lava-lamp-bubbles
Version:
Lava lamp bubbles on canvas
254 lines (253 loc) • 9.23 kB
JavaScript
"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
var LavaLampBubbles = /** @class */ (function () {
function LavaLampBubbles(canvasID, speed, color1, color2) {
var _this = this;
// canvas
this.screen = new Ge1doot(canvasID).init(true);
this.ctx = this.screen.ctx;
this.screen.resize();
window.addEventListener("resize", function () { return _this.screen.resize(); });
// create LavaLamps
this.lava0 = new LavaLamp(this.ctx, this.screen.width, this.screen.height, speed, 10, color1, color2);
}
LavaLampBubbles.prototype.start = function () {
var _this = this;
requestAnimationFrame(function () { return _this.start(); });
this.ctx.clearRect(0, 0, screen.width, screen.height);
this.lava0.renderMetaballs();
};
return LavaLampBubbles;
}());
exports.default = LavaLampBubbles;
var Ge1doot = /** @class */ (function () {
function Ge1doot(id) {
this.width = 0;
this.height = 0;
this.left = 0;
this.top = 0;
this.elem = document.getElementById(id);
if (this.elem === null)
throw "Invalid Canvas id!";
this.ctx = this.elem.getContext("2d");
}
Ge1doot.prototype.init = function (initRes) {
var _this = this;
window.addEventListener("resize", function () { return _this.resize(); });
this.elem.onselectstart = function () {
return false;
};
this.elem.ondrag = function () {
return false;
};
initRes && this.resize();
return this;
};
Ge1doot.prototype.resize = function () {
var o = this.elem;
this.width = o.offsetWidth;
this.height = o.offsetHeight;
for (this.left = 0, this.top = 0; o != null; o = o.offsetParent) {
this.left += o.offsetLeft;
this.top += o.offsetTop;
}
if (this.ctx) {
this.elem.width = this.width;
this.elem.height = this.height;
}
};
return Ge1doot;
}());
var Point = /** @class */ (function () {
function Point(x, y) {
this.computed = 0;
this.force = 0;
this.x = x;
this.y = y;
this.magnitude = x * x + y * y;
this.computed = 0;
this.force = 0;
}
Point.prototype.add = function (p) {
return new Point(this.x + p.x, this.y + p.y);
};
return Point;
}());
var Ball = /** @class */ (function () {
function Ball(par) {
var min = 0.05;
var max = 0.075;
this.vel = new Point((Math.random() > 0.5 ? 1 : -1) * (0.2 + Math.random() * 0.25) * 0.25 * par.speed, (Math.random() > 0.5 ? 1 : -1) * (0.2 + Math.random()) * 0.25 * par.speed);
this.pos = new Point(par.width * 0.2 + Math.random() * par.width * 0.6, par.height * 0.2 + Math.random() * par.height * 0.6);
this.size = par.wh / 15 + (Math.random() * (max - min) + min) * (par.wh / 15);
this.width = par.width;
this.height = par.height;
}
Ball.prototype.move = function () {
// bounce borders
if (this.pos.x >= this.width - this.size) {
if (this.vel.x > 0)
this.vel.x = -this.vel.x;
this.pos.x = this.width - this.size;
}
else if (this.pos.x <= this.size) {
if (this.vel.x < 0)
this.vel.x = -this.vel.x;
this.pos.x = this.size;
}
if (this.pos.y >= this.height - this.size) {
if (this.vel.y > 0)
this.vel.y = -this.vel.y;
this.pos.y = this.height - this.size;
}
else if (this.pos.y <= this.size) {
if (this.vel.y < 0)
this.vel.y = -this.vel.y;
this.pos.y = this.size;
}
// velocity
this.pos = this.pos.add(this.vel);
};
return Ball;
}());
var LavaLamp = /** @class */ (function () {
function LavaLamp(ctx, width, height, speed, numBalls, c0, c1) {
this.step = 5;
this.paint = false;
this.iter = 0;
this.sign = 1;
this.ctx = ctx;
this.step = 5;
this.width = width;
this.height = height;
this.wh = Math.min(width, height);
this.sx = Math.floor(this.width / this.step);
this.sy = Math.floor(this.height / this.step);
