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Dead Code Preservation :: Archived AS3 works from wonderfl.net

forked from: Flight404 Particles (trails)

yd_niku さんの
Flight404 の人のコードをAS3にしてみた ver2
http://wonderfl.kayac.com/code/881224c6000816b64f79b854671a48eeeac7c8d0
をもとに Flash でもそれなりの速度が出るよう書き直した
画像をプリレンダリングしたり
Particle オブジェクトを使い回したり
機を見て BitmapData.draw でなく BitmapData.copyPixels を使ったり等している
trails の描画を少しいい加減にした
他、trails の on/off (T key)、フルクリーンモード等
/**
 * Copyright alpicola ( http://wonderfl.net/user/alpicola )
 * MIT License ( http://www.opensource.org/licenses/mit-license.php )
 * Downloaded from: http://wonderfl.net/c/i5Kn
 */

// forked from 5ivestar's Flight404 Particles (trails)
// forked from 5ivestar's Flight404 Particles
// yd_niku さんの
// Flight404 の人のコードをAS3にしてみた ver2
// http://wonderfl.kayac.com/code/881224c6000816b64f79b854671a48eeeac7c8d0
// をもとに Flash でもそれなりの速度が出るよう書き直した

// 画像をプリレンダリングしたり
// Particle オブジェクトを使い回したり
// 機を見て BitmapData.draw でなく BitmapData.copyPixels を使ったり等している

// trails の描画を少しいい加減にした
// 他、trails の on/off (T key)、フルクリーンモード等

package {
	import flash.display.*;
	import flash.events.*;
	import flash.geom.*;
	import flash.text.*;
	import flash.ui.*;
	//import com.flashdynamix.utils.SWFProfiler;

	 [SWF(backgroundColor="#000000", frameRate="40")]

	public class Particles extends Sprite {

		private var canvas:BitmapData;
		private var bitmap:Bitmap;
		private var emitter:Emitter;
		private var mousePressed:Boolean;
		private var stats:TextField;

		public function Particles() {
			//SWFProfiler.init(stage, this);
			//stage.quality = "low";
			stage.scaleMode = "noScale";
			stage.align = "TL";
			//Mouse.hide();

			canvas = new BitmapData(stage.stageWidth, stage.stageHeight, false, 0x000000);
			bitmap = new Bitmap(canvas)
			addChild(bitmap);
			emitter = new Emitter();

			/*stats = new TextField();
			stats.x = 5;
			stats.y = 5;
			stats.autoSize = "left";
			stats.textColor = 0xFFFFFF;
			addChild(stats);*/

			addEventListener(Event.ENTER_FRAME, render);
			stage.addEventListener(MouseEvent.MOUSE_DOWN, function(e:MouseEvent):void {
				mousePressed = true;
			});
			stage.addEventListener(MouseEvent.MOUSE_UP, function(e:MouseEvent):void {
				mousePressed = false;
			});
			stage.addEventListener(KeyboardEvent.KEY_DOWN, function(e:KeyboardEvent):void {
				var key:String = String.fromCharCode(e.charCode);
				if (key == 't' || key == 'T') emitter.allowTrails = !emitter.allowTrails;
			});
			stage.addEventListener(FullScreenEvent.FULL_SCREEN, function(e:FullScreenEvent):void {
				canvas = new BitmapData(stage.stageWidth, stage.stageHeight, false, 0x000000);
				bitmap.bitmapData = canvas;
			});

			var menu:ContextMenu = new ContextMenu();
			var item:ContextMenuItem = new ContextMenuItem("Full Screen");
			contextMenu = menu;
			menu.hideBuiltInItems();
			menu.customItems.push(item);
			menu.addEventListener(ContextMenuEvent.MENU_SELECT, function(e:ContextMenuEvent):void {
				switch (stage.displayState) {
					case "normal":     item.enabled = true;  break;
					case "fullScreen": item.enabled = false; break;
				}
			});
			item.addEventListener(ContextMenuEvent.MENU_ITEM_SELECT, function(e:ContextMenuEvent):void {
				stage.displayState = "fullScreen";
			});
		}

		public function render(e:Event):void {
			emitter.moveTo(mouseX, mouseY);
			if (mousePressed) emitter.emitParticles(5);
			canvas.lock();
			canvas.fillRect(canvas.rect, 0x000000);
			emitter.render(canvas);
			canvas.unlock();
		}

