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Temporarily add transpiled BRouter CheapRuler

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for better comparison during development
This commit is contained in:
Norbert Renner 2021-10-08 19:40:41 +02:00
parent af1a11872a
commit bd2e89ef06
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js/util/CheapRuler.js Normal file
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/* Generated from Java with JSweet 3.1.0 - http://www.jsweet.org */
//var btools;
btools = {};
(function (btools) {
var util;
(function (util) {
class CheapRuler {
static __static_initialize() {
if (!CheapRuler.__static_initialized) {
CheapRuler.__static_initialized = true;
CheapRuler.__static_initializer_0();
}
}
static DEG_TO_RAD_$LI$() {
CheapRuler.__static_initialize();
if (CheapRuler.DEG_TO_RAD == null) {
CheapRuler.DEG_TO_RAD = Math.PI / 180.0;
}
return CheapRuler.DEG_TO_RAD;
}
static SCALE_CACHE_$LI$() {
CheapRuler.__static_initialize();
if (CheapRuler.SCALE_CACHE == null) {
CheapRuler.SCALE_CACHE = ((s) => {
let a = [];
while (s-- > 0) a.push(null);
return a;
})(CheapRuler.SCALE_CACHE_LENGTH);
}
return CheapRuler.SCALE_CACHE;
}
static __static_initializer_0() {
for (let i = 0; i < CheapRuler.SCALE_CACHE_LENGTH; i++) {
{
CheapRuler.SCALE_CACHE_$LI$()[i] = CheapRuler.calcKxKyFromILat(
i * CheapRuler.SCALE_CACHE_INCREMENT + ((CheapRuler.SCALE_CACHE_INCREMENT / 2) | 0)
);
}
}
}
/*private*/ static calcKxKyFromILat(ilat) {
const lat = CheapRuler.DEG_TO_RAD_$LI$() * (ilat * CheapRuler.ILATLNG_TO_LATLNG - 90);
const cos = Math.cos(lat);
const cos2 = 2 * cos * cos - 1;
const cos3 = 2 * cos * cos2 - cos;
const cos4 = 2 * cos * cos3 - cos2;
const cos5 = 2 * cos * cos4 - cos3;
const kxky = [0, 0];
kxky[0] =
(111.41513 * cos - 0.09455 * cos3 + 1.2e-4 * cos5) *
CheapRuler.ILATLNG_TO_LATLNG *
CheapRuler.KILOMETERS_TO_METERS;
kxky[1] =
(111.13209 - 0.56605 * cos2 + 0.0012 * cos4) *
CheapRuler.ILATLNG_TO_LATLNG *
CheapRuler.KILOMETERS_TO_METERS;
return kxky;
}
/**
* Calculate the degree-&gt;meter scale for given latitude
*
* @return {double[]} [lon-&gt;meter,lat-&gt;meter]
* @param {number} ilat
*/
static getLonLatToMeterScales(ilat) {
return CheapRuler.SCALE_CACHE_$LI$()[(ilat / CheapRuler.SCALE_CACHE_INCREMENT) | 0];
}
/**
* Compute the distance (in meters) between two points represented by their
* (integer) latitude and longitude.
*
* @param {number} ilon1 Integer longitude for the start point. this is (longitude in degrees + 180) * 1e6.
* @param {number} ilat1 Integer latitude for the start point, this is (latitude + 90) * 1e6.
* @param {number} ilon2 Integer longitude for the end point, this is (longitude + 180) * 1e6.
* @param {number} ilat2 Integer latitude for the end point, this is (latitude + 90) * 1e6.
* @return {number} The distance between the two points, in meters.
*
* Note:
* Integer longitude is ((longitude in degrees) + 180) * 1e6.
* Integer latitude is ((latitude in degrees) + 90) * 1e6.
*/
static distance(ilon1, ilat1, ilon2, ilat2) {
const kxky = CheapRuler.getLonLatToMeterScales((ilat1 + ilat2) >> 1);
const dlon = (ilon1 - ilon2) * kxky[0];
const dlat = (ilat1 - ilat2) * kxky[1];
return Math.sqrt(dlat * dlat + dlon * dlon);
}
}
CheapRuler.__static_initialized = false;
/**
* Cheap-Ruler Java implementation
* See
* https://blog.mapbox.com/fast-geodesic-approximations-with-cheap-ruler-106f229ad016
* for more details.
*
* Original code is at https://github.com/mapbox/cheap-ruler under ISC license.
*
* This is implemented as a Singleton to have a unique cache for the cosine
* values across all the code.
*/
CheapRuler.ILATLNG_TO_LATLNG = 1.0e-6;
CheapRuler.KILOMETERS_TO_METERS = 1000;
CheapRuler.SCALE_CACHE_LENGTH = 1800;
CheapRuler.SCALE_CACHE_INCREMENT = 100000;
util.CheapRuler = CheapRuler;
CheapRuler['__class'] = 'btools.util.CheapRuler';
})((util = btools.util || (btools.util = {})));
})(btools || (btools = {}));
btools.util.CheapRuler.__static_initialize();