We Keep Coding

An error in the checkers code, how to fix it?

Made a small game, the main goal is to remove all the pieces by jumping over the checkers. The first time it is possible to remove the checker, the second time it gives an error?
Uncaught TypeError: Cannot read property 'theRow' of undefined
On line 180. I looked at the line, here it is.
Code:
Point = function(x, y) {
this.x = x;
this.y = y;
}
window.onload = function() {
var canvas;
var context;
var BB;
var offsetX;
var offsetY;
var dragok = false;
var startX;
var startY;
var oldX, oldY;
var fieldArray = [
[1, 0, 1, 1, 0, 0],
[1, 0, 0, 1, 1, 0],
[0, 0, 0, 0, 0, 0]
];
var shapes = [];
var possibleLandings = [];
var localX, localY;
var pickedMonster;
var sx = 0;
var sy = 0;
var i1 = 0;
function draw() {
context.clearRect(0, 0, canvas.width, canvas.height);
context.save();
for (var i = 0; i < fieldArray.length; i++) {
for (var j = 0; j < fieldArray[i].length; j++) {
context.lineWidth = 1;
context.strokeRect(j * 60, i * 60, 60, 60);
context.fillRect(j * 60, i * 60, 60, 60);
}
}
for (var i = 0; i < shapes.length; i++) {
circle(shapes[i]);
}
context.restore();
if (possibleLandings.length > 0) {
context.save();
context.fillStyle = "#4CFF00";
context.fillRect(oldX, oldY, 20, 20);
context.restore();
} else {
context.save();
context.fillStyle = "#FF0000";
context.fillRect(oldX, oldY, 20, 20);
context.restore();
}
}
function circle(c) {
context.fillStyle = c.fill;
context.beginPath();
context.arc(c.x, c.y, c.r, 0, Math.PI * 2);
context.closePath();
context.fill();
}
function myDown(e) {
e.preventDefault();
e.stopPropagation();
var mx = parseInt(e.clientX - offsetX);
var my = parseInt(e.clientY - offsetY);
dragok = false;
for (var i = 0; i < shapes.length; i++) {
var s = shapes[i];
var dx = s.x - mx;
var dy = s.y - my;
if (dx * dx + dy * dy < s.r * s.r) {
dragok = true;
s.isDragging = true;
pickedMonster = {
x: s.x,
y: s.y,
i: i,
theRow: s.theRow,
theCol: s.theCol
};
oldX = s.x;
oldY = s.y;
localX = mx - s.x + (30 / 2);
localY = my - s.y + (30 / 2);
checkMonster(s);
canvas.onmousemove = moveMonster;
canvas.onmouseup = dropMonster;
}
}
startX = mx;
startY = my;
}
function moveMonster(e) {
if (dragok) {
e.preventDefault();
e.stopPropagation();
var mx = parseInt(e.clientX - offsetX);
var my = parseInt(e.clientY - offsetY);
var dx = mx - startX;
var dy = my - startY;
for (var i = 0; i < shapes.length; i++) {
var s = shapes[i];
if (s.isDragging) {
s.x += dx;
s.y += dy;
pickedMonster.x = e.clientX - localX;
pickedMonster.y = e.clientY - localY;
}
}
draw();
startX = mx;
startY = my;
}
}
function dropMonster(e) {
e.preventDefault();
e.stopPropagation();
var legalMove = false;
var dropX = Math.floor((pickedMonster.x + 30) / 60);
var dropY = Math.floor((pickedMonster.y + 30) / 60);
console.log(dropX);
for (var i = 0; i < possibleLandings.length; i++) {
if (possibleLandings[i].x == dropY && possibleLandings[i].y == dropX) {
legalMove = true;
break;
}
}
if (!legalMove) {
shapes[pickedMonster.i].x = oldX;
shapes[pickedMonster.i].y = oldY;
} else {
var rowOffset = (dropY - pickedMonster.theRow) / 2;
var colOffset = (dropX - pickedMonster.theCol) / 2;
fieldArray[pickedMonster.theRow][pickedMonster.theCol] = 0;
fieldArray[pickedMonster.theRow + rowOffset][pickedMonster.theCol + colOffset] = 0;
fieldArray[pickedMonster.theRow + 2 * rowOffset][pickedMonster.theCol + 2 * colOffset] = 1;
