forked from: setVector()検証 forked from: 重力マウス（100万パーティクル）

/**
 * Copyright hacker__a05fz1a ( http://wonderfl.net/user/hacker__a05fz1a )
 * MIT License ( http://www.opensource.org/licenses/mit-license.php )
 * Downloaded from: http://wonderfl.net/c/eGcf
 */

// forked from sekiryou's setVector()検証 forked from: 重力マウス（100万パーティクル）
// forked from clockmaker's 重力マウス（100万パーティクル）
// forked from cjcat2266's 重力マウス（プチ軽量化：25万パーティクル）
// forked from clockmaker's 重力マウス（プチ軽量化：10万パーティクル）
// forked from coppieee's 重力マウス（さらに軽量化してみた）
// forked from paq's forked from: 重力マウス（ちょっぴり軽量化してみた）
// forked from fumix's 重力マウス（リンクリストにしてみた）
// forked from undo's 重力マウス
//　リンクリストにしてみたけどそんなに速くない？？
//_bmd.fillRect()を_bmd.setPixel()に変更。
//sin(),cos(),atan2(),sqrt()を排除。
// Add final class / mouseEnalbled = false by clockmaker
// CJ Cat: Used vector instead of linked list.
// clockmaker: while文の処理を4回コピペしてイテレーションの回数を減らす 100万で30fps (FP10.1 Release))
// sekiryou: setVector()検証
package
{
	import flash.display.Bitmap;
	import flash.display.BitmapData;
	import flash.display.Sprite;
	import flash.display.StageAlign;
	import flash.display.StageScaleMode;
	import flash.events.Event;
	import flash.geom.ColorTransform;
	import flash.geom.Point;
	import flash.geom.Rectangle;
	import flash.utils.ByteArray;
	import net.hires.debug.Stats;

	[SWF(frameRate='48', width='465', height='465', backgroundColor='0x0')]

	public class Main extends Sprite {
		private var _bmp:Bitmap;
		private var _bmd:BitmapData;
		private var _bmdRect:Rectangle;
		private var _colorTransform:ColorTransform = new ColorTransform(0.97, 0.9, 0.9, 1.0);

		private const _maxNum:int = 1000000;
		private var _cnt:int = 0;
		
		private const _particleData:Vector.<Number> = new Vector.<Number>(_maxNum * 4, true);
		

		public function Main() {
			if(stage) init(null);
			else addEventListener(Event.ADDED_TO_STAGE, init);
		}
				
		private function init(evt:Event):void {
			removeEventListener(Event.ADDED_TO_STAGE, init);
			
			this.stage.align = StageAlign.TOP_LEFT;
			this.stage.scaleMode = StageScaleMode.NO_SCALE;
			this.stage.quality = "low";
			this.mouseEnabled = false;
			this.mouseChildren = false;
		
			_bmd = new BitmapData(465, 465, false, 0x000000);
			_bmp = new Bitmap(_bmd);
			addChild(_bmp);
			this._bmdRect = _bmd.rect;
			
			var i0:int, i1:int, i2:int, i3:int;
			i0 = 0;
			while (i0 < _maxNum) {
				i1 = i0;
				i2 = ++i1;
				i3 = ++i2;
				i3++;
				
				_particleData[i0] = Math.random() * 465 >> 0;
				_particleData[i1] = Math.random() * 465 >> 0;
				_particleData[i2] = 0;
				_particleData[i3] = 0;
				
				i0 = ++i3;
			}
			
			addChild(new Stats());
			addEventListener(Event.ENTER_FRAME, onEnter);
		}

		private function onEnter(evt:Event):void {
			var pv:Vector.<uint> = this._bmd.getVector(this._bmdRect);
			var gravPoint_x:Number = mouseX;
			var gravPoint_y:Number = mouseY;
			var calc:Boolean = _cnt % 6 == 0;
			
