Voronoi-Test

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my first voronoi experiment 
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by cid 24 Jun 2009

Tags

voronoi 超炫的線條效果
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/**
 * Copyright cid ( http://wonderfl.net/user/cid )
 * MIT License ( http://www.opensource.org/licenses/mit-license.php )
 * Downloaded from: http://wonderfl.net/c/a3XE
 */

//------------------------------------------------------------ 
// my first voronoi experiment 
//------------------------------------------------------------ 

package 
{ 
import flash.display.*; 
import flash.events.*; 
import net.hires.debug.Stats;  

[SWF(backgroundColor=0xffffff, frameRate=50)] 

public class Voronoi extends Sprite 
{ 
    public var maxSpeed:Number = 2; 
    public var numDots:int = 100; 
     
    private var dots:Vector.<Dot> = new Vector.<Dot>; 
    private var PI2:Number = 2 * Math.PI; 
    private var distance:Array = []; 
    private var sx:Array = []; 
    private var sy:Array = []; 
    private var ex:Array = []; 
    private var ey:Array = []; 
    private var dotNum:int = 0; 
    private var width_:Number; 
    private var height_:Number; 
    private var storage:int; 

     
    public function Voronoi() 
    { 
        addEventListener("addedToStage", init); 
    } 

     
    public function init(e:Event):void{ 
        removeEventListener("addedToStage", init); 
        var stats:Stats = new Stats(); 
        stats.alpha = 0.5; 
        addChild(stats); 

        width_ = stage.stageWidth; 
        height_ = stage.stageHeight; 
         
        for (var i:int=0; i<numDots; i++) { 
            addDot(); 
        } 

        calcDots();         
        addEventListener("enterFrame", onEnterFrame); 
    } 

     
    private function addDot():void 
    { 
        var dot:Dot = new Dot(); 
        dot.vx = (Math.random()-0.5) * maxSpeed; 
        dot.vy = (Math.random()-0.5) * maxSpeed; 
        dots.push(dot); 
         
        dotNum ++; 
        storage = dotNum + 4; 
    } 


    private function onEnterFrame(e:Event):void 
    { 
        moveDots(); 
        update(); 
    } 


    public function calcDots():void{ 
        for each (var dot:Dot in dots){ 
            dot.x = Math.random() * width_; 
            dot.y = Math.random() * height_; 
        } 
    } 

    public function moveDots():void{ 
        for each (var dot:Dot in dots){ 
            dot.x += dot.vx; 
            if (dot.x > width_) dot.x -= width_ 
            else if (dot.x < 0) dot.x += width_; 

            dot.y += dot.vy; 
            if (dot.y > height_) dot.y -= height_ 
            else if (dot.y < 0) dot.y += height_; 
        } 
    } 

     
    public function update():void{ 
        setVoronoi(); 
        drawVoronoi(); 
    } 


    private function setVoronoi():void 
    { 
        var i:int, j:int, k:int, m:int, n:int; 
        var a:Number, b:Number, a0:Number, b0:Number, a1:Number, b1:Number, x:Number, y:Number, 
            x0:Number, y0:Number, x1:Number, y1:Number; 
         
        for (i=0; i<dotNum; i++) { 
            x0 = dots[i].x; 
            y0 = dots[i].y; 
            n = i * storage + i + 1; 
             
            for (j=i+1; j<dotNum; j++) { 
                x1 = dots[j].x; 
                y1 = dots[j].y; 
                 
                if (x1 == x0) { 
                    a = 0; 
                } else if (y1 == y0) { 
                    a = 10000; 
                } else { 
                    a = -1/((y1-y0)/(x1-x0)); 
                } 
                b = (y0+y1)/2-a*(x0+x1)/2; 
                 
                if (a>-1 && a<=1) { 
                    sx[n] = 0; 
                    sy[n] = a * sx[n] + b; 
                    ex[n] = width_ - 1; 
                    ey[n] = a * ex[n] + b; 
                } else { 
                    sy[n] = 0; 
                    sx[n] = (sy[n]-b)/a; 
                    ey[n] = height_ - 1; 
                    ex[n] = (ey[n]-b)/a; 
                } 
                n++; 
            } 
             
            sx[n] = 0; 
            sy[n] = 0; 
            ex[n] = width_; 
            ey[n] = 0; 
            n++; 
            sx[n] = .1; 
            sy[n] = 0; 
            ex[n] = 0; 
            ey[n] = height_; 
            n++; 
            sx[n] = width_; 
            sy[n] = 0; 
            ex[n] = width_ - 0.1; 
            ey[n] = height_; 
            n++; 
            sx[n] = 0; 
            sy[n] = height_; 
            ex[n] = width_; 
            ey[n] = height_; 
        } 

        for (i=0; i<dotNum; i++) { 
            x0 = dots[i].x; 
            y0 = dots[i].y; 
            for (j=0; j<dotNum+4; j++) { 
                if (j != i) { 
                    if (j>i) { 
                        n = i * storage + j; 
                    } else { 
                        n = j * storage + i; 
                    } 
                    if (sx[n] >- Number.MAX_VALUE) { 
                        a0 = (ey[n] - sy[n]) / (ex[n] - sx[n]); 
                        b0 = sy[n] - a0 * sx[n]; 
                        for (k=i+1; k<dotNum+4; k++) { 
                            if (k != j) { 
                                m = i * storage + k; 
                                if (sx[m]>-Number.MAX_VALUE) { 
                                    a1 = (ey[m]-sy[m])/(ex[m]-sx[m]); 
                                    b1 = sy[m]-a1*sx[m]; 
                                    x = -(b1-b0)/(a1-a0); 
                                    y = a0*x+b0; 
                                    if ((a0*x0+b0-y0)*(a0*sx[m]+b0-sy[m])<0) { 
                                        sx[m] = x; 
                                        sy[m] = y; 
                                    } 
                                    if ((a0*x0+b0-y0)*(a0*ex[m]+b0-ey[m])<0) { 
                                        if (sx[m] == x) { 
                                            sx[m] = -Number.MAX_VALUE; 
                                        } else { 
                                            ex[m] = x; 
                                            ey[m] = y; 
                                        } 
                                    } 
                                } 
                            } 
                        } 
                    } 
                } 
            } 
        } 
    } 

     
    private function drawVoronoi():void{ 
        var i:int, j:int, n:int; 

        graphics.clear(); 
        graphics.lineStyle(0, 0x003366, 1); 
                 
        for (i=0; i<dotNum; i++) { 
            n = i * storage + i + 1; 
            for (j=i+1; j<dotNum+4; j++) { 
                if (sx[n]>-Number.MAX_VALUE) { 
                    graphics.moveTo(sx[n], sy[n]); 
                    graphics.lineTo(ex[n], ey[n]); 
                } 
                n++; 
            } 
        } 
    } 

} 
} 


class Dot{ 
    public var x:Number; 
    public var y:Number; 
    public var vx:Number; 
    public var vy:Number; 
}