アワブクロック

黒いエリアを探して、そこに円が置けるなら置きます。

ランダムに座標を生成→その点が黒か否かを判別、黒なら、半径rの12点を取得し、それらがすべて黒なら、白い円を描く
を、数百回くりかえします。
最初の「ランダムに座標を生成」がほぼ工夫がない。事前に荒く見て、真っ白じゃない部分のみ、走査するなどすれば、計算コストが減るかも。

アワブクロック – wonderfl build flash online

[sourcecode language=”as3″]
package
{
import flash.display.Sprite;
import flash.events.Event;

/**
* …
* @author umhr
*/
public class WonderflMain extends Sprite
{

public function WonderflMain()
{
init();
}
private function init():void
{
if (stage) onInit();
else addEventListener(Event.ADDED_TO_STAGE, onInit);
}

private function onInit(event:Event = null):void
{
removeEventListener(Event.ADDED_TO_STAGE, onInit);
// entry point

addChild(new Canvas());
}

}

}

import flash.display.Bitmap;
import flash.display.BitmapData;
import flash.display.Shape;
import flash.display.Sprite;
import flash.events.TimerEvent;
import flash.utils.Timer;
/**
* …
* @author umhr
*/
class Canvas extends Sprite
{

private var sample:Bitmap = new Bitmap(new BitmapData(465, 465, false, 0xFFFFFFFF));
public function Canvas()
{
init();
}

private function init():void
{
addChild(sample);

check();
var timer:Timer = new Timer(1000);
timer.addEventListener(TimerEvent.TIMER, onTimer);
timer.start();
}

private function onTimer(event:TimerEvent):void
{
check();
}

private function check():void {
var i:int;
var r:int;
sample.bitmapData.fillRect(sample.bitmapData.rect, 0xFFFFFF);

var shape0:Shape = new Shape();
for (i = 0; i < 3; i++)
{
r = 100 * Math.random() + 50;
shape0.graphics.beginFill(0x000000);
shape0.graphics.drawCircle((465 – r * 2) * Math.random() + r, (465 – r * 2) * Math.random() + r, r);
shape0.graphics.endFill();
}

var date:Date = new Date();

var thete:Number = (date.getSeconds() / 60) * 2 * Math.PI;

shape0.graphics.beginFill(0xFF0000);
shape0.graphics.drawCircle(465*0.5+Math.sin(thete)*200, 465*0.5-Math.cos(thete)*200, 20);
shape0.graphics.endFill();

thete = (date.getMinutes() / 60) * 2 * Math.PI;
shape0.graphics.beginFill(0xFF0000);
shape0.graphics.drawCircle(465*0.5+Math.sin(thete)*150, 465*0.5-Math.cos(thete)*150, 30);
shape0.graphics.endFill();

thete = (date.getHours() / 12 + (date.getMinutes() /60)/12) * 2 * Math.PI;
shape0.graphics.beginFill(0xFF0000);
shape0.graphics.drawCircle(465*0.5+Math.sin(thete)*80, 465*0.5-Math.cos(thete)*80, 40);
shape0.graphics.endFill();

sample.bitmapData.draw(shape0);

var widthList:Array = [30, 20, 10];
var limitList:Array = [300, 750, 2000];
var nullCount:int;
var totalCount:int = 0;

var time:Number = new Date().time;

var n:int = widthList.length;
for (var j:int = 0; j < n; j++)
{
r = widthList[j];
nullCount = 0;

var imgCount:int = 0;
for (i = 0; i < 3000; i++)
{

var tx:Number = Math.random() * (sample.width – r*2) + r;
var ty:Number = Math.random() * (sample.height – r*2) + r;

if (checker(tx, ty, r)) {
var shape:Shape = new Shape();
shape.graphics.beginFill(0xFFFFFF, 1);
shape.graphics.drawCircle(tx, ty, r);
shape.graphics.endFill();
sample.bitmapData.draw(shape);
nullCount = 0;
imgCount ++;
}else {
nullCount ++;
if (nullCount > limitList[j]) {
break;
}
}

}
totalCount += imgCount;
}
}

private function checker(tx:Number, ty:Number, r:int):Boolean {

if(sample.bitmapData.getPixel(tx, ty) > 0){
return false;
}
var theta:Number
var n:int = 12;
for (var i:int = 0; i < n; i++)
{
theta = (i / n) * Math.PI * 2;
if(sample.bitmapData.getPixel(Math.cos(theta) * r + tx, Math.sin(theta) * r + ty) > 0){
return false;
}

}

return true;
}

}

[/sourcecode]