forked from: 万有引力

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

package{
    import flash.events.Event;
    import flash.display.Sprite;
    
    public class FlashTest extends Sprite{
        
        private var ballArr:Array;
        private var ballNum:int = 200;;
    
    public function FlashTest(){
        init();
    }
    
    private function init():void{
        ballArr = new Array();
        
        for(var i:int = 0; i < ballNum; i++){
        var ball:Ball = new Ball();
        var radian:Number = 360 / (ballNum -1) * i * Math.PI / 180;
        ball.x = 232 + Math.cos(radian) * 100;
        ball.y = 232 + Math.sin(radian) * 100;
        ball.mass = 1;
        addChild(ball);
        ballArr.push(ball);
        }//for
       addEventListener(Event.ENTER_FRAME, onEnter);
        
    }//init    
    private function onEnter(event:Event):void{
        ballBakuhatu();
    }
    private function ballBakuhatu():void{
        for(var i:int = 0; i < ballNum; i++){
            var ball:Ball = ballArr[i];
            ball.x += ball.vx;
            ball.y += ball.vy;
        }
        for(i = 0; i < ballNum - 1; i++){
            var partA:Ball = ballArr[i];
            for(var j:int = i + 1; j < ballNum; j++){
               var partB:Ball = ballArr[j];
               gravitate(partA, partB); 
            }
        }
    }

    
    private function gravitate(partA:Ball, partB:Ball):void{
        var dx:Number = partB.x - partA.x;
        var dy:Number = partB.y - partA.y;
        var distSQ:Number = dx * dx + dy * dy;
        var dist:Number = Math.sqrt(distSQ);
        
        var force:Number = partA.mass * partB.mass / distSQ;
        var ax:Number = force * dx / dist;
        var ay:Number = force * dy / dist;
        partA.vx += ax / partA.mass;
        partA.vy += ay / partA.mass;
        partB.vx -= ax / partB.mass;
        partB.vy -= ay / partB.mass;
        
    }



    }//class
}//package

import flash.display.Sprite;
class Ball extends Sprite{
    public var vx:Number = 0;
    public var vy:Number = 0;
    public var mass:Number = 1;
    public var radias:int;
    public var color:uint;
    
    function Ball(radias:int = 10, color:uint = 0xcccccc){
        this.radias = radias;
        
        graphics.beginFill(color);
        graphics.drawCircle(0, 0, radias);
        graphics.endFill();
    }

}




// forked from takenosin's 万有引力
// forked from takenosin's パーティクル
/*package {
    import flash.display.Sprite;
    import flash.events.Event;
    
    public class ClassName extends Sprite {
        
        private var Particles:Array;
        private var numParticles:uint = 30;
        
        public function ClassName() {
            // write as3 code here..          
            Particles = new Array();
            for(var i:uint = 0; i < numParticles; i++){
                var Particle:Ball = new Ball(5);
                Particle.x = Math.random() * stage.stageWidth;
                Particle.y = Math.random() * stage.stageHeight;
                Particle.mass = 1;
                addChild(Particle);
                Particles.push(Particle);
            }
            
            addEventListener(Event.ENTER_FRAME,onEnterFrame);
            
        }
        
        private function onEnterFrame(event:Event):void{
        for(var i:uint = 0; i < numParticles; i++){
        var Particle:Ball = Particles[i];
            Particle.x += Particle.vx;
            Particle.y += Particle.vy;
            }
            
            for(i = 0; i < numParticles - 1; i++){
                var PartA:Ball = Particles[i];
                for(var j:uint = i + 1; j < numParticles; j++){
                    var PartB:Ball = Particles[j];
                    gravitate(PartA,PartB);
                }
            }          
        }
        private function gravitate(PartA:Ball,PartB:Ball):void{
            var dx:Number = PartB.x - PartA.x;
            var dy:Number = PartB.y - PartA.y;
            var distSQ:Number = dx * dx + dy * dy;
            var dist:Number = Math.sqrt(distSQ);
            var force:Number = PartA.mass * PartB.mass / distSQ;
            var ax:Number = force * dx / dist;
            var ay:Number = force * dy / dist;
            PartA.vx += ax / PartA.mass;
            PartA.vy += ay / PartA.mass;
            PartB.vx += ax / PartB.mass;
            PartB.vy += ay / PartB.mass;
        }
    }
}


import flash.display.Sprite;
class Ball extends Sprite{
    
    public var radius:Number;
    private var color:uint;
    public var vx:Number = 0;
    public var vy:Number = 0;
    public var mass:Number = 1;
    
    public function Ball(radius:Number=40,color:uint=0x66ffff){
        this.radius = radius;
        this.color = color;
        
        graphics.beginFill(color);
        graphics.drawCircle(0,0,radius);
        graphics.endFill();
    }
}*/