Develop Reference

button won't change color

I have made 30 buttons in JavaScript now I want all buttons to be green like the first button and whenever you click on a button it turns and stays red.
For some reason only the first button is green and whenever I click it it won't turn red. I tried using: button.style.backgroundColor = "red"; in a function to make the button red when clicked but this doesn't work
const color = ["green"];
page();
function onbuttonclicked() {
document.body.style.backgroundColor = color[nr - 1];
}
function page() {
document.body.style.backgroundColor = "grey";
//style page
createButtons(30);
}
function set_onclick(amount) {
for (var a = 1; a < (amount + 1); a++) {
document.getElementById("button" + a).setAttribute("onclick", "onbuttonclicked(" + a + ")");
}
}
function createButtons(amount) {
for (var a = 1; a < (amount + 1); a++) {
var button = document.createElement("button");
button.style.backgroundColor = color[a - 1];
button.id = "button" + a;
button.innerHTML = "button " + a;
container.appendChild(button);
}
set_onclick(amount);
}
<div id="container"></div>
EDIT
thanks for all the answers it isnt possible to only change certain buttons when you click on them right? so when i click on button1 nothing happens but whenever i click on button 3 it turn red

You need to pass nr as a parameter in onbuttonclicked function
EDIT:
OP Comment:
okay so i need to add an parameter. but i want all 30 buttons to be green so when you open the page all buttons are green this also has to do with the parameter?
For that in your loop createButton, change color[a - 1] for color[0]
const color = ["green"];
function onbuttonclicked(nr) {
document.body.style.backgroundColor = color[nr - 1];
}
function page() {
//style page
document.body.style.backgroundColor = "grey";
createButtons(30);
}
function set_onclick(amount, nr) {
for (let a = 1; a < (amount + 1); a++) {
document.getElementById(`button${a}`).setAttribute("onclick", `onbuttonclicked(${nr})`);
}
}
function createButtons(amount) {
for (let a = 1; a < (amount + 1); a++) {
const button = document.createElement("button");
button.style.backgroundColor = color[0];
button.id = `button${a}`;
button.innerHTML = `button ${a}`;
container.appendChild(button);
}
set_onclick(amount, 1);
}
page();
<div id="container"></div>

const number_of_buttons = 30;
createButtons();
function createButtons(){
var container = document.getElementById("container");
for(var i=1;i<=number_of_buttons;i++){
var button = document.createElement("button");
button.innerText = "Button " + i;
button.style.backgroundColor = "green";
button.onclick = function(event){
var source = event.target || event.srcElementl
source.style.backgroundColor = "red";
};
container.appendChild(button);
}
}
button{
margin: 10px;
font-family: 'Consolas';
font-size: 20px;
padding: 5px;
outline: none;
cursor: pointer;
transition: 0.5s;
}
button:hover{
border: 1px solid black;
}
button:active{
transform: translateY(2px);
}
<div id="container">
</div>
This is what you have asked for!
I did the styling for better looks!

This line: button.style.backgroundColor = color[a - 1]; is wrong, since your color array only contains a single string ("green"). You should do color[0], or, you need to populate the array to have 30 elements.
document.body.style.backgroundColor = color[nr - 1]; - Where is this nr variable came from? The correct line should be button.style.backgroundColor = "red"; or - again - you can populate the color (i.e const color=["green", "red"]) and use color[1].
Check out this demo

A common way to do this is to use CSS classes:
page();
function onbuttonclicked(a) {
//document.body.style.backgroundColor = color[nr - 1];
document.getElementById("button" + a).classList.remove("button")
document.getElementById("button" + a).classList.add("clickedbutton")
}
function set_onclick(amount) {
for (var a = 1; a < (amount + 1); a++) {
document.getElementById("button" + a).setAttribute("onclick", "onbuttonclicked(" + a + ")");
}
}
function page() {
document.body.style.backgroundColor = "grey";
//style page
createButtons(30);
}
function createButtons(amount){
for (var a = 1;a <(amount + 1); a++) {
var button = document.createElement("button");
button.classList.add("button")
button.id = "button" + a;
button.innerHTML = "button " + a;
container.appendChild(button);
}
set_onclick(amount);
}
.clickedbutton {
background-color: red;
}
.button {
background-color: green;
}
<div id="container"></div>

