forked from: ドロネー図（分割）

/**
 * Copyright asou_jp ( http://wonderfl.net/user/asou_jp )
 * MIT License ( http://www.opensource.org/licenses/mit-license.php )
 * Downloaded from: http://wonderfl.net/c/6bOS
 */

// forked from fumix's ドロネー図（分割）
/**
画面を適当にクリックすると3クリック以降、ポイントと線がひかれます。
線は交差すること無くひかれていきます

参照：
ドロネー図
http://ja.wikipedia.org/wiki/ドロネー図
ドロネー図の作図方法
http://homepage3.nifty.com/endou/tips/04/tips33.htm
外接円
http://wonderfl.net/code/ad8b6c5010abdb44d3e34d3a7cd06a200b35175d
.fla2「YuruYurer」（195P）
http://www.amazon.co.jp/dp/4862670717
*/
package {
    import flash.display.Bitmap;
    import flash.display.BitmapData;
    import flash.events.MouseEvent;
    import flash.display.StageQuality;
    import flash.display.StageScaleMode;
    import flash.display.Graphics;
    import flash.display.Sprite;
    import flash.events.Event;
    import flash.system.Security;
    import flash.display.StageAlign;
    [SWF(width = 465, height = 465, backgroundColor = 0x0, frameRate = 60)]

    public class Delaunay extends Sprite {

        //----------------------------------------
        //VARIABLES
        
        //点群
        private var _points : Array;
        //三角形の集まり
        private var _triangles : Array;
        //キャンバス
        private var _canvas : Sprite;
        //background
        private var _background:BitmapData;

        /*
         * コンストラクタ
         */
        public function Delaunay() {
            //Security.allowDomain("*");
            //Security.allowDomain("planet-ape.net");
            //Security.allowDomain("wonderfl.net");
            //Security.allowDomain("swf.wonderfl.net");
            //初期化
            addEventListener(Event.ADDED_TO_STAGE, _initialize);
        }

        /*
         * 初期化
         */
        private function _initialize(event : Event) : void {
            removeEventListener(Event.ADDED_TO_STAGE, _initialize);
            
            stage.scaleMode = StageScaleMode.NO_SCALE;
            stage.align = StageAlign.TOP_LEFT;
            
            var stageWidth : Number = stage.stageWidth;
            var stageHeight : Number = stage.stageHeight;
            //背景カラー
            _background = new BitmapData(stageWidth , stageHeight, false, 0x0);
            addChild(new Bitmap(_background));

            //ドロー用
            _canvas = addChild(new Sprite()) as Sprite;

            _points = new Array();
            _triangles = new Array();
            
            //ステージの大きさの三角形2つを用意
            _points.push(new Node(0, 0, 0));
            _points.push(new Node(1, stageWidth, 0));
            _points.push(new Node(2, stageWidth, stageHeight));
            _points.push(new Node(3, 0, stageHeight));
            _triangles.push(new Triangle(_points[0], _points[1], _points[2]));
            _triangles.push(new Triangle(_points[0], _points[2], _points[3]));

            addEventListener(Event.ENTER_FRAME, _updateHandler);
            stage.addEventListener(MouseEvent.MOUSE_UP, _stageMouseUpHandler);
        }

        /*
         * アップデート
         */
        private function _updateHandler(event : Event) : void {
            _interaction();
            _draw();
        }

        /*
         * インタラクション
         */
        private function _interaction() : void {
            //一時保持の三角形群
            var localTriangles : Array = new Array();
            //辺
            var edges : Array;
            //多角形
            var polygon : Array;
            //ポイント群ループ
            for (var k : int = 4;k < _points.length;k++) {
                var node : Node = _points[k];
                localTriangles = new Array();
                edges = new Array();
            
                for (var i : String in _triangles) {
                    //点が外接円
                    var tri : Triangle = _triangles[i];
                    if(inOuterCircle(node.point.x, node.point.y, tri)) {
                        edges.push(new Edge(tri.node0, tri.node1));
                        edges.push(new Edge(tri.node1, tri.node2));
                        edges.push(new Edge(tri.node2, tri.node0));
                    } else {
                        localTriangles.push(tri);                        
                    }                
                }
                //edgesからpolygonを作る（重複辺の削除
                polygon = new Array();
                for (i in edges) {
                    var edge0 : Edge = edges[i];
                    //重複チェック
                    var flg : Boolean = false;
                    for (var j : String in polygon) {
                        var edge1 : Edge = polygon[j];
                        if(judgeEdges(edge0, edge1)) {
                            flg = true;
                            polygon.splice(j, 1);
                            break;                        
                        }
                    }
                    //データが存在しない場合は追加
                    if(!flg) polygon.push(edges[i]);
                }
                //polygonから三角形を作って挿入
                for (i in polygon) {
                    var tri1 : Triangle = new Triangle(polygon[i].node0, polygon[i].node1, node);
                    localTriangles.push(tri1);
                }
            }
            if(localTriangles.length > 1) _triangles = localTriangles;
        }