for (i = 0; i < 5; i++) {
var currentMonster = shapes[i];
if (currentMonster.theRow == pickedMonster.theRow + rowOffset &&
currentMonster.theCol == pickedMonster.theCol + colOffset) {
shapes.splice(i, 1);
}
}
}
dragok = false;
for (var i = 0; i < shapes.length; i++) {
shapes[i].isDragging = false;
}
draw();
}
function checkMonster(s) {
for (var i = 0; i < 4; i++) {
var deltaRow = (1 - i) * (i % 2 - 1);
var deltaCol = (2 - i) * (i % 2);
if (checkField(s, deltaRow, deltaCol)) {
possibleLandings.push(new Point(s.theRow + 2 * deltaRow, s.theCol + 2 * deltaCol));
}
}
}
function checkField(s, rowOffset, colOffset) {
if (fieldArray[s.theRow + 2 * rowOffset] != undefined &&
fieldArray[s.theRow + 2 * rowOffset][s.theCol + 2 * colOffset] != undefined) {
if (fieldArray[s.theRow + rowOffset][s.theCol + colOffset] == 1 &&
fieldArray[s.theRow + 2 * rowOffset][s.theCol + 2 * colOffset] == 0) {
return true;
}
}
return false;
}
function main() {
canvas = document.getElementById("drawingCanvas"),
context = canvas.getContext("2d");
canvas.style.background = "#A0A0A0"
BB = canvas.getBoundingClientRect();
context.fillStyle = 'rgb(150,190,255)';
context.globalAlpha = 0.7;
offsetX = BB.left;
offsetY = BB.top;
for (var i = 0; i < fieldArray.length; i++) {
for (var j = 0; j < fieldArray[i].length; j++) {
if (fieldArray[i][j] == 1) {
shapes.push({
x: j * 60 + 30,
y: i * 60 + 30,
r: 30,
theRow: i,
theCol: j,
fill: "#444444",
isDragging: false
});
}
}
}
draw();
canvas.onmousedown = myDown;
}
main();
}
<canvas id="drawingCanvas" width="500" height="500">
How to fix?

At the end of the game shapes is empty but you are getting shapes[i]. That would return undefined. And that's what the error means undefined doesn't have a property theRow.
You should maybe rerun main() or only rerun this:
for (var i = 0; i < fieldArray.length; i++) {
for (var j = 0; j < fieldArray[i].length; j++) {
if (fieldArray[i][j] == 1) {
shapes.push({
x: j * 60 + 30,
y: i * 60 + 30,
r: 30,
theRow: i,
theCol: j,
fill: "#444444",
isDragging: false
});
}
}
}

Javascript text particle in canvas slow in firefox but not on chrome (requestAnimationFrame ?)

I'm struggling with the implementation of a text particle in javascript.
My code is working fine with chromium-based browsers (Chromium: 84) but is unexpectedly slow on firefox (79.0).
I've searched a lot, but still don't find a solution and where the problem is.(This is pretty much linked to this Javascript Animation(Canvas) not working in firefox, Edge but works on Chrome).
Here is my codepen:
https://codepen.io/jgazeau/pen/LYNYPYB
function getRandomInt(max) {
return Math.floor(Math.random() * Math.floor(max));
}
function getCssVar(v) {
return getComputedStyle(document.documentElement).getPropertyValue(v);
}
let text404 = '404';
let canvas = document.getElementById('scene');
let ch = canvas.height = canvas.getBoundingClientRect().height;
let cw = canvas.width = canvas.getBoundingClientRect().width;
let sceneBackground = getCssVar('--scene-background');
let context = canvas.getContext('2d');
let previousMouseCoord = {x:0, y:0};
let mouseCoord = {x:0, y:0};
let sceneResize = false;
let particlesCount = 0;
let particles = [];
let colors = [
getCssVar('--particle-color-1'),
getCssVar('--particle-color-2'),
getCssVar('--particle-color-3'),
getCssVar('--particle-color-4'),
getCssVar('--particle-color-5')
];
const dpi = 200;
let Particle = function(x, y) {