Using nested setTimeout to create an animated selection sort

I am working on a basic sorting visualizer with using only HTML, CSS, and JS, and I've run into a problem with the animation aspect. To initialize the array, I generate random numbers within some specified range and push them on to the array. Then based on the webpage dimensions, I create divs for each element and give each one height and width dimensions accordingly, and append each to my "bar-container" div currently in the dom.
function renderVisualizer() {
var barContainer = document.getElementById("bar-container");
//Empties bar-container div
while (barContainer.hasChildNodes()) {
barContainer.removeChild(barContainer.lastChild);
}
var heightMult = barContainer.offsetHeight / max_element;
var temp = barContainer.offsetWidth / array.length;
var barWidth = temp * 0.9;
var margin = temp * 0.05;
//Creating array element bars
for (var i = 0; i < array.length; i++) {
var arrayBar = document.createElement("div");
arrayBar.className = "array-bar"
if (barWidth > 30)
arrayBar.textContent = array[i];
//Style
arrayBar.style.textAlign = "center";
arrayBar.style.height = array[i] * heightMult + "px";
arrayBar.style.width = barWidth;
arrayBar.style.margin = margin;
barContainer.appendChild(arrayBar);
}
}
I wrote the following animated selection sort and it works well, but the only "animated" portion is in the outer for-loop, and I am not highlighting bars as I traverse through them.
function selectionSortAnimated() {
var barContainer = document.getElementById("bar-container");
var barArr = barContainer.childNodes;
for (let i = 0; i < barArr.length - 1; i++) {
let min_idx = i;
let minNum = parseInt(barArr[i].textContent);
for (let j = i + 1; j < barArr.length; j++) {
let jNum = parseInt(barArr[j].textContent, 10);
if (jNum < minNum) {
min_idx = j;
minNum = jNum;
}
}
//setTimeout(() => {
barContainer.insertBefore(barArr[i], barArr[min_idx])
barContainer.insertBefore(barArr[min_idx], barArr[i]);
//}, i * 500);
}
}
I am trying to use nested setTimeout calls to highlight each bar as I traverse through it, then swap the bars, but I'm running into an issue. I'm using idxContainer object to store my minimum index, but after each run of innerLoopHelper, it ends up being equal to i and thus there is no swap. I have been stuck here for a few hours and am utterly confused.
function selectionSortTest() {
var barContainer = document.getElementById("bar-container");
var barArr = barContainer.childNodes;
outerLoopHelper(0, barArr, barContainer);
console.log(array);
}
function outerLoopHelper(i, barArr, barContainer) {
if (i < array.length - 1) {
setTimeout(() => {
var idxContainer = {
idx: i
};
innerLoopHelper(i + 1, idxContainer, barArr);
console.log(idxContainer);
let minIdx = idxContainer.idx;
let temp = array[minIdx];
array[minIdx] = array[i];
array[i] = temp;
barContainer.insertBefore(barArr[i], barArr[minIdx])
barContainer.insertBefore(barArr[minIdx], barArr[i]);
//console.log("Swapping indices: " + i + " and " + minIdx);
outerLoopHelper(++i, barArr, barContainer);
}, 100);
}
}
function innerLoopHelper(j, idxContainer, barArr) {
if (j < array.length) {
setTimeout(() => {
if (j - 1 >= 0)
barArr[j - 1].style.backgroundColor = "gray";
barArr[j].style.backgroundColor = "red";
if (array[j] < array[idxContainer.idx])
idxContainer.idx = j;
innerLoopHelper(++j, idxContainer, barArr);
}, 100);
}
}
I know this is a long post, but I just wanted to be as specific as possible. Thank you so much for reading, and any guidance will be appreciated!

