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var __extends = (this && this.__extends) || (function () {
var extendStatics = Object.setPrototypeOf ||
({ __proto__: [] } instanceof Array && function (d, b) { d.__proto__ = b; }) ||
function (d, b) { for (var p in b) if (b.hasOwnProperty(p)) d[p] = b[p]; };
return function (d, b) {
extendStatics(d, b);
function __() { this.constructor = d; }
d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
};
})();
window.addEventListener('DOMContentLoaded', init);
//#region classes
var Vector = /** @class */ (function () {
function Vector() {
this.x = 0;
this.y = 0;
this.vx = 0;
this.vy = 0;
this.angle = 0;
this.va = 0.05;
}
return Vector;
}());
var Particle = /** @class */ (function (_super) {
__extends(Particle, _super);
function Particle() {
var _this = _super !== null && _super.apply(this, arguments) || this;
_this.id = Math.random().toString();
_this.color = randomColor();
_this.radius = 8;
_this.opacity = 1;
return _this;
}
return Particle;
}(Vector));
var Unicorn = /** @class */ (function (_super) {
__extends(Unicorn, _super);
function Unicorn(image) {
var _this = _super.call(this) || this;
_this.image = image;
return _this;
}
return Unicorn;
}(Vector));
var Tile = /** @class */ (function (_super) {
__extends(Tile, _super);
function Tile() {
var _this = _super !== null && _super.apply(this, arguments) || this;
_this.color = randomColor();
_this.width = 30;
_this.height = 10;
_this.opacity = 1;
return _this;
}
return Tile;
}(Vector));
var ParticleFactory = /** @class */ (function () {
function ParticleFactory() {
}
ParticleFactory.archive = function (p) {
ParticleFactory.particleArchive[p.id] = Object.assign({}, p);
};
ParticleFactory.retrieve = function (p) {
if (p.id in ParticleFactory.particleArchive) {
return ParticleFactory.particleArchive[p.id];
}
return null;
};
ParticleFactory.create = function (options) {
var p = new Particle();
Object.assign(p, options);
ParticleFactory.archive(p);
return p;
};
ParticleFactory.reset = function (p) {
var archivedVersion = ParticleFactory.retrieve(p);
if (archivedVersion) {
;
Object.assign(p, archivedVersion);
}
};
ParticleFactory.particleArchive = {};
return ParticleFactory;
}());
var Renderer = /** @class */ (function () {
function Renderer($) {
var _this = this;
this.$ = $;
this.renderParticle = function (p) {
var $ = _this.$;
var x = p.x, y = p.y, radius = p.radius, color = p.color, opacity = p.opacity;
$.save();
$.globalAlpha = opacity;
$.fillStyle = color;
$.translate(x, y);
$.beginPath();
$.arc(0, 0, radius, 0, PI2);
$.fill();
$.stroke();
$.restore();
};
this.renderStar = function (p) {
var $ = _this.$;
var radius = p.radius, color = p.color, x = p.x, y = p.y, opacity = p.opacity;
$.save();
$.translate(x, y);
$.fillStyle = color;
$.globalAlpha = opacity;
$.beginPath();
for (var i = 5; i--;) {
$.lineTo(0, radius);
$.translate(0, radius);
$.rotate(PI2 / 10);
$.lineTo(0, -radius);
$.translate(0, -radius);
$.rotate(-((Math.PI * 6) / 10));
}
$.lineTo(0, radius);
$.fill();
$.stroke();
$.restore();
};
this.renderTile = function (t) {
var $ = _this.$;
var x = t.x, y = t.y, width = t.width, height = t.height, color = t.color, opacity = t.opacity;
$.save();
$.globalAlpha = opacity;
$.fillStyle = color;
$.translate(x, y);
$.beginPath();
$.rect(0, 0, width, height);
$.fill();
$.stroke();
$.restore();
};
}