this.x = getRandomInt(cw);
this.y = getRandomInt(ch);
this.coord = {x:x, y:y};
this.r = Math.min((getRandomInt((cw / dpi)) + 1), 6);
this.vx = (Math.random() - 0.5) * 100;
this.vy = (Math.random() - 0.5) * 100;
this.accX = 0;
this.accY = 0;
this.friction = Math.random() * 0.05 + 0.90;
this.color = colors[Math.floor(Math.random() * 6)];
}
Particle.prototype.render = function(isDisableMouse) {
this.accX = (this.coord.x - this.x) / 100;
this.accY = (this.coord.y - this.y) / 100;
this.vx += this.accX;
this.vy += this.accY;
this.vx *= this.friction;
this.vy *= this.friction;
this.x += this.vx;
this.y += this.vy;
if (!isDisableMouse) {
let a = this.x - mouseCoord.x;
let b = this.y - mouseCoord.y;
var distance = Math.sqrt(a * a + b * b);
if(distance < (cw / 15)) {
this.accX = (this.x - mouseCoord.x) / 100;
this.accY = (this.y - mouseCoord.y) / 100;
this.vx += this.accX;
this.vy += this.accY;
}
}
context.fillStyle = this.color;
context.beginPath();
context.arc(this.x, this.y, this.r, 0, Math.PI * 2, false);
context.fill();
context.closePath();
}
function onmouseCoordMove(e) {
mouseCoord.x = e.clientX;
mouseCoord.y = e.clientY;
}
function onTouchMove(e) {
if(e.touches.length > 0 ) {
mouseCoord.x = e.touches[0].clientX;
mouseCoord.y = e.touches[0].clientY;
}
}
function onTouchEnd() {
mouseCoord.x = -9999;
mouseCoord.y = -9999;
}
function initScene() {
ch = canvas.height = canvas.getBoundingClientRect().height;
cw = canvas.width = canvas.getBoundingClientRect().width;
context.clearRect(0, 0, canvas.width, canvas.height);
context.font = 'bold ' + (cw / 5) + 'px sans-serif';
context.fillStyle = sceneBackground;
context.textAlign = 'center';
context.fillText(text404, cw / 2, ch / 2);
let imageData = context.getImageData(0, 0, cw, ch).data;
context.clearRect(0, 0, canvas.width, canvas.height);
context.globalCompositeOperation = 'screen';
particles = [];
for(let y = 0; y < ch; y += Math.round(cw / dpi)) {
for(let x = 0; x < cw; x += Math.round(cw / dpi)) {
if(imageData[((x + y * cw) * 4) + 3] > 128){
particles.push(new Particle(x, y));
}
}
}
particlesCount = particles.length;
}
function renderScene() {
context.clearRect(0, 0, canvas.width, canvas.height);
let isDisableMouse = false;
if ((previousMouseCoord.x === mouseCoord.x) && (previousMouseCoord.x === mouseCoord.x)) {
isDisableMouse = true;
} else {
previousMouseCoord.x = mouseCoord.x;
previousMouseCoord.x = mouseCoord.x;
isDisableMouse = false;
}
for (let i = 0; i < particlesCount; i++) {
particles[i].render(isDisableMouse);
}
requestAnimationFrame(renderScene);
};
document.addEventListener('DOMContentLoaded', function() {
initScene();
renderScene();
window.addEventListener('mousemove', onmouseCoordMove);
window.addEventListener('touchmove', onTouchMove);
window.addEventListener('touchend', onTouchEnd);
window.addEventListener('resize', function() {
if (!sceneResize) {
requestAnimationFrame(function() {
initScene();
sceneResize = false;
});
sceneResize = true;
}
});
});
Can anyone know where this slow issue could come from ?
Thanks a lot for your help.

Adding time elapsed to a canvas game in Javascript

I am having a problem with integrating a simple timer to a game I am trying to build for a practice exercise. I have attempted to search for this solution on the internet but my basic knowledge of .js leaves me stuck at this problem. Can anyone help me with a solution to this?