Convert your sorting function to a generator function*, this way, you can yield it the time you update your rendering:
const sorter = selectionSortAnimated();
const array = Array.from( { length: 100 }, ()=> Math.round(Math.random()*50));
const max_element = 50;
renderVisualizer();
anim();
// The animation loop
// simply calls itself until our generator function is done
function anim() {
if( !sorter.next().done ) {
// schedules callback to before the next screen refresh
// usually 60FPS, it may vary from one monitor to an other
requestAnimationFrame( anim );
// you could also very well use setTimeout( anim, t );
}
}
// Converted to a generator function
function* selectionSortAnimated() {
const barContainer = document.getElementById("bar-container");
const barArr = barContainer.children;
for (let i = 0; i < barArr.length - 1; i++) {
let min_idx = i;
let minNum = parseInt(barArr[i].textContent);
for (let j = i + 1; j < barArr.length; j++) {
let jNum = parseInt(barArr[j].textContent, 10);
if (jNum < minNum) {
barArr[min_idx].classList.remove( 'selected' );
min_idx = j;
minNum = jNum;
barArr[min_idx].classList.add( 'selected' );
}
// highlight
barArr[j].classList.add( 'checking' );
yield; // tell the outer world we are paused
// once we start again
barArr[j].classList.remove( 'checking' );
}
barArr[min_idx].classList.remove( 'selected' );
barContainer.insertBefore(barArr[i], barArr[min_idx])
barContainer.insertBefore(barArr[min_idx], barArr[i]);
// pause here too?
yield;
}
}
// same as OP
function renderVisualizer() {
const barContainer = document.getElementById("bar-container");
//Empties bar-container div
while (barContainer.hasChildNodes()) {
barContainer.removeChild(barContainer.lastChild);
}
var heightMult = barContainer.offsetHeight / max_element;
var temp = barContainer.offsetWidth / array.length;
var barWidth = temp * 0.9;
var margin = temp * 0.05;
//Creating array element bars
for (var i = 0; i < array.length; i++) {
var arrayBar = document.createElement("div");
arrayBar.className = "array-bar"
if (barWidth > 30)
arrayBar.textContent = array[i];
//Style
arrayBar.style.textAlign = "center";
arrayBar.style.height = array[i] * heightMult + "px";
arrayBar.style.width = barWidth;
arrayBar.style.margin = margin;
barContainer.appendChild(arrayBar);
}
}
#bar-container {
height: 250px;
white-space: nowrap;
width: 3500px;
}
.array-bar {
border: 1px solid;
width: 30px;
display: inline-block;
background-color: #00000022;
}
.checking {
background-color: green;
}
.selected, .checking.selected {
background-color: red;
}
<div id="bar-container"></div>

