Fiber

by tnRaro 28 Dec 2014

Embed

/**
 * Copyright tnRaro ( http://wonderfl.net/user/tnRaro )
 * GNU General Public License, v3 ( http://www.gnu.org/licenses/quick-guide-gplv3.html )
 * Downloaded from: http://wonderfl.net/c/yiVB
 */

package {
    import flash.display.Sprite;
    import flash.display.Graphics;
    import flash.events.TimerEvent;
    import flash.events.MouseEvent;
    import flash.utils.Timer;
    import flash.geom.Point;
    public class FlashTest extends Sprite {
        
        private var g:Graphics;
        private var timer:Timer;
        
        private var f:Fiber;
        
        private var mx:Number;
        private var my:Number;
        
        public function FlashTest() {
            // write as3 code here..
            
            g = this.graphics;
            
            f = new Fiber(200, 10);
            
            mx = stage.stageWidth * .5;
            my = stage.stageHeight * .5;
            
            timer = new Timer(20);
            timer.addEventListener(TimerEvent.TIMER, te);
            timer.start();
            
            stage.addEventListener(MouseEvent.MOUSE_MOVE, me);
        }
        
        private function me(e:MouseEvent):void{
            mx = e.stageX;
            my = e.stageY;
            
            f.x = mx;
            f.y = my;
        }
        
        private function te(e:TimerEvent):void{
            g.clear();
            
            f.applyForce(new Point(0, 2));
            f.calibrate();
            
            g.lineStyle(10, 0x838383);
            g.moveTo(f.x, f.y);
            for each(var p:Point in f.pointListWithoutZero){
                g.lineTo(p.x, p.y);
            }
        }
    }
}
import flash.geom.Point;
	
	/**
	 * ...
	 * @author popung, [fork]tnraro.com
	 */
	class Fiber 
	{
		private const C:Number = 1;
		
		private var p:Vector.<Point>;
		private var v:Vector.<Point>;
		private var len:Number;
		
		/**
		* ファイバ
		* @param	length	ファイバの長さ
		* @param	segment	区分点の数
		*/
		public function Fiber(length:Number, segment:int=8):void 
		{
			super();
			
			p = new Vector.<Point>();
			v = new Vector.<Point>();
			len = length/segment;
			
			for (var i:int = 0; i <= segment; i++) 
			{
				p.push(new Point(0, len * i));
				v.push(new Point());
			}
		}
		
		/**
		* 力(Vector)をあわせる。
		* @param	force	vector
		*/
		public function applyForce(force:Point):void
		{
			for (var i:int = 1; i < v.length; i++) 
			{
				v[i] = v[i].add(force);
				p[i] = p[i].add(v[i]);
			}
		}
		
		/**
		* ファイバを調整する。
		* @param	step	step
		*/
		public function calibrate(step:int=20):void
		{
			var i:int, j:int;
			for (j = 0; j < step; j++)
			{
				for (i = 1; i < p.length; i++) 
				{
					var p1:Point = p[i - 1];
					var p2:Point = p[i];
					
					var del:Point = p2.subtract(p1);
					var err:Number = del.length - len;
					
					if (i != 1)
					{
						//del.normalize(err * c / 2);
						del.normalize(err * C * .5);
						p[i] = p2.subtract(del);
						p[i - 1] = p1.add(del);
						
						v[i] = v[i].subtract(del);
						v[i-1] = v[i-1].add(del);
					}
					else
					{
						del.normalize(err * C);
						p[i] = p2.subtract(del);
						v[i] = v[i].subtract(del);
					}
				}
			}
		}
		
		/**
		* getPoint
		*/
		public function get pointList():Vector.<Point>
		{
			return p;
		}
		/**
		* getPoint
		*/
		public function get pointListWithoutZero():Vector.<Point>
		{
			return p.slice(1);
		}
		
		public function get x():Number { return p[0].x }
		public function get y():Number { return p[0].y }
		public function set x(value:Number):void { p[0].x=value }
		public function set y(value:Number):void { p[0].y=value }
	}