My codepen is located here: https://codepen.io/jankyvision/pen/PoqYEXV
var c = document.createElement("canvas");
var ctx = c.getContext("2d");
c.width = 720;
c.height = 480;
document.body.appendChild(c);
var perm = [];
while (perm.length < 255){
while(perm.includes(val = Math.floor(Math.random()*255)));
perm.push(val);
}
var lerp = (a,b,t) => a + (b-a) * (1-Math.cos(t*Math.PI))/2;
var noise = x=>{
x = x * 0.01 % 254;
return lerp(perm[Math.floor(x)], perm[Math.ceil(x)], x - Math.floor(x));
}
var Player = function(){
this.x = c.width/2;
this.y = 0;
this.ySpeed = 0;
this.rot = 0;
this.rSpeed = 0;
this.img = new Image();
this.img.src = "./images/moto.png";
this.draw = function(){
var p1 = c.height - noise(t + this.x) * 0.25;
var p2 = c.height - noise(t+5 + this.x) * 0.25;
var grounded = 0;
if(p1-12 > this.y){
this.ySpeed += 0.1;
}else{
this.ySpeed -= this.y - (p1-12);
this.y = p1 - 12;
grounded = 1;
}
var angle = Math.atan2((p2-12) - this.y, (this.x+5) - this.x);
this.y += this.ySpeed;
if(!playing || grounded && Math.abs(this.rot) > Math.PI * 0.5){
playing = false;
this.rSpeed = 5;
k.ArrowUp = 1;
this.x -= speed * 5;
}
if(grounded && playing){
this.rot -= (this.rot - angle) * 0.65;
this.rSpeed = this.rSpeed - (angle - this.rot);
}
this.rSpeed += (k.ArrowLeft - k.ArrowRight) * 0.05;
this.rot -= this.rSpeed * 0.1;
if(this.rot > Math.PI) this.rot = -Math.PI;
if(this.rot < -Math.PI) this.rot = Math.PI;
ctx.save();
ctx.translate(this.x, this.y - 3);
ctx.rotate(this.rot);
ctx.drawImage(this.img, -15, -15, 60, 30);
ctx.restore();
}
}
var player = new Player();
var t = 0;
var speed = 0;
var playing = true;
var k = {ArrowUp:0, ArrowDown:0, ArrowLeft:0, ArrowRight:0};
function loop(){
speed -= (speed - (k.ArrowUp - k.ArrowDown)) * 0.01;
t += 10 * speed;
ctx.fillStyle = "#8D5BC2";
ctx.fillRect(0,0,c.width, c.height);
ctx.fillStyle = "rgba(0,0,0,0.1)";
ctx.beginPath();
ctx.moveTo(0, c.height);
for (let i = 0; i < c.width; i++)
ctx.lineTo(i, c.height*0.8 - noise(t + i*5) * 0.25);
ctx.lineTo(c.width, c.height);
ctx.fill();
ctx.fillStyle = "#444";
ctx.beginPath();
ctx.moveTo(0, c.height);
for (let i = 0; i < c.width; i++)
ctx.lineTo(i, c.height - noise(t + i) * 0.25);
ctx.lineTo(c.width, c.height);
ctx.fill();
player.draw();
if(player.x < 0)
restart();
requestAnimationFrame(loop);
}
onkeydown = d=> k[d.key] = 1;
onkeyup = d=> k[d.key] = 0;
function restart(){
player = new Player();
t = 0;
speed = 0;
playing = true;
k = {ArrowUp:0, ArrowDown:0, ArrowLeft:0, ArrowRight:0};
}
loop();
var instructions = document.createElement("div");
instructions.innerHTML += "[up] [down] = accelerate <br> [Left] [Rigth] = rotate";
document.body.appendChild(instructions);

With some help from https://stackoverflow.com/a/16255190/1309377 you are looking at a pretty simple function that uses ctx.fillText() to draw the amount of elapsed seconds onto the canvas.
You want to use the Date() object when doing a timer as it is more accurate than setTimeout or setInterval.
On restart you just set startTime to the current time again.
var c = document.createElement("canvas");
var ctx = c.getContext("2d");
var startTime = new Date();
c.width = 720;
c.height = 480;
document.body.appendChild(c);
var perm = [];
while (perm.length < 255) {
while (perm.includes(val = Math.floor(Math.random() * 255)));
perm.push(val);
}
var lerp = (a, b, t) => a + (b - a) * (1 - Math.cos(t * Math.PI)) / 2;
var noise = x => {
x = x * 0.01 % 254;
return lerp(perm[Math.floor(x)], perm[Math.ceil(x)], x - Math.floor(x));
}
function drawElapsedTime() {
var elapsed = parseInt((new Date() - startTime) / 1000);
ctx.save();
ctx.beginPath();
ctx.fillStyle = "black";
ctx.font = "14px Verdana"