So I thought about this, and it's a little tricky, what I would do is just store the indexes of each swap as you do the sort, and then do all of the animation seperately, something like this:
// how many elements we want to sort
const SIZE = 24;
// helper function to get a random number
function getRandomInt() {
return Math.floor(Math.random() * Math.floor(100));
}
// this will hold all of the swaps of the sort.
let steps = [];
// the data we are going to sort
let data = new Array(SIZE).fill(null).map(getRandomInt);
// and a copy that we'll use for animating, this will simplify
// things since we can just run the sort to get the steps and
// not have to worry about timing yet.
let copy = [...data];
let selectionSort = (arr) => {
let len = arr.length;
for (let i = 0; i < len; i++) {
let min = i;
for (let j = i + 1; j < len; j++) {
if (arr[min] > arr[j]) {
min = j;
}
}
if (min !== i) {
let tmp = arr[i];
// save the indexes to swap
steps.push({i1: i, i2: min});
arr[i] = arr[min];
arr[min] = tmp;
}
}
return arr;
}
// sort the data
selectionSort(data);
const container = document.getElementById('container');
let render = (data) => {
// initial render...
data.forEach((el, index) => {
const div = document.createElement('div');
div.classList.add('item');
div.id=`i${index}`;
div.style.left = `${2 + (index * 4)}%`;
div.style.top = `${(98 - (el * .8))}%`
div.style.height = `${el * .8}%`
container.appendChild(div);
});
}
render(copy);
let el1, el2;
const interval = setInterval(() => {
// get the next step
const {i1, i2} = steps.shift();
if (el1) el1.classList.remove('active');
if (el2) el2.classList.remove('active');
el1 = document.getElementById(`i${i1}`);
el2 = document.getElementById(`i${i2}`);
el1.classList.add('active');
el2.classList.add('active');
[el1.id, el2.id] = [el2.id, el1.id];
[el1.style.left, el2.style.left] = [el2.style.left, el1.style.left]
if (!steps.length) {
clearInterval(interval);
document.querySelectorAll('.item').forEach((el) => el.classList.add('active'));
}
}, 1000);
#container {
border: solid 1px black;
box-sizing: border-box;
padding: 20px;
height: 200px;
width: 100%;
background: #EEE;
position: relative;
}
#container .item {
position: absolute;
display: inline-block;
padding: 0;
margin: 0;
width: 3%;
height: 80%;
background: #cafdac;
border: solid 1px black;
transition: 1s;
}
#container .item.active {
background: green;
}
<div id="container"></div>

