Skip to content

Instantly share code, notes, and snippets.

@navyasn

navyasn/index.html

Created December 20, 2019 08:58
Show Gist options
  • Save navyasn/662f0a5059fe3826d38964a4316667ee to your computer and use it in GitHub Desktop.
Save navyasn/662f0a5059fe3826d38964a4316667ee to your computer and use it in GitHub Desktop.
Download ZIP
Bouncing balls // source https://jsbin.com/bolicij
Raw
index.html
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Bouncing balls</title>
<link rel="stylesheet" href="style.css">
<style id="jsbin-css">
html, body {
margin: 0;
}
html {
font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif;
height: 100%;
}
body {
overflow: hidden;
height: inherit;
}
h1 {
font-size: 2rem;
letter-spacing: -1px;
position: absolute;
margin: 0;
top: -4px;
right: 5px;
color: transparent;
text-shadow: 0 0 4px white;
}
p {
position: absolute;
margin: 0;
top: 35px;
right: 5px;
color: #aaa;
}
</style>
</head>
<body>
<h1>bouncing balls</h1>
<p>Ball count: </p>
<canvas></canvas>
<script src="main-finished.js"></script>
<script id="jsbin-javascript">
// define variable for ball count paragraph
const para = document.querySelector('p');
let count = 0;
// setup canvas
const canvas = document.querySelector('canvas');
const ctx = canvas.getContext('2d');
const width = canvas.width = window.innerWidth;
const height = canvas.height = window.innerHeight;
// function to generate random number
function random(min,max) {
const num = Math.floor(Math.random()*(max-min)) + min;
return num;
}
// define shape constructor
function Shape(x, y, velX, velY, exists) {
this.x = x;
this.y = y;
this.velX = velX;
this.velY = velY;
this.exists = exists;
}
// define Ball constructor, inheriting from Shape
function Ball(x, y, velX, velY, exists, color, size) {
Shape.call(this, x, y, velX, velY, exists);
this.color = color;
this.size = size;
}
Ball.prototype = Object.create(Shape.prototype);
Ball.prototype.constructor = Ball;
// define ball draw method
Ball.prototype.draw = function() {
ctx.beginPath();
ctx.fillStyle = this.color;
ctx.arc(this.x, this.y, this.size, 0, 2 * Math.PI);
ctx.fill();
};
// define ball update method
Ball.prototype.update = function() {
if((this.x + this.size) >= width) {
this.velX = -(this.velX);
}
if((this.x - this.size) <= 0) {
this.velX = -(this.velX);
}
if((this.y + this.size) >= height) {
this.velY = -(this.velY);
}
if((this.y - this.size) <= 0) {
this.velY = -(this.velY);
}
this.x += this.velX;
this.y += this.velY;
};
// define ball collision detection
Ball.prototype.collisionDetect = function() {
for(var j = 0; j < balls.length; j++) {
if(!(this === balls[j])) {
var dx = this.x - balls[j].x;
var dy = this.y - balls[j].y;
var distance = Math.sqrt(dx * dx + dy * dy);
if (distance < this.size + balls[j].size && balls[j].exists) {
balls[j].color = this.color = 'rgb(' + random(0,255) + ',' + random(0,255) + ',' + random(0,255) +')';
}
}
}
};
// define EvilCircle constructor, inheriting from Shape
function EvilCircle(x, y, exists) {
Shape.call(this, x, y, 20, 20, exists);
this.color = 'white';
this.size = 10;
}
EvilCircle.prototype = Object.create(Shape.prototype);
EvilCircle.prototype.constructor = EvilCircle;
// define EvilCircle draw method
EvilCircle.prototype.draw = function() {
ctx.beginPath();
ctx.strokeStyle = this.color;
ctx.lineWidth = 3;
ctx.arc(this.x, this.y, this.size, 0, 2 * Math.PI);
ctx.stroke();
};
// define EvilCircle checkBounds method
EvilCircle.prototype.checkBounds = function() {
if((this.x + this.size) >= width) {
this.x -= this.size;
}
if((this.x - this.size) <= 0) {
this.x += this.size;
}
if((this.y + this.size) >= height) {
this.y -= this.size;
}
if((this.y - this.size) <= 0) {
this.y += this.size;
}
};
// define EvilCircle setControls method