// draw the running time at half opacity
ctx.globalAlpha = 0.50;
ctx.fillText(elapsed + " seconds", 30,30);
ctx.restore();
}
var Player = function() {
this.x = c.width / 2;
this.y = 0;
this.ySpeed = 0;
this.rot = 0;
this.rSpeed = 0;
this.img = new Image();
this.img.src = "https://upload.wikimedia.org/wikipedia/en/3/3b/SpongeBob_SquarePants_character.svg";
this.draw = function() {
var p1 = c.height - noise(t + this.x) * 0.25;
var p2 = c.height - noise(t + 5 + this.x) * 0.25;
var grounded = 0;
if (p1 - 12 > this.y) {
this.ySpeed += 0.1;
} else {
this.ySpeed -= this.y - (p1 - 12);
this.y = p1 - 12;
grounded = 1;
}
var angle = Math.atan2((p2 - 12) - this.y, (this.x + 5) - this.x);
this.y += this.ySpeed;
if (!playing || grounded && Math.abs(this.rot) > Math.PI * 0.5) {
playing = false;
this.rSpeed = 5;
k.ArrowUp = 1;
this.x -= speed * 5;
}
if (grounded && playing) {
this.rot -= (this.rot - angle) * 0.65;
this.rSpeed = this.rSpeed - (angle - this.rot);
}
this.rSpeed += (k.ArrowLeft - k.ArrowRight) * 0.05;
this.rot -= this.rSpeed * 0.1;
if (this.rot > Math.PI) this.rot = -Math.PI;
if (this.rot < -Math.PI) this.rot = Math.PI;
ctx.save();
ctx.translate(this.x, this.y - 3);
ctx.rotate(this.rot);
ctx.drawImage(this.img, -15, -15, 60, 30);
ctx.restore();
}
}
var player = new Player();
var t = 0;
var speed = 0;
var playing = true;
var k = {
ArrowUp: 0,
ArrowDown: 0,
ArrowLeft: 0,
ArrowRight: 0
};
function loop() {
speed -= (speed - (k.ArrowUp - k.ArrowDown)) * 0.01;
t += 10 * speed;
ctx.fillStyle = "#8D5BC2";
ctx.fillRect(0, 0, c.width, c.height);
ctx.fillStyle = "rgba(0,0,0,0.1)";
ctx.beginPath();
ctx.moveTo(0, c.height);
for (let i = 0; i < c.width; i++)
ctx.lineTo(i, c.height * 0.8 - noise(t + i * 5) * 0.25);
ctx.lineTo(c.width, c.height);
ctx.fill();
ctx.fillStyle = "#444";
ctx.beginPath();
ctx.moveTo(0, c.height);
for (let i = 0; i < c.width; i++)
ctx.lineTo(i, c.height - noise(t + i) * 0.25);
ctx.lineTo(c.width, c.height);
ctx.fill();
player.draw();
drawElapsedTime();
if (player.x < 0)
restart();
requestAnimationFrame(loop);
}
onkeydown = d => k[d.key] = 1;
onkeyup = d => k[d.key] = 0;
function restart() {
player = new Player();
startTime = new Date();
t = 0;
speed = 0;
playing = true;
k = {
ArrowUp: 0,
ArrowDown: 0,
ArrowLeft: 0,
ArrowRight: 0
};
}
loop();
var instructions = document.createElement("div");
instructions.innerHTML += "[up] [down] = accelerate <br> [Left] [Rigth] = rotate";
document.body.appendChild(instructions);

var secs = 0;
setInterval(function(){secs++},1000);
this.draw = function(){
// Fill in a rectangle to put the time inside of
ctx.fillStyle="#000000";
ctx.fillRect(10,10,55,25);
ctx.fillStyle="#8D5BC2";
ctx.font = "12px";
// Format the number of seconds - 0:00
timestr = Math.floor(secs/60) + ":";
timestr += ((secs%60<10)&&"0") + secs%60;
// Write the time string over the rectangle
ctx.fillText(timestr,25,25);

Javascript Animation(Canvas) not working in firefox, Edge but works on Chrome

This is a code from codepen. I am trying to work on this one. This code works on chrome but does not work in firefox or edge. I tried to solve the issue but could not fix it. Is the problem with requestAnimationFrame or something else? Can anyone please help? Here is the codepen link: https://codepen.io/iremlopsum/pen/MKNaxd
var canvas = document.querySelector("#scene"),
ctx = canvas.getContext("2d"),
particles = [],
amount = 0,
mouse = {
x: 0,
y: 0
},
radius = 0.7; //Init radius of the force field
var colors = ["rgba(255,255,255, .6)", "rgba(255,255,255, .6)", "rgba(255,255,255, .6)", "rgba(255,255,255, .6)", "rgba(255,255,255, .6)", "rgba(255,255,255, .6)"];
