contains: function (obj) { // (LatLngBounds) or (LatLng) -> Boolean
if (typeof obj[0] === 'number' || obj instanceof L.LatLng) {
obj = L.latLng(obj);
} else {
obj = L.latLngBounds(obj);
}
var sw = this._southWest,
ne = this._northEast,
sw2, ne2;
if (obj instanceof L.LatLngBounds) {
sw2 = obj.getSouthWest();
ne2 = obj.getNorthEast();
} else {
sw2 = ne2 = obj;
}
return (sw2.lat >= sw.lat) && (ne2.lat <= ne.lat) &&
(sw2.lng >= sw.lng) && (ne2.lng <= ne.lng);
},
intersects: function (bounds) { // (LatLngBounds)
bounds = L.latLngBounds(bounds);
var sw = this._southWest,
ne = this._northEast,
sw2 = bounds.getSouthWest(),
ne2 = bounds.getNorthEast(),
latIntersects = (ne2.lat >= sw.lat) && (sw2.lat <= ne.lat),
lngIntersects = (ne2.lng >= sw.lng) && (sw2.lng <= ne.lng);
return latIntersects && lngIntersects;
},
toBBoxString: function () {
var sw = this._southWest,
ne = this._northEast;
return [sw.lng, sw.lat, ne.lng, ne.lat].join(',');
},
equals: function (bounds) { // (LatLngBounds)
if (!bounds) { return false; }
bounds = L.latLngBounds(bounds);
return this._southWest.equals(bounds.getSouthWest()) &&
this._northEast.equals(bounds.getNorthEast());
},
isValid: function () {
return !!(this._southWest && this._northEast);
}
};
//TODO International date line?
L.latLngBounds = function (a, b) { // (LatLngBounds) or (LatLng, LatLng)
if (!a || a instanceof L.LatLngBounds) {
return a;
}
return new L.LatLngBounds(a, b);
};
/*
* L.Projection contains various geographical projections used by CRS classes.
*/
L.Projection = {};
/*
* Spherical Mercator is the most popular map projection, used by EPSG:3857 CRS used by default.
*/
L.Projection.SphericalMercator = {
MAX_LATITUDE: 85.0511287798,
project: function (latlng) { // (LatLng) -> Point
var d = L.LatLng.DEG_TO_RAD,
max = this.MAX_LATITUDE,
lat = Math.max(Math.min(max, latlng.lat), -max),
x = latlng.lng * d,
y = lat * d;
y = Math.log(Math.tan((Math.PI / 4) + (y / 2)));
return new L.Point(x, y);
},
unproject: function (point) { // (Point, Boolean) -> LatLng
var d = L.LatLng.RAD_TO_DEG,
lng = point.x * d,
lat = (2 * Math.atan(Math.exp(point.y)) - (Math.PI / 2)) * d;
return new L.LatLng(lat, lng);
}
};
/*
* Simple equirectangular (Plate Carree) projection, used by CRS like EPSG:4326 and Simple.
*/
L.Projection.LonLat = {
project: function (latlng) {
return new L.Point(latlng.lng, latlng.lat);
},
unproject: function (point) {
return new L.LatLng(point.y, point.x);
}
};
/*
* L.CRS is a base object for all defined CRS (Coordinate Reference Systems) in Leaflet.
*/
L.CRS = {
latLngToPoint: function (latlng, zoom) { // (LatLng, Number) -> Point
var projectedPoint = this.projection.project(latlng),
scale = this.scale(zoom);
return this.transformation._transform(projectedPoint, scale);
},
pointToLatLng: function (point, zoom) { // (Point, Number[, Boolean]) -> LatLng
var scale = this.scale(zoom),
untransformedPoint = this.transformation.untransform(point, scale);
return this.projection.unproject(untransformedPoint);
},
project: function (latlng) {
return this.projection.project(latlng);
},
scale: function (zoom) {
return 256 * Math.pow(2, zoom);
}
};
/*
* A simple CRS that can be used for flat non-Earth maps like panoramas or game maps.
*/
L.CRS.Simple = L.extend({}, L.CRS, {
projection: L.Projection.LonLat,
transformation: new L.Transformation(1, 0, -1, 0),
scale: function (zoom) {
return Math.pow(2, zoom);
}
});
/*
* L.CRS.EPSG3857 (Spherical Mercator) is the most common CRS for web mapping
* and is used by Leaflet by default.
*/
L.CRS.EPSG3857 = L.extend({}, L.CRS, {
code: 'EPSG:3857',
projection: L.Projection.SphericalMercator,
transformation: new L.Transformation(0.5 / Math.PI, 0.5, -0.5 / Math.PI, 0.5),
project: function (latlng) { // (LatLng) -> Point
var projectedPoint = this.projection.project(latlng),
earthRadius = 6378137;
return projectedPoint.multiplyBy(earthRadius);
}
});
L.CRS.EPSG900913 = L.extend({}, L.CRS.EPSG3857, {
code: 'EPSG:900913'
});
/*
* L.CRS.EPSG4326 is a CRS popular among advanced GIS specialists.
*/
L.CRS.EPSG4326 = L.extend({}, L.CRS, {
code: 'EPSG:4326',
projection: L.Projection.LonLat,
transformation: new L.Transformation(1 / 360, 0.5, -1 / 360, 0.5)
});
/*
* Mercator projection that takes into account that the Earth is not a perfect sphere.
* Less popular than spherical mercator; used by projections like EPSG:3395.
*/
L.Projection.Mercator = {
MAX_LATITUDE: 85.0840591556,
R_MINOR: 6356752.3142,
R_MAJOR: 6378137,
project: function (latlng) { // (LatLng) -> Point
var d = L.LatLng.DEG_TO_RAD,
max = this.MAX_LATITUDE,
lat = Math.max(Math.min(max, latlng.lat), -max),
r = this.R_MAJOR,
r2 = this.R_MINOR,
x = latlng.lng * d * r,
y = lat * d,
tmp = r2 / r,
eccent = Math.sqrt(1.0 - tmp * tmp),
con = eccent * Math.sin(y);
con = Math.pow((1 - con) / (1 + con), eccent * 0.5);
var ts = Math.tan(0.5 * ((Math.PI * 0.5) - y)) / con;
y = -r2 * Math.log(ts);
return new L.Point(x, y);
},
unproject: function (point) { // (Point, Boolean) -> LatLng
var d = L.LatLng.RAD_TO_DEG,
r = this.R_MAJOR,
r2 = this.R_MINOR,
lng = point.x * d / r,
tmp = r2 / r,
eccent = Math.sqrt(1 - (tmp * tmp)),
ts = Math.exp(- point.y / r2),
phi = (Math.PI / 2) - 2 * Math.atan(ts),
numIter = 15,
tol = 1e-7,
i = numIter,
dphi = 0.1,
con;
while ((Math.abs(dphi) > tol) && (--i > 0)) {
con = eccent * Math.sin(phi);
dphi = (Math.PI / 2) - 2 * Math.atan(ts *
Math.pow((1.0 - con) / (1.0 + con), 0.5 * eccent)) - phi;
phi += dphi;
}
return new L.LatLng(phi * d, lng);
}
};
L.CRS.EPSG3395 = L.extend({}, L.CRS, {
code: 'EPSG:3395',
projection: L.Projection.Mercator,
transformation: (function () {
var m = L.Projection.Mercator,
r = m.R_MAJOR,
r2 = m.R_MINOR;
return new L.Transformation(0.5 / (Math.PI * r), 0.5, -0.5 / (Math.PI * r2), 0.5);
}())
});
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