graham-scan-convex-hull
Version:
graham scan convex hull algorithm
122 lines (95 loc) • 12.6 kB
JavaScript
(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);var f=new Error("Cannot find module '"+o+"'");throw f.code="MODULE_NOT_FOUND",f}var l=n[o]={exports:{}};t[o][0].call(l.exports,function(e){var n=t[o][1][e];return s(n?n:e)},l,l.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 convexHull = require('../../src/convex-hull.js');
var osm = L.tileLayer('http://{s}.basemaps.cartocdn.com/light_nolabels/{z}/{x}/{y}.png', {
maxZoom: 22,
attribution: 'Map data © <a href="http://openstreetmap.org">OpenStreetMap</a> contributors, <a href="http://creativecommons.org/licenses/by-sa/2.0/">CC-BY-SA</a>'
}),
point = L.latLng([55.753210, 37.621766]),
lmap = new L.Map('map', { layers: [osm], center: point, zoom: 12, maxZoom: 22 }),
generateButton = document.getElementsByClassName('generate')[0],
pointsNumberButton = document.getElementsByClassName('points-number')[0],
markers,
polygon;
function drawHull() {
if (markers) {
lmap.removeLayer(markers);
}
if (polygon) {
lmap.removeLayer(polygon);
}
var bounds = lmap.getBounds(),
n = bounds._northEast.lat,
e = bounds._northEast.lng,
s = bounds._southWest.lat,
w = bounds._southWest.lng,
height = n - s,
width = e - w,
qHeight = height / 4,
qWidth = width / 4,
pointsNumber = pointsNumberButton.value,
points,
coords,
res,
lls;
points = turf.random('points', pointsNumber, {
bbox: [w + qWidth, s + qHeight, e - qWidth, n - qHeight]
});
coords = points.features.map(function (feature) {
return feature.geometry.coordinates;
});
res = convexHull(coords);
lls = res.map(function (coord) {
return L.latLng([coord[1], coord[0]]);
});
markers = L.geoJson(points, {
pointToLayer: function (feature, latlng) {
return L.circleMarker(latlng, { radius: 3, fillColor: "#ffff00" });
}
}).addTo(lmap);
polygon = L.polygon(lls, { color: "#ffb90f" }).addTo(lmap);
}
generateButton.onclick = drawHull;
drawHull();
},{"../../src/convex-hull.js":2}],2:[function(require,module,exports){
function convexHull(data) {
var upperArr = [],
lowerArr = [],
clone;
clone = data.slice();
clone.sort(function (a, b) {
return a[0] - b[0];
});
// calculate the upper hull
for (var i = 0; i < clone.length; i++) {
var point = clone[i];
upperArr.push(point);
removePoints(upperArr);
}
// calculate the lower hull
for (var j = clone.length - 1; j >= 0; j--) {
var point = clone[j];
lowerArr.push(point);
removePoints(lowerArr);
}
lowerArr.splice(0, 1);
lowerArr.splice(lowerArr.length - 1, 1);
// concat hulls
return upperArr.concat(lowerArr);
}
function removePoints(arr) {
while (arr.length >= 3 && !isTurnRight(arr[arr.length - 3], arr[arr.length - 2], arr[arr.length - 1])) {
arr.splice(arr.length - 2, 1);
}
}
function isTurnRight(point1, point2, point3) {
var x1 = point1[0],
x2 = point2[0],
x3 = point3[0],
y1 = point1[1],
y2 = point2[1],
y3 = point3[1];
return (x2 - x1) * (y3 - y1) - (y2 - y1) * (x3 - x1) > 0;
}
module.exports = convexHull;
},{}]},{},[1])
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<a href=\"http://openstreetmap.org\">OpenStreetMap</a> contributors, <a href=\"http://creativecommons.org/licenses/by-sa/2.0/\">CC-BY-SA</a>'\n    }),\n    point = L.latLng([55.753210, 37.621766]),\n    lmap = new L.Map('map', {layers: [osm], center: point, zoom: 12, maxZoom: 22}),\n    generateButton = document.getElementsByClassName('generate')[0],\n    pointsNumberButton = document.getElementsByClassName('points-number')[0],\n    markers,\n    polygon;\n\nfunction drawHull() {\n    if (markers) {\n        lmap.removeLayer(markers);\n    }\n\n    if (polygon) {\n        lmap.removeLayer(polygon);\n    }\n\n    var bounds = lmap.getBounds(),\n        n = bounds._northEast.lat,\n        e = bounds._northEast.lng,\n        s = bounds._southWest.lat,\n        w = bounds._southWest.lng,\n        height = n - s,\n        width = e - w,\n        qHeight = height / 4,\n        qWidth = width / 4,\n        pointsNumber = pointsNumberButton.value,\n        points,\n        coords,\n        res,\n        lls;\n\n    points = turf.random('points', pointsNumber, {\n        bbox: [w + qWidth, s + qHeight, e - qWidth, n - qHeight]\n    });\n\n    coords = points.features.map(function (feature) {\n        return feature.geometry.coordinates;\n    });\n\n    res = convexHull(coords);\n\n    lls = res.map(function(coord) {\n        return L.latLng([coord[1],coord[0]]);\n    });\n\n    markers = L.geoJson(points, {\n        pointToLayer: function (feature, latlng) {\n            return L.circleMarker(latlng, {radius: 3, fillColor: \"#ffff00\"});\n        }\n    }).addTo(lmap);\n\n    polygon = L.polygon(lls, {color: \"#ffb90f\"}).addTo(lmap);\n}\n\ngenerateButton.onclick = drawHull;\n\ndrawHull();\n","function convexHull(data) {\n    var upperArr = [],\n        lowerArr = [],\n        clone;\n\n    clone = data.slice();\n\n    clone.sort(function (a, b) {\n        return a[0] - b[0];\n    });\n\n    // calculate the upper hull\n    for (var i = 0; i < clone.length; i++) {\n        var point = clone[i];\n\n        upperArr.push(point);\n        removePoints(upperArr);\n    }\n\n    // calculate the lower hull\n    for (var j = clone.length - 1; j >= 0; j--) {\n        var point = clone[j];\n\n        lowerArr.push(point);\n        removePoints(lowerArr);\n    }\n\n    lowerArr.splice(0, 1);\n    lowerArr.splice(lowerArr.length - 1, 1);\n\n    // concat hulls\n    return upperArr.concat(lowerArr);\n}\n\nfunction removePoints(arr) {\n    while (arr.length >= 3 && !isTurnRight(arr[arr.length-3], arr[arr.length-2], arr[arr.length-1])) {\n        arr.splice(arr.length-2, 1);\n    }\n}\n\nfunction isTurnRight(point1, point2, point3) {\n    var x1 = point1[0],\n        x2 = point2[0],\n        x3 = point3[0],\n        y1 = point1[1],\n        y2 = point2[1],\n        y3 = point3[1];\n\n    return ((x2 - x1) * (y3 - y1) - (y2 - y1) * (x3 - x1)) > 0;\n}\n\nmodule.exports = convexHull;\n"]}