var colorsTwo = ["rgba(255,255,255, .6)", "rgba(255,255,255, .6)", "rgba(255,255,255, .6)", "rgba(255,255,255, .6)", "rgba(255,255,255, .6)", "rgba(255,255,255, .6)"];
var copy = "Mighty Byte"; // Text to display
var initSize = Math.floor(Math.random() * .6) + 1 ;
var hoverSize = initSize + .7;
var ww = canvas.width = window.innerWidth;
var wh = canvas.height = window.innerHeight;
function Particle(x, y) {
this.x = Math.random() * ww;
this.y = Math.random() * wh;
this.dest = {
x: x,
y: y
};
//this.r = Math.random() * 1; // the size of bubbles
this.vx = (Math.random() - 0.5) * 2;
this.vy = (Math.random() - 0.5) * 2;
this.accX = 0;
this.accY = 0;
this.friction = Math.random() * 0.015 + 0.94; // force of bounce, just try to change 0.015 to 0.5
//this.color = colors[Math.floor(Math.random() * 10)];
//this.colorTwo = colorsTwo[Math.floor(Math.random() * 10)];
}
Particle.prototype.render = function() {
this.accX = (this.dest.x - this.x) / 200; //acceleration for X
this.accY = (this.dest.y - this.y) / 200; //acceleration for Y
this.vx += this.accX;
this.vy += this.accY;
this.vx *= this.friction;
this.vy *= this.friction;
this.x += this.vx;
this.y += this.vy;
ctx.fillStyle = this.color;
ctx.beginPath();
ctx.arc(this.x, this.y, this.r, Math.PI * 2, false);
ctx.fill();
var a = this.x - mouse.x;
var b = this.y - mouse.y;
var distance = Math.sqrt(a * a + b * b);
if (distance < (radius * 70)) {
this.accX = (this.x - mouse.x) / 20; //acceleration on mouseover X, smaller faster
this.accY = (this.y - mouse.y) / 20; //acceleration on mouseover Y, smaller faster
this.vx += this.accX;
this.vy += this.accY;
//ctx.fillStyle = this.colorTwo;
}
if (distance < (radius * 70)) {
this.colorTwo = colorsTwo[Math.floor(Math.random() * 10)];
ctx.fillStyle = this.colorTwo;
this.r = hoverSize; // the size of bubbles
}
if (distance > (radius * 70)) {
this.colorOne = colors[Math.floor(Math.random() * 10)];
ctx.fillStyle = this.colorOne;
this.r = initSize
}
}
function onMouseMove(e) {
mouse.x = e.clientX;
mouse.y = e.clientY;
}
function initScene() {
ww = canvas.width = window.innerWidth;
wh = canvas.height = window.innerHeight;
ctx.clearRect(0, 0, canvas.width, canvas.height);
ctx.font = "bold " + (ww / 10) + "px sans-serif"; // Size of the text
ctx.textAlign = "center";
ctx.fillText(copy, ww / 2, wh / 2); //Centering
var data = ctx.getImageData(0, 0, ww, wh).data;
ctx.clearRect(0, 0, canvas.width, canvas.height);
ctx.globalCompositeOperation = "screen";
particles = [];
for (var i = 0; i < ww; i += Math.round(ww / 400)) { //400 here represents the amount of particles
for (var j = 0; j < wh; j += Math.round(ww / 400)) {
if (data[((i + j * ww) * 4) + 3] > 250) {
particles.push(new Particle(i, j));
}
}
}
amount = particles.length;
}
function onMouseClick() {
radius = 4; //onclick expand radius
}
function offMouseClick() {
radius = 0.5; //offClick init radius
}
function delayedInitRadius() {
setTimeout(offMouseClick, 500); //delay for offClick init radius
}
function render(a) {
requestAnimationFrame(render);
ctx.clearRect(0, 0, canvas.width, canvas.height);
for (var i = 0; i < amount; i++) {
particles[i].render();
}
};
window.addEventListener("resize", initScene);
window.addEventListener("mousemove", onMouseMove);
window.addEventListener("mousedown", onMouseClick);
window.addEventListener("mouseup", delayedInitRadius);
initScene();
requestAnimationFrame(render);

Circle animation random color

Hi I try to create an animation with a circle. The function drawRandom(drawFunctions) should pic one of the three drawcircle functions and should bring it on the canvas. Now the problem is that this function become executed every second (main loop) and the circle change his colour. How can I fix that?