Unable to update image position in css using javascript

There are some runner(animation-image) in my program which move from position x to y when clicked on start button, i want to add a (reverse)button on completion that when clicked on that the image moves from y to x.
Here is the link of my js-fiddle: https://jsfiddle.net/o6egL4qr/
I have added the reverse button but when clicked on that the image doesn't move at all.
class raceManager {
raceCount = 0;
races = [];
addRace() {
var mainContainer = document.getElementById('mainContainer');
mainContainer.appendChild(document.createElement('br'));
var race = new raceClass(this.raceCount);
this.races.push(race);
this.raceCount++;
}
}
class raceClass {
runners = [];
count;
runnerCount = 0;
raceDiv = document.createElement('div');
raceNum = document.createElement('div');
startRaceButton = document.createElement('input');
addRunnerButton = document.createElement('input');
revRaceButton = document.createElement('input');
tableDiv = document.createElement('div');
tableNum = document.createElement('div');
startInterval;
startTime;
revStartTime;
reverseInterval;
constructor(number) {
// store the race no.
this.count = number;
// delcare the race div id
this.raceNum.id = 'raceNum' + this.count;
// delcare the table div id
this.tableNum.id = 'tableNum' + this.count;
// Add raceDiv to the race
document.getElementById('races').appendChild(this.raceDiv);
// Add tableDiv to the race
document.getElementById('tables').appendChild(this.tableDiv);
this.applyDivProperty();
this.initializeButtons();
}
applyDivProperty() {
// apply properties to the tableNum
this.tableNum.style.display = "inline-block";
// apply properties to the raceDiv
this.raceDiv.id = "Race" + this.count;
document.getElementById(this.raceDiv.id).classList.add("raceDivClass");
this.raceDiv.appendChild(this.raceNum);
document.getElementById(this.raceNum.id).innerHTML = '<p>Race: ' + this.count + '</p>';
// append the add race button
this.raceDiv.appendChild(this.addRunnerButton);
// apply properties to the tableDiv
this.tableDiv.id = "Table" + this.count;
document.getElementById(this.tableDiv.id).classList.add("tableClass");
this.tableDiv.appendChild(this.tableNum);
document.getElementById(this.tableNum.id).innerHTML = '<p>Table: ' + this.count + '</p>';
}
initializeButtons() {
// initialize add runner button
this.addRunnerButton.type = 'Button';
this.addRunnerButton.value = 'Add Runner';
this.addRunnerButton.id = 'AddRunner' + this.count;
this.addRunnerButton.onclick = this.addRunner.bind(this);
// initialize start race buttton
this.startRaceButton.type = 'Button';
this.startRaceButton.value = 'Start Race';
this.startRaceButton.id = "startRaceButton" + this.count;
this.startRaceButton.onclick = this.startRace.bind(this);
// initialize reverse race buttton
this.revRaceButton.type = 'Button';
this.revRaceButton.value = 'Reverse Race';
this.revRaceButton.id = "revRaceButton" + this.count;
this.revRaceButton.onclick = this.revRace.bind(this);
}
addRunner() {
var track = new Runner(this); //Initialize the runner object
this.runners.push(track); //Store the runner object in runners array of Race class
if (this.runnerCount > 0) {
// append the start race button
this.raceDiv.appendChild(this.startRaceButton);
}
this.runnerCount++;
}
startRace() {
this.startTime = Date.now();
this.startInterval = setInterval(() => {
this.runners.forEach(function(element) {
element.animate();
});
document.getElementById(this.startRaceButton.id).disabled = "true";
document.getElementById(this.addRunnerButton.id).disabled = "true";
}, 50);
}
stop() {
clearInterval(this.startInterval);
// append the start race button
this.raceDiv.appendChild(this.revRaceButton);
}
revRace() {
this.revStartTime = Date.now();
this.reverseInterval = setInterval(() => {
this.runners.forEach(function(element) {
element.animateReverse();
});
document.getElementById(this.revRaceButton.id).disabled = "true";
}, 50);
}
stopRev() {
clearInterval(this.reverseInterval);
}
}
class Runner {
count = 0;
parent;
track;
sprite;
timeTaken;
trackWidth;
element;
speed;
table;
printCount = 1;
stepCount = 1;
trackNum;
tbl;
lastStep;
constructor(race) {
// initialize the divs
this.parent = race;
this.track = document.createElement('div');
this.sprite = document.createElement('div');
this.table = document.createElement('table');
// assigns #id to table and track corresponding with parent div.
this.table.id = race.tableNum.id + '_Table_' + this.parent.runnerCount;