this.speed = speed;
this.paint = false;
this.metaFill = createRadialGradient(this.ctx, width, height, width, c0, c1);
this.plx = [0, 0, 1, 0, 1, 1, 1, 1, 1, 1, 0, 1, 0, 0, 0, 0];
this.ply = [0, 0, 0, 0, 0, 0, 1, 0, 0, 1, 1, 1, 0, 1, 0, 1];
this.mscases = [0, 3, 0, 3, 1, 3, 0, 3, 2, 2, 0, 2, 1, 1, 0];
this.ix = [1, 0, -1, 0, 0, 1, 0, -1, -1, 0, 1, 0, 0, 1, 1, 0, 0, 0, 1, 1];
this.grid = [];
this.balls = [];
this.iter = 0;
this.sign = 1;
// init grid
for (var i = 0; i < (this.sx + 2) * (this.sy + 2); i++) {
this.grid[i] = new Point((i % (this.sx + 2)) * this.step, Math.floor(i / (this.sx + 2)) * this.step);
}
// create metaballs
for (var k = 0; k < numBalls; k++) {
this.balls[k] = new Ball(this);
}
}
LavaLamp.prototype.computeForce = function (x, y, idx) {
var force;
var id = idx || x + y * (this.sx + 2);
if (x === 0 || y === 0 || x === this.sx || y === this.sy) {
force = 0.6 * this.sign;
}
else {
force = 0;
var cell = this.grid[id];
var i = 0;
var ball = void 0;
while ((ball = this.balls[i++])) {
force +=
(ball.size * ball.size) /
(-2 * cell.x * ball.pos.x - 2 * cell.y * ball.pos.y + ball.pos.magnitude + cell.magnitude);
}
force *= this.sign;
}
this.grid[id].force = force;
return force;
};
LavaLamp.prototype.marchingSquares = function (next) {
var x = next[0];
var y = next[1];
var pdir = next[2];
var id = x + y * (this.sx + 2);
if (this.grid[id].computed === this.iter) {
return false;
}
var dir;
var mscase = 0;
// neighbors force
for (var i = 0; i < 4; i++) {
var idn = x + this.ix[i + 12] + (y + this.ix[i + 16]) * (this.sx + 2);
var force = this.grid[idn].force;
if ((force > 0 && this.sign < 0) || (force < 0 && this.sign > 0) || !force) {
// compute force if not in buffer
force = this.computeForce(x + this.ix[i + 12], y + this.ix[i + 16], idn);
}
if (Math.abs(force) > 1)
mscase += Math.pow(2, i);
}
if (mscase === 15) {
// inside
return [x, y - 1, false];
}
else {
// ambiguous cases
if (mscase === 5)
dir = pdir === 2 ? 3 : 1;
else if (mscase === 10)
dir = pdir === 3 ? 0 : 2;
else {
// lookup
dir = this.mscases[mscase];
this.grid[id].computed = this.iter;
}
// draw line
var ix = this.step /
(Math.abs(Math.abs(this.grid[x + this.plx[4 * dir + 2] + (y + this.ply[4 * dir + 2]) * (this.sx + 2)].force) -
1) /
Math.abs(Math.abs(this.grid[x + this.plx[4 * dir + 3] + (y + this.ply[4 * dir + 3]) * (this.sx + 2)].force) - 1) +
1);
this.ctx.lineTo(this.grid[x + this.plx[4 * dir] + (y + this.ply[4 * dir]) * (this.sx + 2)].x + this.ix[dir] * ix, this.grid[x + this.plx[4 * dir + 1] + (y + this.ply[4 * dir + 1]) * (this.sx + 2)].y +
this.ix[dir + 4] * ix);
this.paint = true;
// next
return [x + this.ix[dir + 4], y + this.ix[dir + 8], dir];
}
};
LavaLamp.prototype.renderMetaballs = function () {
var i = 0;
var ball;
while ((ball = this.balls[i++]))
ball.move();
// reset grid
this.iter++;
this.sign = -this.sign;
this.paint = false;
this.ctx.fillStyle = this.metaFill;
this.ctx.beginPath();
// compute metaballs
i = 0;
while ((ball = this.balls[i++])) {
// first cell
var next = [Math.round(ball.pos.x / this.step), Math.round(ball.pos.y / this.step), false];
// marching squares
while (next) {
next = this.marchingSquares(next);
}
// fill and close path
if (this.paint) {
this.ctx.fill();
this.ctx.closePath();
this.ctx.beginPath();
this.paint = false;
}
}
};
return LavaLamp;
}());
// gradients
function createRadialGradient(ctx, w, h, r, c0, c1) {
var gradient = ctx.createRadialGradient(w / 1, h / 1, 0, w / 1, h / 1, r);
gradient.addColorStop(0, c0);
gradient.addColorStop(1, c1);
return gradient;
}