        /*
         * 同じ辺かどうかの判定
         */
        private function judgeEdges(edge : Edge, edge0 : Edge) : Boolean {            
            if(edge.node0.id == edge0.node0.id && edge.node1.id == edge0.node1.id) {
                return true;                
            }
            if(edge.node1.id == edge0.node0.id && edge.node0.id == edge0.node1.id) {
                return true;
            }
            return false;
        }

        /*
         * 描画
         */
        private function _draw() : void {
            var g : Graphics = _canvas.graphics;
            var offset : Number = 0;
            g.clear();
            g.lineStyle(1, 0xffffff);
            
            //三角形群のループ
            for (var i : int = 0;i < _triangles.length;i++) {
                var tri : Triangle = _triangles[i];
                //四隅のポイントを含む三角形は描画しない
                if(!(tri.node0.id == 0 || tri.node1.id == 0 || tri.node2.id == 0 ||
                    tri.node0.id == 1 || tri.node1.id == 1 || tri.node2.id == 1 ||
                    tri.node0.id == 2 || tri.node1.id == 2 || tri.node2.id == 2 ||
                    tri.node0.id == 3 || tri.node1.id == 3 || tri.node2.id == 3)
                ){
                g.moveTo(tri.node0.point.x + offset, tri.node0.point.y + offset);
                g.lineTo(tri.node1.point.x + offset, tri.node1.point.y + offset);
                g.lineTo(tri.node2.point.x + offset, tri.node2.point.y + offset);
                g.lineTo(tri.node0.point.x + offset, tri.node0.point.y + offset);
                g.beginFill(0xFF0000);
                g.drawCircle(tri.node0.point.x + offset, tri.node0.point.y + offset, 3);
                g.drawCircle(tri.node1.point.x + offset, tri.node1.point.y + offset, 3);
                g.drawCircle(tri.node2.point.x + offset, tri.node2.point.y + offset, 3);
                g.endFill();                    
                }
            }
        }

        /*
         * 外接円の内か外か
         */
        static function inOuterCircle(x : Number,y : Number,tri : Triangle) : Boolean {
            var node0 : Node = tri.node0;
            var node1 : Node = tri.node1;
            var node2 : Node = tri.node2;
            
            var d : Number = (node0.point.x * node0.point.x + node0.point.y * node0.point.y - x * x - y * y) * ((node1.point.x - x) * (node2.point.y - y) - (node2.point.x - x) * (node1.point.y - y)) + (node1.point.x * node1.point.x + node1.point.y * node1.point.y - x * x - y * y) * ((node2.point.x - x) * (node0.point.y - y) - (node2.point.y - y) * (node0.point.x - x)) + (node2.point.x * node2.point.x + node2.point.y * node2.point.y - x * x - y * y) * ((node0.point.x - x) * (node1.point.y - y) - (node0.point.y - y) * (node1.point.x - x));
            return ( (node1.point.x - node0.point.x) * (node2.point.y - node0.point.y) - (node1.point.y - node0.point.y) * (node2.point.x - node0.point.x) > 0 ) ? d > 0 : d <= 0;
        }

        /*
         * マウスクリック時
         */
        private function _stageMouseUpHandler(event : MouseEvent) : void {
            _points.push(new Node(_points.length, mouseX, mouseY));
        }
    }
}
class Triangle {
    private var _node0 : Node;
    private var _node1 : Node;
    private var _node2 : Node;
    
    public function Triangle(node0:Node,node1:Node,node2:Node):void {
        _node0 = node0;
        _node1 = node1;
        _node2 = node2;
    }
    
    public function get node0() : Node {
        return _node0;
    }
    
    public function get node1() : Node {
        return _node1;
    }
    
    public function get node2() : Node {
        return _node2;
    }
}
import flash.geom.Point;
class Node {
    private var _id : int;
    private var _point : Point;

    public function Node(id:int,x:Number,y:Number) {
        _id = id;
        _point = new Point(x,y);
    }
    
    public function get id() : int {
        return _id;
    }
    
    public function get point() : Point {
        return _point;
    }
}
class Edge {
    private var _node0 : Node;
    private var _node1 : Node;
    
    public function Edge(node0:Node,node1:Node):void {
        _node0 = node0;
        _node1 = node1;
    }
    
    public function get node0() : Node {
        return _node0;
    }
    
    public function get node1() : Node {
        return _node1;
    }
}