EvilCircle.prototype.setControls = function() {
var _this = this;
window.onkeydown = function(e) {
if(e.key === 'a') {
_this.x -= _this.velX;
} else if(e.key === 'd') {
_this.x += _this.velX;
} else if(e.key === 'w') {
_this.y -= _this.velY;
} else if(e.key === 's') {
_this.y += _this.velY;
}
};
};
// define EvilCircle collision detection
EvilCircle.prototype.collisionDetect = function() {
for(let j = 0; j < balls.length; j++) {
if( balls[j].exists ) {
const dx = this.x - balls[j].x;
const dy = this.y - balls[j].y;
const distance = Math.sqrt(dx * dx + dy * dy);
if (distance < this.size + balls[j].size) {
balls[j].exists = false;
count--;
para.textContent = 'Ball count: ' + count;
}
}
}
};
// define array to store balls and populate it
const balls = [];
while(balls.length < 25) {
const size = random(10,20);
let ball = new Ball(
// ball position always drawn at least one ball width
// away from the adge of the canvas, to avoid drawing errors
random(0 + size,width - size),
random(0 + size,height - size),
random(-7,7),
random(-7,7),
true,
'rgb(' + random(0,255) + ',' + random(0,255) + ',' + random(0,255) +')',
size
);
balls.push(ball);
count++;
para.textContent = 'Ball count: ' + count;
}
// define loop that keeps drawing the scene constantly
let evil = new EvilCircle(random(0,width), random(0,height), true);
evil.setControls();
function loop() {
ctx.fillStyle = 'rgba(0,0,0,0.25)';
ctx.fillRect(0,0,width,height);
for(let i = 0; i < balls.length; i++) {
if(balls[i].exists) {
balls[i].draw();
balls[i].update();
balls[i].collisionDetect();
}
}
evil.draw();
evil.checkBounds();
evil.collisionDetect();
requestAnimationFrame(loop);
}
loop();
</script>
<script id="jsbin-source-css" type="text/css">html, body {
margin: 0;
}
html {
font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif;
height: 100%;
}
body {
overflow: hidden;
height: inherit;
}
h1 {
font-size: 2rem;
letter-spacing: -1px;
position: absolute;
margin: 0;
top: -4px;
right: 5px;
color: transparent;
text-shadow: 0 0 4px white;
}
p {
position: absolute;
margin: 0;
top: 35px;
right: 5px;
color: #aaa;
}</script>
<script id="jsbin-source-javascript" type="text/javascript">// define variable for ball count paragraph
const para = document.querySelector('p');
let count = 0;
// setup canvas
const canvas = document.querySelector('canvas');
const ctx = canvas.getContext('2d');
const width = canvas.width = window.innerWidth;
const height = canvas.height = window.innerHeight;
// function to generate random number
function random(min,max) {
const num = Math.floor(Math.random()*(max-min)) + min;
return num;
}
// define shape constructor
function Shape(x, y, velX, velY, exists) {
this.x = x;
this.y = y;
this.velX = velX;
this.velY = velY;
this.exists = exists;
}
// define Ball constructor, inheriting from Shape
function Ball(x, y, velX, velY, exists, color, size) {
Shape.call(this, x, y, velX, velY, exists);
this.color = color;
this.size = size;
}
Ball.prototype = Object.create(Shape.prototype);
Ball.prototype.constructor = Ball;
// define ball draw method
Ball.prototype.draw = function() {
ctx.beginPath();
ctx.fillStyle = this.color;
ctx.arc(this.x, this.y, this.size, 0, 2 * Math.PI);
ctx.fill();
};
// define ball update method
Ball.prototype.update = function() {
if((this.x + this.size) >= width) {
this.velX = -(this.velX);
}
if((this.x - this.size) <= 0) {
this.velX = -(this.velX);
}
if((this.y + this.size) >= height) {
this.velY = -(this.velY);
}
if((this.y - this.size) <= 0) {
this.velY = -(this.velY);
}
this.x += this.velX;
this.y += this.velY;
};
// define ball collision detection
Ball.prototype.collisionDetect = function() {
for(var j = 0; j < balls.length; j++) {
if(!(this === balls[j])) {
var dx = this.x - balls[j].x;
var dy = this.y - balls[j].y;
