forked from: 二つのうねうね

/**
 * Copyright hakerlab ( http://wonderfl.net/user/hakerlab )
 * MIT License ( http://www.opensource.org/licenses/mit-license.php )
 * Downloaded from: http://wonderfl.net/c/iNN3
 */

// forked from fumix's 二つのうねうね
package 
{
    import flash.display.Sprite;
    import flash.display.Stage;
    import flash.events.Event;
    
    /**
     * ...
     * @author DefaultUser (Tools -> Custom Arguments...)
     */
    [SWF(width = "465", height = "465", frameRate = "30", backgroundColor = "#ffffff")]
    public class Main extends Sprite 
    {
        
        
        
        
        /**
         * コンストラクタ
         */
        public function Main():void 
        {
            if (stage) init();
            else addEventListener(Event.ADDED_TO_STAGE, init);
            var r1:ribbon = new ribbon(false,0xCCCCCC,18);
            var r2:ribbon = new ribbon(true,0xAAAAAA,15);
            r1.x = stage.stageWidth / 2;
            r2.x = stage.stageWidth / 2+4;
            addChild(r1);
            addChild(r2);
        }
    }
    
}
    import flash.display.Sprite;
    import flash.display.Stage;
    import flash.events.Event;
    
    /**
     * ...
     * @author DefaultUser (Tools -> Custom Arguments...)
     */
    class ribbon extends Sprite 
    {
        private const MAXNUMBER:int = 100;
        private const WIDTH:int = 14;
        
        private var widthPiece:Number;
        private var offsetX:Number;
        private var offsetY:Number;
        private var color:uint;
        
        private var rad1:Number;
        private var rad2:Number;
        private var drad1:Number;

        private var rollDirection:int;
        
        
        private var Sprites:Array;
        
        
        
        
        /**
         * ウネウネするリボン
         * @リボンの振り幅        _widthPiece
         * @x座標のオフセット    _offsetX
         * @y座標のオフセット    _offsetY
         * @y回転方向（右左）    _roll
         */
        public function ribbon(_roll:Boolean=true, _color:uint=0x000000,_widthPiece:Number=15,_offsetX:Number=0,_offsetY:Number=0):void 
        {
            //初期値設定
            if (_roll) rollDirection = 1;
            else rollDirection = -1;
            color = _color;
            widthPiece = _widthPiece;
            offsetX = _offsetX;
            offsetY = _offsetY;

            if (stage) init();
            else addEventListener(Event.ADDED_TO_STAGE, init);
            
        }
        
        /**
         * 初期処理
         * @param    e
         */
        private function init(e:Event = null):void 
        {
            removeEventListener(Event.ADDED_TO_STAGE, init);
            
            //リボンの振りとうねりの開始角度を決定
            rad1 = Math.floor(Math.random() * 36) * 10;
            rad2 = Math.floor(Math.random() * 36) * 10;
            drad1 = 3;

            //ダミースプライト生成
            var i1:Number = MAXNUMBER;
            Sprites = new Array();
            while (i1--) {
               Sprites.push({x:offsetX, y:((stage.stageHeight+30) /MAXNUMBER) *i1+offsetY - 15});
            }
            addEventListener(Event.ENTER_FRAME, onEnterFrame);
            // entry point
        }

        /**
         * ループ処理
         * @param    e
         */
        private function onEnterFrame(e:Event):void 
        {
            headTrail();
            trail(0,MAXNUMBER, 0.9);
            drawPolygon();
        }
        
        
        /**
         * 最初のスプライトの動き
         */
        private function headTrail():void
        {
            rad1 += drad1;
            rad2 += 2;
            if(rad1 >360){
                rad1 = rad1 - 360;
                drad1 = Math.random()*4+2;//目標周期をランダムに決定（2～6）
            }
            if(rad2 >360){
                rad2 = rad2 - 360;
            }
            Sprites[0].x = Math.sin(rollDirection*rad1 * Math.PI/180)*widthPiece+offsetX;
        }
        /**
         * 先頭の点以外の処理
         * @param    st
         * @param    end
         * @param    rate
         */
        private function trail(st:int,end:int,rate:Number):void
        {
            for (var i:int = (end - 1); i > st; i-- ) {
                Sprites[i].x = Sprites[(i - 1)].x;
            }
        }
        
        /**
         * ポリゴンの描写
         */
        private function drawPolygon():void
        {
            
            var i1:int = MAXNUMBER;
            graphics.clear();
            while (--i1) {
                graphics.beginFill(color);
                graphics.lineStyle(0, color, 1);
                var w1:Number = WIDTH*Math.cos(rollDirection*(rad2+i1*2+45) * Math.PI/180)/2;
                graphics.moveTo(Sprites[i1].x-w1, Sprites[i1].y-w1);
                graphics.lineTo(Sprites[i1].x + w1, Sprites[i1].y + w1);
                
                var w2:Number = WIDTH*Math.cos(rollDirection*(rad2+i1*2+45) * Math.PI/180)/2;
                graphics.lineTo(Sprites[(i1-1)].x+w2, Sprites[(i1-1)].y+w2);
                graphics.lineTo(Sprites[(i1-1)].x-w2, Sprites[(i1-1)].y-w2);
                graphics.lineTo(Sprites[i1].x-w1, Sprites[i1].y-w1);
                graphics.endFill();
            }            
        }
    }