window.onload = window.onresize = function() {
var C = 1; // canvas width to viewport width ratio
var el = document.getElementById("myCanvas");
var viewportWidth = window.innerWidth;
var viewportHeight = window.innerHeight;
var canvasWidth = viewportWidth * C;
var canvasHeight = viewportHeight;
el.style.position = "fixed";
el.setAttribute("width", canvasWidth);
el.setAttribute("height", canvasHeight);
var x = canvasWidth / 100;
var y = canvasHeight / 100;
var ballx = canvasWidth / 100;
var n;
window.ctx = el.getContext("2d");
ctx.clearRect(0, 0, canvasWidth, canvasHeight);
// draw triangles
function init() {
ballx;
return setInterval(main_loop, 1000);
}
function drawcircle1()
{
var radius = x * 5;
ctx.beginPath();
ctx.arc(ballx * 108, canvasHeight / 2, radius, 0, 2 * Math.PI, false);
ctx.fillStyle = 'yellow';
ctx.fill();
}
function drawcircle2()
{
var radius = x * 5;
ctx.beginPath();
ctx.arc(ballx * 108, canvasHeight / 2, radius, 0, 2 * Math.PI, false);
ctx.fillStyle = 'blue';
ctx.fill();
}
function drawcircle3()
{
var radius = x * 5;
ctx.beginPath();
ctx.arc(ballx * 105, canvasHeight / 2, radius, 0, 2 * Math.PI, false);
ctx.fillStyle = 'orange';
ctx.fill();
}
function draw() {
var counterClockwise = false;
ctx.clearRect(0, 0, canvasWidth, canvasHeight);
//first halfarc
ctx.beginPath();
ctx.arc(x * 80, y * 80, y * 10, 0 * Math.PI, 1 * Math.PI, counterClockwise);
ctx.lineWidth = y * 1;
ctx.strokeStyle = 'black';
ctx.stroke();
// draw stop button
ctx.beginPath();
ctx.moveTo(x * 87, y * 2);
ctx.lineTo(x * 87, y * 10);
ctx.lineWidth = x;
ctx.stroke();
ctx.beginPath();
ctx.moveTo(x * 95, y * 2);
ctx.lineTo(x * 95, y * 10);
ctx.lineWidth = x;
ctx.stroke();
function drawRandom(drawFunctions){
//generate a random index
var randomIndex = Math.floor(Math.random() * drawFunctions.length);
//call the function
drawFunctions[randomIndex]();
}
drawRandom([drawcircle1, drawcircle2, drawcircle3]);
}
function update() {
ballx -= 0.1;
if (ballx < 0) {
ballx = -radius;
}
}
function main_loop() {
draw();
update();
collisiondetection();
}
init();
function initi() {
console.log('init');
// Get a reference to our touch-sensitive element
var touchzone = document.getElementById("myCanvas");
// Add an event handler for the touchstart event
touchzone.addEventListener("mousedown", touchHandler, false);
}
function touchHandler(event) {
// Get a reference to our coordinates div
var can = document.getElementById("myCanvas");
// Write the coordinates of the touch to the div
if (event.pageX < x * 50 && event.pageY > y * 10) {
ballx += 1;
} else if (event.pageX > x * 50 && event.pageY > y * 10 ) {
ballx -= 1;
}
console.log(event, x, ballx);
draw();
}
initi();
draw();
}

Take a look at my code that I wrote:
var lastTime = 0;
function requestMyAnimationFrame(callback, time)
{
var t = time || 16;
var currTime = new Date().getTime();
var timeToCall = Math.max(0, t - (currTime - lastTime));
var id = window.setTimeout(function(){ callback(currTime + timeToCall); }, timeToCall);
lastTime = currTime + timeToCall;
return id;
}
var canvas = document.getElementById("canvas");
var context = canvas.getContext("2d");
canvas.width = window.innerWidth - 20;
canvas.height = window.innerHeight - 20;
canvas.style.width = canvas.width + "px";
canvas.style.height = canvas.height + "px";
var circles = [];
var mouse =
{
x: 0,
y: 0
}
function getCoordinates(x, y)
{
return "(" + x + ", " + y + ")";
}
function getRatio(n, d)
{
// prevent division by 0
if (d === 0 || n === 0)
{
return 0;
}
else
{
return n/d;
}
}
function Circle(x,y,d,b,s,c)
{
this.x = x;
this.y = y;
this.diameter = Math.round(d);
this.radius = Math.round(d/2);
this.bounciness = b;
this.speed = s;
this.color = c;
this.deltaX = 0;
this.deltaY = 0;
this.drawnPosition = "";
this.fill = function()
{
context.beginPath();
context.arc(this.x+this.radius,this.y+this.radius,this.radius,0,Math.PI*2,false);