	}
}

import flash.display.*;
import flash.geom.*;

class Emitter {

	private var position:Vector3D = new Vector3D();
	private var velocity:Vector3D = new Vector3D();
	private var particles:Vector.<Particle> = new Vector.<Particle>(500, true);
	private var candicates:uint = 0;
	private var lineBuffer:Shape = new Shape();
	public  var allowTrails:Boolean = true;

	public function Emitter() {
		var n:int = particles.length;
		while (n--) particles[n] = new Particle();
	}

	public function moveTo(x:Number, y:Number):void {
		velocity.x = (x - position.x) * 0.35;
		velocity.y = (y - position.y) * 0.35;
		position.incrementBy(velocity);
	}

	public function render(canvas:BitmapData):void {
		var n:int, m:int = 0;
		n = particles.length;
		var particle:Particle;
		var g:Graphics = lineBuffer.graphics;
		while (n--) {
			particle = particles[n];
			if (particle.alive) {
				particle.render(canvas);
				if (allowTrails) {
					particle.renderTails(lineBuffer);
					if ((++m & 31) == 0) {
						canvas.draw(lineBuffer, null, null, "add");
						g.clear();
					}
				}
			} else if (candicates) {
				candicates--;
				var p:Vector3D, v:Vector3D;
				p = position.clone();
				p.x += (Math.random() - 0.5) * 5;
				p.y += (Math.random() - 0.5) * 5;
				p.z += (Math.random() - 0.5) * 5;
				v = velocity.clone();
				v.x += (Math.random() - 0.5) * 10;
				v.y += (Math.random() - 0.5) * 10;
				v.z += (Math.random() - 0.5) * 10;
				particle.init(p, v);
				particle.render(canvas);
			}
		}
		if (allowTrails) {
			canvas.draw(lineBuffer, null, null, "add");
			g.clear();
		}
	}

	public function emitParticles(n:uint):void {
		candicates += n;
	}

}

class Particle {

	//static private const FLOOR_LEVEL:uint = 360;
	static private const Z_FAR:uint = 1000;
	static private const IMAGES:Vector.<BitmapData> = loadImages();

	private var position:Vector3D;
	private var velocity:Vector3D;
	private var trail:Vector.<Vector3D> = new Vector.<Vector3D>();
	private var lifeSpan:uint;
	private var age:uint;
	private var bounce:uint;
	private var images:Vector.<BitmapData>;
	private var matrix:Matrix = new Matrix();
	private var transform:ColorTransform = new ColorTransform();
	private var point:Point = new Point();
	private var rectangle:Rectangle = new Rectangle();
	private var yAxis:Vector3D;
	public  var alive:Boolean = false;

	static private function loadImages():Vector.<BitmapData> {
		var s:Shape = new Shape();
		var matrix:Matrix = new Matrix();
		matrix.createGradientBox(32, 32);
		s.graphics.beginGradientFill(GradientType.RADIAL, [0xFFFFFF, 0xFF0000, 0xFF0000], [1, 0.2, 0], [0, 88, 255], matrix);
		s.graphics.drawCircle(16, 16, 16);
		s.graphics.endFill();
		var images:Vector.<BitmapData> = new Vector.<BitmapData>(64 * 32, true);
		var transform:ColorTransform = new ColorTransform();
		for (var i:int = 0; i < 64; i++) {
			for (var j:int = 1; j < 32; j++) {
				var image:BitmapData = new BitmapData(j, j, true, 0x000000);
				matrix.identity();
				matrix.scale(j/32, j/32);
				transform.blueOffset = i * 4;
				image.draw(s, matrix, transform);
				images[int(i*32+j)] = image;
			}
		}
		return images;
	}