this.track.id = race.raceNum.id + '_Track_' + this.parent.runnerCount;
this.createUI();
this.timeTaken = ((Math.random() * 5) + 3);
this.speed = this.trackWidth / (this.timeTaken * 1000);
console.log(this.trackWidth, this.timeTaken);
console.log(this.timeTaken * 100);
}
createUI() {
this.count = this.parent.runnerCount;
this.createTable();
this.createTrack();
this.createSprite();
}
createTable() {
var parentDiv1 = document.getElementById(this.parent.tableNum.id);
parentDiv1.appendChild(this.table);
this.table.setAttribute = "border"
this.table.border = "1";
document.getElementById(this.table.id).classList.add("tableClass");
this.tbl = document.getElementById(this.table.id);
this.addRow("Track " + (this.count + 1), "");
this.addRow("Time", "Distance");
}
addCell(tr, val) {
var td = document.createElement('td');
td.innerHTML = val;
tr.appendChild(td)
}
addRow(val_1, val_2) {
var tr = document.createElement('tr');
this.addCell(tr, val_1);
this.addCell(tr, val_2);
this.tbl.appendChild(tr)
}
createTrack() {
var parentDiv = document.getElementById(this.parent.raceNum.id);
parentDiv.appendChild(this.track);
this.track.appendChild(this.sprite);
document.getElementById(this.track.id).classList.add("trackClass");
this.trackWidth = this.track.getBoundingClientRect().width;
}
createSprite() {
this.sprite.id = this.track.id + "_Runner";
document.getElementById(this.sprite.id).classList.add("spriteClass");
this.element = document.getElementById(this.sprite.id);
}
animate() {
// declare time variables
var timeNow = Date.now();
var timespent = timeNow - this.parent.startTime;
var diff = Math.floor(this.timeTaken * 100);
// step is position of sprite.
var step = timespent * this.speed;
// Print table for all tracks with 10 laps.
if ((Math.round(timespent / 50) * 50) == (Math.round(((diff - 25) * this.printCount) / 50) * 50)) {
this.addRow(this.printCount + ": " + timespent, (Math.floor(step)));
this.printCount++;
}
// check condition to stop
if (step > this.trackWidth - 23) {
document.getElementById(this.parent.raceNum.id).innerHTML += 'Winner: Runner' + (this.count + 1);
this.parent.stop();
}
this.element.style.left = step + 'px';
// ------------sprite animation----------------
// start position for the image slicer
var position = (3 - (Math.floor(step / 6.5) % 4)) * 25;
// we use the ES6 template literal to insert the variable "position"
this.element.style.backgroundPosition = `${position}px 0px`;
}
animateReverse() {
// declare time variables
var timeNow = Date.now();
var timespent = timeNow - this.parent.revStartTime;
var diff = Math.floor(this.timeTaken * 100);
console.log(this.count + " position of step " + this.element.style.left);
while (this.stepCount < 2) {
this.lastStep = parseFloat(this.element.style.left);
this.stepCount++;
}
console.log(this.count + " this is lastStep " + this.lastStep);
// step is position of sprite.
var step = this.lastStep - (this.speed * timespent);
// Print table for all tracks with 10 laps.
if ((Math.round(timespent / 50) * 50) == (Math.round(((diff - 25) * this.printCount) / 50) * 50)) {
this.addRow(this.printCount + ": " + timespent, (Math.floor(step)));
this.printCount++;
}
// check condition to stop
if (step < 25) {
document.getElementById(this.parent.raceNum.id).innerHTML += 'Winner: Runner' + (this.count + 1);
this.parent.stopRev();
}
this.element.style.left = step + 'px';
// ------------sprite animation----------------
// start position for the image slicer
//var position = (3 - (Math.floor(step / 6.5) % 4)) * 25;
//this.element.style.backgroundPosition = position + 'px 0px';
}
}
manager = new raceManager();
#tableContainer {
float: left;
}
#addRaces {
text-align: center;
}
.raceDivClass {
margin: 1% auto;
width: 60%;
text-align: center;
border: 1px solid;
}
.tableClass {
text-align: center;
border: 1px solid;
margin: 5px;
float: left;
}
.trackClass {
background-color: black;
height: 30px;
width: 98%;
margin: 1%;
position: relative;
}
.spriteClass {
background-image: url('data:image/png;base64,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');
position: absolute;
height: 30px;
width: 25px;
}
<!DOCTYPE html>
<html>
<head>
</head>
<body>
<div id="mainContainer">
<div id="addRaces">
<input type="Button" value="Add Race" onclick="manager.addRace()">
</div>
<div id="races">
</div>
<br>
</div>
<div id="tableContainer">
<div id="tables"></div>
</div>
</body>
</html>
I expect it to move from y to x after clicking the reverse button, but it is not moving.