var distance = Math.sqrt(dx * dx + dy * dy);
if (distance < this.size + balls[j].size && balls[j].exists) {
balls[j].color = this.color = 'rgb(' + random(0,255) + ',' + random(0,255) + ',' + random(0,255) +')';
}
}
}
};
// define EvilCircle constructor, inheriting from Shape
function EvilCircle(x, y, exists) {
Shape.call(this, x, y, 20, 20, exists);
this.color = 'white';
this.size = 10;
}
EvilCircle.prototype = Object.create(Shape.prototype);
EvilCircle.prototype.constructor = EvilCircle;
// define EvilCircle draw method
EvilCircle.prototype.draw = function() {
ctx.beginPath();
ctx.strokeStyle = this.color;
ctx.lineWidth = 3;
ctx.arc(this.x, this.y, this.size, 0, 2 * Math.PI);
ctx.stroke();
};
// define EvilCircle checkBounds method
EvilCircle.prototype.checkBounds = function() {
if((this.x + this.size) >= width) {
this.x -= this.size;
}
if((this.x - this.size) <= 0) {
this.x += this.size;
}
if((this.y + this.size) >= height) {
this.y -= this.size;
}
if((this.y - this.size) <= 0) {
this.y += this.size;
}
};
// define EvilCircle setControls method
EvilCircle.prototype.setControls = function() {
var _this = this;
window.onkeydown = function(e) {
if(e.key === 'a') {
_this.x -= _this.velX;
} else if(e.key === 'd') {
_this.x += _this.velX;
} else if(e.key === 'w') {
_this.y -= _this.velY;
} else if(e.key === 's') {
_this.y += _this.velY;
}
};
};
// define EvilCircle collision detection
EvilCircle.prototype.collisionDetect = function() {
for(let j = 0; j < balls.length; j++) {
if( balls[j].exists ) {
const dx = this.x - balls[j].x;
const dy = this.y - balls[j].y;
const distance = Math.sqrt(dx * dx + dy * dy);
if (distance < this.size + balls[j].size) {
balls[j].exists = false;
count--;
para.textContent = 'Ball count: ' + count;
}
}
}
};
// define array to store balls and populate it
const balls = [];
while(balls.length < 25) {
const size = random(10,20);
let ball = new Ball(
// ball position always drawn at least one ball width
// away from the adge of the canvas, to avoid drawing errors
random(0 + size,width - size),
random(0 + size,height - size),
random(-7,7),
random(-7,7),
true,
'rgb(' + random(0,255) + ',' + random(0,255) + ',' + random(0,255) +')',
size
);
balls.push(ball);
count++;
para.textContent = 'Ball count: ' + count;
}
// define loop that keeps drawing the scene constantly
let evil = new EvilCircle(random(0,width), random(0,height), true);
evil.setControls();
function loop() {
ctx.fillStyle = 'rgba(0,0,0,0.25)';
ctx.fillRect(0,0,width,height);
for(let i = 0; i < balls.length; i++) {
if(balls[i].exists) {
balls[i].draw();
balls[i].update();
balls[i].collisionDetect();
}
}
evil.draw();
evil.checkBounds();
evil.collisionDetect();
requestAnimationFrame(loop);
}
loop();
</script></body>
</html>
Raw
jsbin.bolicij.css
html, body {
margin: 0;
}
html {
font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif;
height: 100%;
}
body {
overflow: hidden;
height: inherit;
}
h1 {
font-size: 2rem;
letter-spacing: -1px;
position: absolute;
margin: 0;
top: -4px;
right: 5px;
color: transparent;
text-shadow: 0 0 4px white;
}
p {
position: absolute;
margin: 0;
top: 35px;
right: 5px;
color: #aaa;
}
Raw
jsbin.bolicij.js
// define variable for ball count paragraph
const para = document.querySelector('p');
let count = 0;
// setup canvas
const canvas = document.querySelector('canvas');
const ctx = canvas.getContext('2d');
const width = canvas.width = window.innerWidth;
const height = canvas.height = window.innerHeight;
// function to generate random number
function random(min,max) {
const num = Math.floor(Math.random()*(max-min)) + min;
return num;
}
// define shape constructor
function Shape(x, y, velX, velY, exists) {
this.x = x;
this.y = y;
this.velX = velX;
this.velY = velY;
this.exists = exists;
}
// define Ball constructor, inheriting from Shape
