forked from: forked from: ちりちりな何か

by alexnotkin 07 Apr 2013

• Forked from demouth's forked from: ちりちりな何か
• Diff: 4
• Related works: 10

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BitmapData Dynamic Interaction algorithm animation cool particles インタラクティブ
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/**
 * Copyright alexnotkin ( http://wonderfl.net/user/alexnotkin )
 * MIT License ( http://www.opensource.org/licenses/mit-license.php )
 * Downloaded from: http://wonderfl.net/c/3Q28
 */

// forked from demouth's forked from: ちりちりな何か
// forked from demouth's ちりちりな何か
// forked from demouth's forked from: ひも的な何か
// forked from demouth's ひも的な何か
package  
{
    import flash.display.Graphics;
    import flash.display.Sprite;
    import flash.display.Stage;
    import flash.display.StageAlign;
    import flash.display.StageScaleMode;
    import flash.events.Event;
    
    [SWF(frameRate='60')] 
    public class Main extends Sprite
    {
        protected var joints:Vector.<Vector.<Joint>> = new Vector.<Vector.<Joint>>();
        protected var fric:Number = 0.01;
        protected var dis:Number = 15;
        protected var range:int = 7;//前後に影響を与える範囲
        protected var num:int = 50;
        protected var lineNum:int = 100;
        
        public function Main() 
        {
            if (this.stage) this.init()
            else this.addEventListener(Event.ADDED_TO_STAGE , this.init);
        }
        
        protected function init(event:Event = null):void
        {
            this.stage.align = StageAlign.TOP_LEFT;
            this.stage.scaleMode = StageScaleMode.NO_SCALE;
            for (var i:int = 0; i < this.lineNum; i++) this.joints.push(this.create());
            this.addEventListener(Event.ENTER_FRAME , this.enterFrameHandler);
        }
        
        protected function create():Vector.<Joint>
        {
            var num:Number = this.num;
            var joints:Vector.<Joint> = new Vector.<Joint>();
            for (var i:int = 0; i < num; i++) joints.push(new Joint());
            return joints;
        }
        
        private function enterFrameHandler(event:Event):void
        {
            this.graphics.clear();
            
            for (var i:int = 0; i < this.lineNum; i++) 
            {
                this.calc(this.joints[i]);
                this.move(this.joints[i],i/this.lineNum);
                this.draw(this.joints[i]);
            }
        }
        
        private function calc(joints:Vector.<Joint>):void
        {
            var l:int = joints.length;
            for (var i:int = 0; i < l; i++) 
            {
                if (i == 0)
                {
                    joints[0].x = this.stage.mouseX;
                    joints[0].y = this.stage.mouseY;
                    continue;
                }
                
                var b:int = this.range;
                var a:int = this.range;
                var now:Joint = joints[i];
                
                for (var j:int = i-b; j < i+a+1; j++) 
                {
                    if (j >= 0 && l > j && j != i)
                    {
                        var t:Joint = joints[j];
                        
                        var angle:Number = Math.atan2(now.y-t.y, now.x-t.x);
                        now.sx -= Math.cos(angle) * 6 * Math.random()*2 ;
                        now.sy -= Math.sin(angle) * 6 * Math.random()*2;
                    }
                }
            }
        }
        
        private function move(joints:Vector.<Joint> , spring:Number):void
        {
            var l:int = joints.length;
            for (var i:int = 0; i < l; i++) 
            {
                var now:Joint = joints[i];
                if(i!=0)now.sy += 0.2;
                now.x += now.sx * this.fric;
                now.y += now.sy * this.fric;
                
                if (i == 0) continue;
                var b:Joint = joints[i-1];
                
                var angle:Number = Math.atan2(b.y - now.y, b.x - now.x);
                now.x = b.x - Math.cos(angle) * this.dis;
                now.y = b.y - Math.sin(angle) * this.dis;
                
                now.sx *= spring;
                now.sy *= spring;
            }
        }
        
        private function draw(joints:Vector.<Joint>):void
        {
            var g:Graphics = this.graphics;
            var l:int = joints.length;
            
            for (var i:int = 0; i < l; i++) 
            {
                g.beginFill(0);
                g.drawCircle(joints[i].x, joints[i].y, (i<7)?1:joints[i].sx*0.02+1);
                g.endFill();
            }
            
        }
    }

}

class Joint
{
    public var x:Number = 0;
    public var y:Number = 0;
    public var sx:Number = 0;
    public var sy:Number = 0;
}