context.closePath();
context.fill();
}
this.clear = function()
{
context.fillStyle = "#ffffff";
this.fill();
}
this.draw = function()
{
if (this.drawnPosition !== getCoordinates(this.x, this.y))
{
context.fillStyle = this.color;
// if commented, the circle will be drawn if it is in the same position
//this.drawnPosition = getCoordinates(this.x, this.y);
this.fill();
}
}
this.keepInBounds = function()
{
if (this.x < 0)
{
this.x = 0;
this.deltaX *= -1 * this.bounciness;
}
else if (this.x + this.diameter > canvas.width)
{
this.x = canvas.width - this.diameter;
this.deltaX *= -1 * this.bounciness;
}
if (this.y < 0)
{
this.y = 0;
this.deltaY *= -1 * this.bounciness;
}
else if (this.y+this.diameter > canvas.height)
{
this.y = canvas.height - this.diameter;
this.deltaY *= -1 * this.bounciness;
}
}
this.followMouse = function()
{
// deltaX/deltaY will currently cause the circles to "orbit" around the cursor forever unless it hits a wall
var centerX = Math.round(this.x + this.radius);
var centerY = Math.round(this.y + this.radius);
if (centerX < mouse.x)
{
// circle is to the left of the mouse, so move the circle to the right
this.deltaX += this.speed;
}
else if (centerX > mouse.x)
{
// circle is to the right of the mouse, so move the circle to the left
this.deltaX -= this.speed;
}
else
{
//this.deltaX = 0;
}
if (centerY < mouse.y)
{
// circle is above the mouse, so move the circle downwards
this.deltaY += this.speed;
}
else if (centerY > mouse.y)
{
// circle is under the mouse, so move the circle upwards
this.deltaY -= this.speed;
}
else
{
//this.deltaY = 0;
}
this.x += this.deltaX;
this.y += this.deltaY;
this.x = Math.round(this.x);
this.y = Math.round(this.y);
}
}
function getRandomDecimal(min, max)
{
return Math.random() * (max-min) + min;
}
function getRoundedNum(min, max)
{
return Math.round(getRandomDecimal(min, max));
}
function getRandomColor()
{
// array of three colors
var colors = [];
// go through loop and add three integers between 0 and 255 (min and max color values)
for (var i = 0; i < 3; i++)
{
colors[i] = getRoundedNum(0, 255);
}
// return rgb value (RED, GREEN, BLUE)
return "rgb(" + colors[0] + "," + colors[1] + ", " + colors[2] + ")";
}
function createCircle(i)
{
// diameter of circle
var minDiameter = 25;
var maxDiameter = 50;
// bounciness of circle (changes speed if it hits a wall)
var minBounciness = 0.2;
var maxBounciness = 0.65;
// speed of circle (how fast it moves)
var minSpeed = 0.3;
var maxSpeed = 0.45;
// getRoundedNum returns a random integer and getRandomDecimal returns a random decimal
var x = getRoundedNum(0, canvas.width);
var y = getRoundedNum(0, canvas.height);
var d = getRoundedNum(minDiameter, maxDiameter);
var c = getRandomColor();
var b = getRandomDecimal(minBounciness, maxBounciness);
var s = getRandomDecimal(minSpeed, maxSpeed);
// create the circle with x, y, diameter, bounciness, speed, and color
circles[i] = new Circle(x,y,d,b,s,c);
}
function makeCircles()
{
var maxCircles = getRoundedNum(2, 5);
for (var i = 0; i < maxCircles; i++)
{
createCircle(i);
}
}
function drawCircles()
{
var ii = 0;
for (var i = 0; ii < circles.length; i++)
{
if (circles[i])
{
circles[i].draw();
ii++;
}
}
}
function clearCircles()
{
var ii = 0;
for (var i = 0; ii < circles.length; i++)
{
if (circles[i])
{
circles[i].clear();
ii++;
}
}
}
function updateCircles()
{
var ii = 0;
for (var i = 0; ii < circles.length; i++)
{
if (circles[i])
{
circles[i].keepInBounds();
circles[i].followMouse();
ii++;
}
}
}
function update()
{
requestMyAnimationFrame(update,10);
updateCircles();
}
function draw()
{
requestMyAnimationFrame(draw,1000/60);
context.clearRect(0,0,canvas.width,canvas.height);
drawCircles();
}
window.addEventListener("load", function()
{
window.addEventListener("mousemove", function(e)
{
mouse.x = e.layerX || e.offsetX;
mouse.y = e.layerY || e.offsetY;
});
makeCircles();
update();
draw();
});