引力・斥力

by cpu_t 20 Jun 2010

Tags

物理演算
Embed

/**
 * Copyright cpu_t ( http://wonderfl.net/user/cpu_t )
 * MIT License ( http://www.opensource.org/licenses/mit-license.php )
 * Downloaded from: http://wonderfl.net/c/3z8a
 */

package
{
    import flash.display.Sprite;
    import flash.events.MouseEvent;
    import flash.events.Event;
    public class FlashTest extends Sprite
    {
        public function FlashTest()
        {
        		this.graphics.beginFill(0);
        		this.graphics.drawRect(0,0,stage.stageWidth,stage.stageHeight);
            stage.addEventListener(MouseEvent.MOUSE_DOWN,mouseDownHandler);
            addEventListener(Event.ENTER_FRAME,enterFrameHandler);
        }
        
        private var head:Node;
        private var tail:Node;
        
        private function mouseDownHandler(e:MouseEvent):void
        {
        		var node:Node=addNode();
        		addChild(node);
        		node.x=mouseX;
        		node.y=mouseY;
        }
        
        private function addNode():Node
        {
        		var node:Node=new Node();
        		if(head==null)
        		{
        			node.prev=node.next=node;//
        			head=tail=node;
        		}
        		else
        		{
        			node.next=head;//
        			node.prev=tail;
        			tail=tail.next=node;
        			head.prev=tail;//
        		}
        		return node;
        }
        
        private var cnt:Number=0;
        private function enterFrameHandler(e:Event):void
        {
        		Node.equil=30+Math.sin((cnt++)/180*Math.PI*3)*20;
        		var node:Node=head;
        		do
        		{
        			node.update();
        			if(node.isDead)
        			{
        				if(node.prev==tail)
        				{
        					head=node.next;
        					tail.next=head;
        				}
        				else node.prev.next=node.next;
        				if(node.next==head)
        				{
        					tail=node.prev;
        					head.prev=tail;
        				}
        				else node.next.prev=node.prev;
        				removeChild(node);
        			}
        			node=node.next;
        		}
        		while(node!=head);
        }
    }
}

import flash.display.Sprite;
import frocessing.color.ColorHSV;
class Node extends Sprite
{
	public function Node()
	{
		var color:ColorHSV=new ColorHSV(Math.random()*360);
		this.graphics.beginFill(color.value);
		this.graphics.drawCircle(0,0,10);
		this.addChild(line=new Sprite());
	}
	private static const rev:Number=0.2;
	public static var equil:Number=20;
	public var prev:Node;
	public var next:Node;
	public var isDead:Boolean=false;
	private var line:Sprite;
	private var vx:Number=0;
	private var vy:Number=0;
	public function update():void
	{
		vx*=0.85; vy*=0.85;
		var dis:Number;
		if(prev!=null)
		{
			dis=Math.sqrt((prev.x-x)*(prev.x-x)+(prev.y-y)*(prev.y-y));
			if(dis!=0)
			{
				vx+=(prev.x-x)/dis*(dis-equil)*rev;
				vy+=(prev.y-y)/dis*(dis-equil)*rev;
			}
		}
		if(next!=null)
		{
			dis=Math.sqrt((next.x-x)*(next.x-x)+(next.y-y)*(next.y-y));
			if(dis!=0)
			{
				vx+=(next.x-x)/dis*(dis-equil)*rev;
				vy+=(next.y-y)/dis*(dis-equil)*rev;
			}
		}
		x+=vx; y+=vy;
		if(x<0)
		{
			x*=-1;
			vx*=-1;
		}
		else if(x>=stage.stageWidth)
		{
			x=stage.stageWidth*2-x;
			vx*=-1;
		}
		if(y<0)
		{
			y*=-1;
			vy*=-1;
		}
		else if(y>=stage.stageHeight)
		{
			y=stage.stageHeight*2-y;
			vy*=-1;
		}
		if(prev!=null)
		{
			line.graphics.clear();
			line.graphics.lineStyle(-1,0xFFFFFF);
			line.graphics.moveTo(0,0);
			line.graphics.lineTo(prev.x-x,prev.y-y);
		}
		if(false)isDead=true;
	}
}