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var stop, staticx;
var img = new Image();
img.src = ".....png"
function Sakura(x, y, s, r, fn) {
this.x = x;
this.y = y;
this.s = s;
this.r = r;
this.fn = fn;
}
Sakura.prototype.draw = function (cxt) {
cxt.save();
var xc = 40 * this.s / 4;
cxt.translate(this.x, this.y);
cxt.rotate(this.r);
cxt.drawImage(img, 0, 0, 40 * this.s, 40 * this.s)
cxt.restore();
}
Sakura.prototype.update = function () {
this.x = this.fn.x(this.x, this.y);
this.y = this.fn.y(this.y, this.y);
this.r = this.fn.r(this.r);
if (this.x > window.innerWidth || this.x < 0 || this.y > window.innerHeight || this.y < 0) {
this.r = getRandom('fnr');
if (Math.random() > 0.4) {
this.x = getRandom('x');
this.y = 0;
this.s = getRandom('s');
this.r = getRandom('r');
} else {
this.x = window.innerWidth;
this.y = getRandom('y');
this.s = getRandom('s');
this.r = getRandom('r');
}
}
}
SakuraList = function () {
this.list = [];
}
SakuraList.prototype.push = function (sakura) {
this.list.push(sakura);
}
SakuraList.prototype.update = function () {
for (var i = 0, len = this.list.length; i < len; i++) {
this.list[i].update();
}
}
SakuraList.prototype.draw = function (cxt) {
for (var i = 0, len = this.list.length; i < len; i++) {
this.list[i].draw(cxt);
}
}
SakuraList.prototype.get = function (i) {
return this.list[i];
}
SakuraList.prototype.size = function () {
return this.list.length;
}
function getRandom(option) {
var ret, random;
switch (option) {
case 'x':
ret = Math.random() * window.innerWidth;
break;
case 'y':
ret = Math.random() * window.innerHeight;
break;
case 's':
ret = Math.random();
break;
case 'r':
ret = Math.random() * 6;
break;
case 'fnx':
random = -0.5 + Math.random() * 1;
ret = function (x, y) {
return x + 0.5 * random - 1.7;
};
break;
case 'fny':
random = 1.5 + Math.random() * 0.7
ret = function (x, y) {
return y + random;
};
break;
case 'fnr':
random = Math.random() * 0.03;
ret = function (r) {
return r + random;
};
break;
}
return ret;
}
function startSakura() {
requestAnimationFrame = window.requestAnimationFrame || window.mozRequestAnimationFrame || window.webkitRequestAnimationFrame || window.msRequestAnimationFrame || window.oRequestAnimationFrame;
var canvas = document.createElement('canvas'),
cxt;
staticx = true;
canvas.height = window.innerHeight;
canvas.width = window.innerWidth;
canvas.setAttribute('style', 'position: fixed;left: 0;top: 0;pointer-events: none;');
canvas.setAttribute('id', 'canvas_sakura');
document.getElementsByTagName('body')[0].appendChild(canvas);
cxt = canvas.getContext('2d');
var sakuraList = new SakuraList();
for (var i = 0; i < 50; i++) {
var sakura, randomX, randomY, randomS, randomR, randomFnx, randomFny;
randomX = getRandom('x');
randomY = getRandom('y');
randomR = getRandom('r');
randomS = getRandom('s');
randomFnx = getRandom('fnx');
randomFny = getRandom('fny');
randomFnR = getRandom('fnr');
sakura = new Sakura(randomX, randomY, randomS, randomR, {
x: randomFnx,
y: randomFny,
r: randomFnR
});
sakura.draw(cxt);
sakuraList.push(sakura);
}
stop = requestAnimationFrame(function () {
cxt.clearRect(0, 0, canvas.width, canvas.height);
sakuraList.update();
sakuraList.draw(cxt);
stop = requestAnimationFrame(arguments.callee);
})
}
img.onload = function () {
if(location.pathname === '/'){
startSakura();
}
}
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