When you run the reverse function the elements are no longer referencing the dom elements.
I am actually not sure why that is, maybe someone else can chime in.
Anyway, this will fix your problem:
Replace this.element.style.left = step + 'px';
With: document.getElementById(this.element.id).style.left = step + 'px';

Snake game - my snake leaves a trail on every move

I’m having trouble getting my snake to turn and not leave a trail. Every time my snake turns to go in a different direction it leaves behind pieces of itself. Each piece is a class of “hover” applied to a div block.
I created a function that I hoped would remove the excess pieces whenever a turn was made. My function removeExtra does remove the excess pieces on every turn (removeExtra is called from the moveSnake function each time an arrow is hit), but it also removes every piece of the snake when it turns. So every time I make a turn the snake starts over in that direction and then expands to its current size. A user could play and never run into any of the snake’s body pieces. If I don’t use this function though it leaves little snake turds all over the board!
Can someone help me fix my removeExtra function so that it only removes the class of hover that is not part of the snake body’s array? (var snake) In the removeExtra function I create an array of every hover class (every snake piece). I then use the length of this in the for loop. I have also tried using the difference between this array and the current snake array (var combo) as the second parameter of the for loop, but this doesn’t consistently clear the snake bits when I make turns.
I realize my code sucks. I’ve made this way more complicated than it should be. I should have used a canvas. But I’ve come this far, and I’m hoping there’s some way to salvage the game and never think about snakes again. If there really is no way to fix the mess I’ve made, just let me know, so that I can move on with my life. Thanks!
Here is the Codepen with the game.
Here is the function that's giving me trouble:
removeExtra = function(){
var array = [];
$(".hover").each(function() {
array.push($(this).attr("data"));
});
var len = array.length
var len2 = snake.length
var combo = len-len2
for (var i=0;i<len;i++){
$('*[data="' + array[i] + '"]').removeClass("hover");
}}
Since this is a work-in-progress (surprise!), just refresh the page if you don’t see any blue “food” pieces. Arrows keys will move the snake. You might have to click the board first.
//In the moveSnake function I had to use code from the below link in order to ignore multiple keydown events.
//https://stackoverflow.com/questions/9098901/how-to-disable-repetitive-keydown-in-jquery
$(document).ready(function() {
makebox();
addSnake();
moveSnake();
addBorder();
addFood();
killSnake();
addToSnake();
});
function makebox() {
var size = 30; //24
var boxSize = 20; //12
for (i = 1; i <= size * size; i++) {
$("#container").append("<div class='box'></div>");
};
$("#container").width(size * boxSize + "px");
$(".box").width(boxSize + "");
$(".box").height(boxSize + "px");
$(".box").each(function(i) {
$(this).attr('data', (i + 1));
});
};
function addBorder() {
//find all of the border divs and add a border class to them
$(".box").each(function() {
if ($(this).attr('data') % 25 == 0) {
$(this).addClass("right-border")
} else if ($(this).attr('data') % 25 == 1) {
$(this).addClass("left-border")
} else if ($(this).attr('data') < 25) {
$(this).addClass("top-border")
} else if ($(this).attr('data') >= 877) {
$(this).addClass("bottom-border")
}
})
}
function addSnake() {
var rightTime, leftTime, downTime, upTime;
moveRight = function() {
down = {}
rightTime = setInterval(function() {
for (var i = 0; i < snake.length; i++) {
snake[i]++
$('*[data="' + snake[i] + '"]').addClass("hover moving")
$('*[data="' + (snake[snake.length - 1] - snake.length) + '"]').removeClass("hover");
}
}, 150)
};
moveLeft = function() {
down = {}
leftTime = setInterval(function() { //snake -= 1
for (var i = 0; i < snake.length; i++) {
snake[i] -= 1
$('*[data="' + snake[i] + '"]').addClass("hover");
$('*[data="' + (snake[snake.length - 1] + snake.length) + '"]').removeClass("hover");
}
}, 150)
};
moveDown = function() {
down = {}
downTime = setInterval(function() { //snake += 25
for (var i = 0; i < snake.length; i++) {
snake[i] += 25
$('*[data="' + snake[i] + '"]').addClass("hover");
