(function(f){if(typeof exports==="object"&&typeof module!=="undefined"){module.exports=f()}else if(typeof define==="function"&&define.amd){define([],f)}else{var g;if(typeof window!=="undefined"){g=window}else if(typeof global!=="undefined"){g=global}else if(typeof self!=="undefined"){g=self}else{g=this}g.polylabel = f()}})(function(){var define,module,exports;return (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 maxX) maxX = p[0]; if (!i || p[1] > maxY) maxY = p[1]; } var width = maxX - minX; var height = maxY - minY; var cellSize = Math.min(width, height); var h = cellSize / 2; // a priority queue of cells in order of their "potential" (max distance to polygon) var cellQueue = new Queue(null, compareMax); // cover polygon with initial cells for (var x = minX; x < maxX; x += cellSize) { for (var y = minY; y < maxY; y += cellSize) { cellQueue.push(new Cell(x + h, y + h, h, polygon)); } } // take centroid as the first best guess var bestCell = getCentroidCell(polygon); var numProbes = cellQueue.length; while (cellQueue.length) { // pick the most promising cell from the queue var cell = cellQueue.pop(); // update the best cell if we found a better one if (cell.d > bestCell.d) { bestCell = cell; if (debug) console.log('found best %d after %d probes', Math.round(1e4 * cell.d) / 1e4, numProbes); } // do not drill down further if there's no chance of a better solution if (cell.max - bestCell.d <= precision) continue; // split the cell into four cells h = cell.h / 2; cellQueue.push(new Cell(cell.x - h, cell.y - h, h, polygon)); cellQueue.push(new Cell(cell.x + h, cell.y - h, h, polygon)); cellQueue.push(new Cell(cell.x - h, cell.y + h, h, polygon)); cellQueue.push(new Cell(cell.x + h, cell.y + h, h, polygon)); numProbes += 4; } if (debug) { console.log('num probes: ' + numProbes); console.log('best distance: ' + bestCell.d); } return [bestCell.x, bestCell.y]; } function compareMax(a, b) { return b.max - a.max; } function Cell(x, y, h, polygon) { this.x = x; // cell center x this.y = y; // cell center y this.h = h; // half the cell size this.d = pointToPolygonDist(x, y, polygon); // distance from cell center to polygon this.max = this.d + this.h * Math.SQRT2; // max distance to polygon within a cell } // signed distance from point to polygon outline (negative if point is outside) function pointToPolygonDist(x, y, polygon) { var inside = false; var minDistSq = Infinity; for (var k = 0; k < polygon.length; k++) { var ring = polygon[k]; for (var i = 0, len = ring.length, j = len - 1; i < len; j = i++) { var a = ring[i]; var b = ring[j]; if ((a[1] > y !== b[1] > y) && (x < (b[0] - a[0]) * (y - a[1]) / (b[1] - a[1]) + a[0])) inside = !inside; minDistSq = Math.min(minDistSq, getSegDistSq(x, y, a, b)); } } return (inside ? 1 : -1) * Math.sqrt(minDistSq); } // get polygon centroid function getCentroidCell(polygon) { var area = 0; var x = 0; var y = 0; var points = polygon[0]; for (var i = 0, len = points.length, j = len - 1; i < len; j = i++) { var a = points[i]; var b = points[j]; var f = a[0] * b[1] - b[0] * a[1]; x += (a[0] + b[0]) * f; y += (a[1] + b[1]) * f; area += f * 3; } return new Cell(x / area, y / area, 0, polygon); } // get squared distance from a point to a segment function getSegDistSq(px, py, a, b) { var x = a[0]; var y = a[1]; var dx = b[0] - x; var dy = b[1] - y; if (dx !== 0 || dy !== 0) { var t = ((px - x) * dx + (py - y) * dy) / (dx * dx + dy * dy); if (t > 1) { x = b[0]; y = b[1]; } else if (t > 0) { x += dx * t; y += dy * t; } } dx = px - x; dy = py - y; return dx * dx + dy * dy; } },{"tinyqueue":2}],2:[function(require,module,exports){ 'use strict'; module.exports = TinyQueue; function TinyQueue(data, compare) { if (!(this instanceof TinyQueue)) return new TinyQueue(data, compare); this.data = data || []; this.length = this.data.length; this.compare = compare || defaultCompare; if (data) for (var i = Math.floor(this.length / 2); i >= 0; i--) this._down(i); } function defaultCompare(a, b) { return a < b ? -1 : a > b ? 1 : 0; } TinyQueue.prototype = { push: function (item) { this.data.push(item); this.length++; this._up(this.length - 1); }, pop: function () { var top = this.data[0]; this.data[0] = this.data[this.length - 1]; this.length--; this.data.pop(); this._down(0); return top; }, peek: function () { return this.data[0]; }, _up: function (pos) { var data = this.data, compare = this.compare; while (pos > 0) { var parent = Math.floor((pos - 1) / 2); if (compare(data[pos], data[parent]) < 0) { swap(data, parent, pos); pos = parent; } else break; } }, _down: function (pos) { var data = this.data, compare = this.compare, len = this.length; while (true) { var left = 2 * pos + 1, right = left + 1, min = pos; if (left < len && compare(data[left], data[min]) < 0) min = left; if (right < len && compare(data[right], data[min]) < 0) min = right; if (min === pos) return; swap(data, min, pos); pos = min; } } }; function swap(data, i, j) { var tmp = data[i]; data[i] = data[j]; data[j] = tmp; } },{}]},{},[1])(1) });