forked from: RainyDay
blog@http://tirirenge.undo.jp/?p=1821
/**
* Copyright Saqoosha ( http://wonderfl.net/user/Saqoosha )
* MIT License ( http://www.opensource.org/licenses/mit-license.php )
* Downloaded from: http://wonderfl.net/c/25ff
*/
// forked from ahchang's RainyDay
// forked from Saqoosha's forked from: Snow
// forked from Saqoosha's Snow
/*
* blog@http://tirirenge.undo.jp/?p=1821
*/
package {
import flash.display.Bitmap;
import flash.display.BitmapData;
import flash.display.BlendMode;
import flash.display.PixelSnapping;
import flash.display.Sprite;
import flash.events.Event;
import flash.filters.BlurFilter;
import flash.filters.ColorMatrixFilter;
import flash.geom.Matrix;
import flash.geom.Point;
import flash.text.TextField;
import flash.text.TextFieldAutoSize;
import flash.text.TextFormat;
import flash.utils.Dictionary;
import net.hires.debug.Stats;
import frocessing.color.ColorHSV;
[SWF(width=465, height=465, backgroundColor=0x0, frameRate=120)]
public class RainyDay extends Sprite {
private static const GRAVITY:Number = 20;
private static const DRAG:Number = 0.7;
private static const ZERO_POINT:Point = new Point(0, 0);
private var _canvas:BitmapData;
private var _glow:BitmapData;
private var _glowMtx:Matrix;
private var _forceMap:BitmapData;
// private var _snow:Array;
private var _snow:Dictionary;
private var _color:ColorMatrixFilter = new ColorMatrixFilter([
1, 0, 0, 0, -5,
0, 1, 0, 0, -5,
0, 0, 1, 0, -5,
0, 0, 0, 1, 0
]);
private var _hsv:ColorHSV = new ColorHSV();
private var _blur:BlurFilter = new BlurFilter(1.5, 1.5, 1);
public function RainyDay() {
this._canvas = new BitmapData(465, 465, false, 0x0); // カンバスをつくる。ここに 1 pixel ずつ描いていくよ
this.addChild(new Bitmap(this._canvas)) as Bitmap; // stage に配置
/*this._glow = new BitmapData(465 / 4, 465 / 4, false, 0x0); // キラキラを描く用のん。カンバスの 4 分の 1 のサイズ
var bm:Bitmap = this.addChild(new Bitmap(this._glow, PixelSnapping.NEVER, true)) as Bitmap; // smoothing を true にして配置
//bm.scaleX = bm.scaleY = 4; // 4 倍にする。
bm.blendMode = BlendMode.ADD; // 加算モードで合成
this._glowMtx = new Matrix(0.25, 0, 0, 0.25);*/
// 雪を積もらせるかたちを BitmapData に描く。
var tf:TextField = new TextField();
tf.defaultTextFormat = new TextFormat('Verdana', 64, 0xffffff, true);
tf.autoSize = TextFieldAutoSize.LEFT;
tf.text = 'Rainyday';
tf.x = (465 - tf.width) / 2;
tf.y = (465 - tf.height) / 2;
this._forceMap = new BitmapData(465, 465, false, 0x0);
this._forceMap.draw(tf, tf.transform.matrix);
this._forceMap.applyFilter(this._forceMap, this._forceMap.rect, new Point(0, 0), new BlurFilter(8, 8));
// this._snow = []; // 雪パーティクルはここにいれておくよ。
this._snow = new Dictionary();
this.addChild(new Stats());
this.addEventListener(Event.ENTER_FRAME, this.update); // 毎フレーム update を呼ぶよ
}
// 雪を 1 粒発生させる関数
public function emitParticle(ex:Number, ey:Number, s:Number = 1, c:int = 0x00bfff, vx:Number = 0, vy:Number = 0):void {
var p:SnowParticle = new SnowParticle(); // 作って
// パラメータ設定して
p.x = ex;
p.y = ey;
p.vx = vx;
p.vy = vy;
p.s = s;
p.c = c;
// this._snow.push(p); // 保存
this._snow[p] = true;
}
// 雪を動かすよーー
public function update(e:Event):void {
this._canvas.lock(); // いっぱい setPixel するときは必ず lock しよう
this._canvas.applyFilter(this._canvas, this._canvas.rect, ZERO_POINT, this._color);
this._canvas.applyFilter(this._canvas, this._canvas.rect, ZERO_POINT, this._blur);
// this._canvas.fillRect(this._canvas.rect, 0x0); // カンバスをクリア
// var n:int = this._snow.length;
var d:Number;
var gravity:Number = GRAVITY / 100; // あらかじめ計算しとく
// while (n--) {
for (var key:* in this._snow) {
var p:SnowParticle = SnowParticle(key);
// var p:SnowParticle = this._snow[n];
// p.vx += 0.02;
p.vy += gravity * p.s; // まず重力を加える
p.vx *= 0.99; // 空気抵抗
p.vy *= 0.99; // y 方向にも
d = 1 - (this._forceMap.getPixel(p.x, p.y) / 0xffffff) * DRAG; // forceMap にもとづいて抵抗値を計算。黒→速い、白→遅い。
p.vx *= d; // forceMap から得た抵抗値を適用
p.vy *= d; // y 方向にも
var px:int = p.x;
var py:int = p.y;
p.x += p.vx; // 動かす
p.y += p.vy;
// this._canvas.setPixel(p.x, p.y, p.c); // 雪 1 粒描く
_drawLine(p.x, p.y, px, py, p.c, 1);
if (p.y > this.stage.stageHeight) { // もし画面外にでちゃったら
// this._snow.splice(n, 1); // とりのぞく
delete this._snow[p];
}
}
this._canvas.unlock(); // lock したやつは必ず unlock
//this._glow.draw(this._canvas, this._glowMtx); // キラキラを描く
// 雪を発生させますよ
// var n = 10;
// while (n--) {
for (var i:int = 0; i < 8; i++) {
_hsv.h = Math.random() * 20 + 180;
this.emitParticle(Math.random() * this.stage.stageWidth, -20, Math.random() + 0.5, _hsv.value);
}
}
private function _drawLine(x0:int, y0:int, x1:int, y1:int, color:int, alpha:Number):void {
var steep:Boolean = Math.abs(y1 - y0) > Math.abs(x1 - x0);
var tmp:int;
if (steep) {
tmp = x0;
x0 = y0;
y0 = tmp;
tmp = x1;
x1 = y1;
y1 = tmp;
}
if (x0 > x1) {
tmp = x0;
x0 = x1;
x1 = tmp;
tmp = y0;
y0 = y1;
y1 = tmp;
}
var deltax:int = x1 - x0;
var deltay:int = Math.abs(y1 - y0);
var error:int = deltax / 2;
var ystep:int;
var y:int = y0;
if (y0 < y1) {
ystep = 1;
} else {
ystep = -1;
}
for (var x:int = x0; x <= x1; x++) {
if (steep) {
this._canvas.setPixel32(y, x, color | ((alpha * 0xff) << 24));
} else {
this._canvas.setPixel32(x, y, color | ((alpha * 0xff) << 24));
}
error = error - deltay;
if (error < 0) {
y = y + ystep;
error = error + deltax;
}
}
}
}
}
class SnowParticle {
public var x:Number;
public var y:Number;
public var vx:Number;
public var vy:Number;
public var s:Number;
public var c:int;
public function SnowParticle() {
this.x = 0;
this.y = 0;
this.vx = 0;
this.vy = 0;
this.s = 1;
this.c = 0xffffff;
}
}