	public function Particle() {
		images = IMAGES;
		yAxis  = Vector3D.Y_AXIS;
	}

	public function init(p:Vector3D, v:Vector3D):void {
		position = p;
		velocity = v;
		lifeSpan = (Math.random() + 0.5) * 60;
		age    = 0;
		bounce = 0;
		alive  = true;
		trail.splice(0, trail.length);
	}

	public function render(canvas:BitmapData):void {
		var d:Number = position.x + position.y + position.z;
		velocity.x += Math.cos(d) * 0.5;
		velocity.y += Math.sin(d) * 0.5 + 0.35;
		velocity.z += Math.cos(d) * -0.5;
		if (position.y > canvas.height * 0.6) {
			velocity.scaleBy(0.75);
			velocity.y *= -0.5;
			bounce++;
			age += bounce * 3;
		} else {
			age++;
		}
		position.incrementBy(velocity);

		if (age < lifeSpan) {
			var perspective:Number = Z_FAR / (Z_FAR - position.z);
			var diameter:uint = (lifeSpan - age) * perspective * 0.5;
			var color:uint = 32 * age / lifeSpan;
			if (diameter <= 0 || 32 <= diameter) return;
			if (age < 20) {
				matrix.tx = position.x * perspective - diameter * 0.5;
				matrix.ty = position.y * perspective - diameter * 0.5;
				canvas.draw(images[int(color * 32 + diameter)], matrix, null, "add");
			} else {
				point.x = position.x * perspective - diameter * 0.5;
				point.y = position.y * perspective - diameter * 0.5;
				rectangle.width = rectangle.height = diameter;
				canvas.copyPixels(images[int(color * 32 + diameter)], rectangle, point, null, null, true);
			}
		} else {
			alive = false;
		}
	}

	public function renderTails(buffer:Shape):void {
		var length:int = trail.length;
		var p:Vector3D = velocity.crossProduct(yAxis);
		p.normalize();
		if ((age & 1) == 0 || length == 0) {
			trail[int(length)]   = position.clone();
			trail[int(length+1)] = p;
		} else {
			trail[int(length-2)] = position.clone();
			trail[int(length-1)] = p;
		}

		var g:Graphics = buffer.graphics;
		var v:Vector3D, p1:Vector3D, p2:Vector3D, p3:Vector3D, p4:Vector3D;
		var f1:Number, f2:Number, f3:Number, f4:Number;
		p1 = p2 = trail[0];
		f1 = f2 = Z_FAR / (Z_FAR - p1.z);
		length = length >> 1;
		for (var i:int = 1; i < length; i++) {
			var per:Number = i / length;
			v = trail[int(i*2+1)].clone();
			v.scaleBy(per * (lifeSpan - age) * 0.02)
			p3 = trail[int(i*2)].add(v);
			v.negate();
			p4 = trail[int(i*2)].add(v);
			f3 = Z_FAR / (Z_FAR - p3.z);
			f4 = Z_FAR / (Z_FAR - p4.z);
			g.beginFill((per * 0xFF) << 16 | (per * 0.5 * 0xFF) << 8 | (1.5 - per) * 0xFF, per);
			g.moveTo(p1.x * f1, p1.y * f1);
			g.lineTo(p2.x * f2, p2.y * f2);
			g.lineTo(p4.x * f4, p4.y * f4);
			g.lineTo(p3.x * f3, p3.y * f3);
			g.endFill();
			f1 = f3;
			f2 = f4;
			p1 = p3;
			p2 = p4;
		}

		if (length > 5) {
			trail.slice(0, 2);
		}
	}

}