			//this._bmd.lock();
			
			var diff_x:Number, diff_y:Number, acc:Number;//, acc_x:Number, acc_y:Number;
			var i0:int, i1:int, i2:int, i3:int, j0:int, j1:int, j2:int, j3:int, k0:int, k1:int, k2:int, k3:int, l0:int, l1:int, l2:int, l3:int;
			i0 = 0;
			while (i0 < _maxNum)
			{
				i1 = i0;
				i2 = ++i1;
				i3 = ++i2;
				j0 = ++i3;
				j1 = ++j0;
				j2 = ++j1;
				j3 = ++j2;
				k0 = ++j3;
				k1 = ++k0;
				k2 = ++k1;
				k3 = ++k2;
				l0 = ++k3;
				l1 = ++l0;
				l2 = ++l1;
				l3 = ++l2;
				l3++;
				
						
				if(calc){
					diff_x = gravPoint_x - _particleData[i0];
					diff_y = gravPoint_y - _particleData[i1];
					acc = 400 / (diff_x * diff_x + diff_y * diff_y);
					//acc_x = acc * diff_x;
					//acc_y = acc * diff_y;
					_particleData[i2] += acc * diff_x;
					_particleData[i3] += acc * diff_y;
					
					diff_x = gravPoint_x - _particleData[j0];;
					diff_y = gravPoint_y - _particleData[j1];
					acc = 400 / (diff_x * diff_x + diff_y * diff_y);
					//acc_x = acc * diff_x;
					//acc_y = acc * diff_y;
					_particleData[j2] += acc * diff_x;
					_particleData[j3] += acc * diff_y;
					
					diff_x = gravPoint_x - _particleData[k0];;
					diff_y = gravPoint_y - _particleData[k1];
					acc = 400 / (diff_x * diff_x + diff_y * diff_y);
					//acc_x = acc * diff_x;
					//acc_y = acc * diff_y;
					_particleData[k2] += acc * diff_x;
					_particleData[k3] += acc * diff_y;
					diff_x = gravPoint_x - _particleData[l0];;
					diff_y = gravPoint_y - _particleData[l1];
					acc = 400 / (diff_x * diff_x + diff_y * diff_y);
					//acc_x = acc * diff_x;
					//acc_y = acc * diff_y;
					_particleData[l2] += acc * diff_x;
					_particleData[l3] += acc * diff_y;
				}
				
				_particleData[i0] += _particleData[i2];
				_particleData[i1] += _particleData[i3];
				_particleData[i2] *= 0.96;
				_particleData[i3] *= 0.96;
				if (_particleData[i0] < 465 && _particleData[i1] < 465 && _particleData[i0] > 0 && _particleData[i1] > 0)
				pv[int(_particleData[i0] + int(_particleData[i1]) * 465)] = 0xffffff;
				
				_particleData[j0] += _particleData[j2];
				_particleData[j1] += _particleData[j3];
				_particleData[j2] *= 0.96;
				_particleData[j3] *= 0.96;
				if (_particleData[j0] < 465 && _particleData[j1] < 465 && _particleData[j0] > 0 && _particleData[j1] > 0)
				pv[int(_particleData[j0] + int(_particleData[j1]) * 465)] = 0xffffff;
				
				_particleData[k0] += _particleData[k2];
				_particleData[k1] += _particleData[k3];
				_particleData[k2] *= 0.96;
				_particleData[k3] *= 0.96;
				if (_particleData[k0] < 465 && _particleData[k1] < 465 && _particleData[k0] > 0 && _particleData[k1] > 0)
				pv[int(_particleData[k0] + int(_particleData[k1]) * 465)] = 0xffffff;
				
				_particleData[l0] += _particleData[l2];
				_particleData[l1] += _particleData[l3];
				_particleData[l2] *= 0.96;
				_particleData[l3] *= 0.96;
				if (_particleData[l0] < 465 && _particleData[l1] < 465 && _particleData[l0] > 0 && _particleData[l1] > 0)
				pv[int(_particleData[l0] + int(_particleData[l1]) * 465)] = 0xffffff;
				
				i0 = ++l3;
			}
			this._bmd.setVector(this._bmdRect, pv);
			this._bmd.colorTransform(this._bmdRect, this._colorTransform);
			//this._bmd.unlock();
			
			//_cnt++;
			_cnt += 1;
		}
	}
}