Renderer.prototype.clearScreen = function () {
var $ = this.$;
$.clearRect(0, 0, $.canvas.width, $.canvas.height);
};
Renderer.prototype.renderImage = function (img, x, y) {
var $ = this.$;
$.save();
$.drawImage(img, x, y);
$.restore();
};
Renderer.prototype.renderUnicorn = function (u) {
this.renderImage(u.image, u.x, u.y);
};
return Renderer;
}());
//#endregion
//#region globals
var CANVAS = document.createElement('canvas');
var CTX = CANVAS.getContext('2d');
var WIDTH = (CANVAS.width = window.innerWidth);
var HEIGHT = (CANVAS.height = window.innerHeight);
var PI2 = 2 * Math.PI;
var GRAVITY = 0.125;
var COLOR_FADE = 0.01;
var COLORS = [
'#9400D3',
'#4B0082',
'#0000FF',
'#00FF00',
'#FFFF00',
'#FF7F00',
'#FF0000'
];
var RENDERER = new Renderer(CTX);
var TILES = [];
var PARTICLES = [];
var PARTICLE_COUNT = 40;
var UNICORN_IMAGE = document.getElementById('unicorn');
var UNICORN = new Unicorn(UNICORN_IMAGE);
//#endregion
//#region utils
function randomColor() {
return sample(COLORS);
}
function randomNumber(min, max) {
return Math.random() * (max - min) + min;
}
function randomBoolean() {
return Math.random() > 0.5;
}
function sample(a) {
return a[Math.floor(Math.random() * a.length)];
}
function outsideScreen(p) {
var diameter = p.radius * 2;
var yExceeded = p.y - diameter > HEIGHT || p.y + diameter < 0;
var xExceeded = p.x - diameter > WIDTH || p.x + diameter < 0;
return yExceeded || xExceeded;
}
//#endregion
//#region animation
function updateParticle(p) {
p.vy += GRAVITY;
p.y += p.vy;
p.x += p.vx;
if (p.opacity > COLOR_FADE) {
p.opacity -= COLOR_FADE;
}
if (outsideScreen(p)) {
ParticleFactory.reset(p);
}
}
function updateUnicorn(unicorn) {
var image = unicorn.image;
var centerX = WIDTH / 2 - image.width / 2;
var centerY = HEIGHT / 2 - image.height / 2 - 50;
var radiusX = 20;
var radiusY = 8;
unicorn.x = centerX + Math.cos(unicorn.angle) * radiusX;
unicorn.y = centerY + Math.sin(unicorn.angle) * radiusY;
unicorn.angle += unicorn.va;
}
function animation() {
requestAnimationFrame(animation);
RENDERER.clearScreen();
TILES.forEach(updateTile);
TILES.forEach(RENDERER.renderTile);
PARTICLES.forEach(updateParticle);
PARTICLES.forEach(RENDERER.renderStar);
if (UNICORN_IMAGE.complete) {
updateUnicorn(UNICORN);
RENDERER.renderUnicorn(UNICORN);
}
}
function createParticles() {
for (var i = PARTICLE_COUNT; i > 0; --i) {
var p = ParticleFactory.create({
x: WIDTH / 2,
y: HEIGHT / 2,
vx: randomNumber(-14, -3),
vy: randomNumber(-8, 2)
});
var i_1 = Math.floor(randomNumber(0, 60)) + 1;
while (i_1--) {
updateParticle(p);
}
PARTICLES.push(p);
}
}
function updateTile(t) {
t.vx -= GRAVITY;
t.x += t.vx;
t.y += t.vy;
if (t.x + t.width < 0) {
t.x = randomNumber(0, WIDTH) + WIDTH;
t.vx = 0;
}
}
function createTiles() {
var tileCount = HEIGHT / 10;
for (var i = tileCount; i > 0; --i) {
var tileWidth = randomNumber(60, 120);
var t = new Tile();
t.opacity = randomNumber(0.1, 0.6);
t.width = tileWidth;
t.x = tileWidth * (i - 1);
t.y = t.height * (i - 1);
var ii = Math.floor(randomNumber(0, 260)) + 1;
while (ii--) {
updateTile(t);
}
TILES.push(t);
}
}
function setup() {
document.body.appendChild(CANVAS);
var unicornX = WIDTH / 2 - UNICORN.image.width / 2;
var unicornY = HEIGHT / 2 - UNICORN.image.height / 2;
UNICORN.x = unicornX;
UNICORN.y = unicornY;
createTiles();
createParticles();
}
function init() {
setup();
animation();
}
//#endregion