function Ball(x, y, velX, velY, exists, color, size) {
Shape.call(this, x, y, velX, velY, exists);
this.color = color;
this.size = size;
}
Ball.prototype = Object.create(Shape.prototype);
Ball.prototype.constructor = Ball;
// define ball draw method
Ball.prototype.draw = function() {
ctx.beginPath();
ctx.fillStyle = this.color;
ctx.arc(this.x, this.y, this.size, 0, 2 * Math.PI);
ctx.fill();
};
// define ball update method
Ball.prototype.update = function() {
if((this.x + this.size) >= width) {
this.velX = -(this.velX);
}
if((this.x - this.size) <= 0) {
this.velX = -(this.velX);
}
if((this.y + this.size) >= height) {
this.velY = -(this.velY);
}
if((this.y - this.size) <= 0) {
this.velY = -(this.velY);
}
this.x += this.velX;
this.y += this.velY;
};
// define ball collision detection
Ball.prototype.collisionDetect = function() {
for(var j = 0; j < balls.length; j++) {
if(!(this === balls[j])) {
var dx = this.x - balls[j].x;
var dy = this.y - balls[j].y;
var distance = Math.sqrt(dx * dx + dy * dy);
if (distance < this.size + balls[j].size && balls[j].exists) {
balls[j].color = this.color = 'rgb(' + random(0,255) + ',' + random(0,255) + ',' + random(0,255) +')';
}
}
}
};
// define EvilCircle constructor, inheriting from Shape
function EvilCircle(x, y, exists) {
Shape.call(this, x, y, 20, 20, exists);
this.color = 'white';
this.size = 10;
}
EvilCircle.prototype = Object.create(Shape.prototype);
EvilCircle.prototype.constructor = EvilCircle;
// define EvilCircle draw method
EvilCircle.prototype.draw = function() {
ctx.beginPath();
ctx.strokeStyle = this.color;
ctx.lineWidth = 3;
ctx.arc(this.x, this.y, this.size, 0, 2 * Math.PI);
ctx.stroke();
};
// define EvilCircle checkBounds method
EvilCircle.prototype.checkBounds = function() {
if((this.x + this.size) >= width) {
this.x -= this.size;
}
if((this.x - this.size) <= 0) {
this.x += this.size;
}
if((this.y + this.size) >= height) {
this.y -= this.size;
}
if((this.y - this.size) <= 0) {
this.y += this.size;
}
};
// define EvilCircle setControls method
EvilCircle.prototype.setControls = function() {
var _this = this;
window.onkeydown = function(e) {
if(e.key === 'a') {
_this.x -= _this.velX;
} else if(e.key === 'd') {
_this.x += _this.velX;
} else if(e.key === 'w') {
_this.y -= _this.velY;
} else if(e.key === 's') {
_this.y += _this.velY;
}
};
};
// define EvilCircle collision detection
EvilCircle.prototype.collisionDetect = function() {
for(let j = 0; j < balls.length; j++) {
if( balls[j].exists ) {
const dx = this.x - balls[j].x;
const dy = this.y - balls[j].y;
const distance = Math.sqrt(dx * dx + dy * dy);
if (distance < this.size + balls[j].size) {
balls[j].exists = false;
count--;
para.textContent = 'Ball count: ' + count;
}
}
}
};
// define array to store balls and populate it
const balls = [];
while(balls.length < 25) {
const size = random(10,20);
let ball = new Ball(
// ball position always drawn at least one ball width
// away from the adge of the canvas, to avoid drawing errors
random(0 + size,width - size),
random(0 + size,height - size),
random(-7,7),
random(-7,7),
true,
'rgb(' + random(0,255) + ',' + random(0,255) + ',' + random(0,255) +')',
size
);
balls.push(ball);
count++;
para.textContent = 'Ball count: ' + count;
}
// define loop that keeps drawing the scene constantly
let evil = new EvilCircle(random(0,width), random(0,height), true);
evil.setControls();
function loop() {
ctx.fillStyle = 'rgba(0,0,0,0.25)';
ctx.fillRect(0,0,width,height);
for(let i = 0; i < balls.length; i++) {
if(balls[i].exists) {
balls[i].draw();
balls[i].update();
balls[i].collisionDetect();
}
}
evil.draw();
evil.checkBounds();
evil.collisionDetect();
requestAnimationFrame(loop);
}
loop();
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment