function ConvexHullGrahamScan(){this.anchorPoint=void 0,this.reverse=!1,this.points=[]}ConvexHullGrahamScan.prototype={constructor:ConvexHullGrahamScan,Point:function(n,t){this.x=n,this.y=t},_findPolarAngle:function(n,t){var i,o,h=57.295779513082;if(!n||!t)return 0;if(i=t.x-n.x,o=t.y-n.y,0==i&&0==o)return 0;var r=Math.atan2(o,i)*h;return this.reverse?0>=r&&(r+=360):r>=0&&(r+=360),r},addPoint:function(n,t){return void 0===this.anchorPoint?void(this.anchorPoint=new this.Point(n,t)):this.anchorPoint.y>t&&this.anchorPoint.x>n||this.anchorPoint.y===t&&this.anchorPoint.x>n||this.anchorPoint.y>t&&this.anchorPoint.x===n?(this.points.push(new this.Point(this.anchorPoint.x,this.anchorPoint.y)),void(this.anchorPoint=new this.Point(n,t))):void this.points.push(new this.Point(n,t))},_sortPoints:function(){var n=this;return this.points.sort(function(t,i){var o=n._findPolarAngle(n.anchorPoint,t),h=n._findPolarAngle(n.anchorPoint,i);return h>o?-1:o>h?1:0})},_checkPoints:function(n,t,i){var o,h=this._findPolarAngle(n,t),r=this._findPolarAngle(n,i);return h>r?(o=h-r,!(o>180)):r>h?(o=r-h,o>180):!0},getHull:function(){var n,t,i=[];if(this.reverse=this.points.every(function(n){return n.x<0&&n.y<0}),n=this._sortPoints(),t=n.length,3>t)return n.unshift(this.anchorPoint),n;for(i.push(n.shift(),n.shift());;){var o,h,r;if(i.push(n.shift()),o=i[i.length-3],h=i[i.length-2],r=i[i.length-1],this._checkPoints(o,h,r)&&i.splice(i.length-2,1),0==n.length){if(t==i.length){var e=this.anchorPoint;return i=i.filter(function(n){return!!n}),i.some(function(n){return n.x==e.x&&n.y==e.y})||i.unshift(this.anchorPoint),i}n=i,t=n.length,i=[],i.push(n.shift(),n.shift())}}}},"function"==typeof define&&define.amd&&define(function(){return ConvexHullGrahamScan}),"undefined"!=typeof module&&(module.exports=ConvexHullGrahamScan);
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