$('*[data="' + (snake[snake.length - 1] - 25 * snake.length) + '"]').removeClass("hover");
}
}, 150)
};
moveUp = function() {
down = {}
upTime = setInterval(function() { //snake -= 25
for (var i = 0; i < snake.length; i++) {
snake[i] -= 25
$('*[data="' + snake[i] + '"]').addClass("hover");
$('*[data="' + (snake[snake.length - 1] + 25 * snake.length) + '"]').removeClass("hover");
}
}, 150)
};
addTail = function() {
snake.push(snake[snake.length - 1])
}
var snake = [42]
$('*[data="' + snake[0] + '"]').addClass("hover");
var down = {};
removeExtra = function() {
var array = [];
$(".hover").each(function() {
array.unshift($(this).attr("data"));
});
var len = array.length
var len2 = snake.length
var combo = len - len2
for (var i = 0; i < len; i++) {
$('*[data="' + array[i] + '"]').removeClass("hover");
}
}
moveSnake = function() {
$(document).keydown(function(event) {
var keycode = (event.keyCode ? event.keyCode : event.which);
if (keycode == '39') {
if (down['39'] == null) {
window.clearInterval(leftTime);
window.clearInterval(downTime);
window.clearInterval(upTime);
moveRight();
removeExtra();
down['39'] = true;
}
} else if (keycode == '37') {
if (down['37'] == null) {
window.clearInterval(rightTime);
window.clearInterval(downTime);
window.clearInterval(upTime);
moveLeft();
removeExtra();
down['37'] = true;
}
} else if (keycode == '40') {
if (down['40'] == null) {
window.clearInterval(leftTime);
window.clearInterval(rightTime);
window.clearInterval(upTime);
moveDown();
removeExtra();
down['40'] = true;
}
} else if (keycode == '38') {
if (down['38'] == null) {
window.clearInterval(leftTime);
window.clearInterval(rightTime);
window.clearInterval(downTime);
moveUp();
removeExtra();
down['38'] = true;
}
}
});
addToSnake = function() {
var count = 0;
var config = {
attributes: true,
childList: true,
characterData: true
};
$(".box, .food").each(function() {
var target = this;
var observer = new MutationObserver(function(mutations) {
mutations.forEach(function(mutation) {
if ($(".food").hasClass("hover") == true) {
$(".box").removeClass("food")
addTail();
addFood();
}
});
});
observer.observe(target, config);
});
}
killSnake = function() {
var config = {
attributes: true,
childList: true,
characterData: true,
subtree: true
};
$(".right-border, .left-border, .top-border, .bottom-border").each(function() {
var target = this;
var observer = new MutationObserver(function(mutations) {
mutations.forEach(function(mutation) {
console.log("Game over!")
});
});
observer.observe(target, config);
});
}
}
addFood = function() {
var random = Math.floor(Math.random() * (900 - 1 + 1)) + 1;
$('*[data="' + random + '"]').addClass("food")
};
};
.box {
display: inline-block;
border: 2px grey solid;
}
#container {
display: block;
border: 2px black solid;
border-radius: 5px;
font-size: 0;
margin: 10px auto;
}
.hover {
background-color: black;
}
.food {
background-color: blue;
}
.white {
background-color: white;
}
.right-border,
.left-border,
.top-border,
.bottom-border {
background: red;
border: 2px red solid;
}
<!DOCTYPE html>
<html lang="en">
<head>
<title>Snake</title>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css">
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.1.1/jquery.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js"></script>
<link rel="stylesheet" href="style.css">
<script type="text/javascript" src="script.js"></script>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.0/jquery.min.js"></script>
</head>
<body>
<div class="container">
<center>
<h1>Snake</h1>
<div id="container"></div>
</center>
</div>
</body>
</html>

hsl to rgb conversion. Values waaaay off. Compare to solution. What am I doing differently?

SOLVED! see EDITs
I built a color picker app. Very simple; you click on the rgb color palette, and it creates a swatch with RGB values, HSL values, and HEX values.
I used this formula for the conversions.
Basically, I built my HSL values from the x and y mouse positions with a static 99% saturation.
From there, I created the color palette to pick from by converting HSL to RGB.
A click event on the palette will create RGB, HSL, and HEX swatches along with the values for each.
Since I can't get the RGB and HSL values to match I haven't incorporated the HEX values yet.
I finally found a working solution. Can someone tell me where my calculations drift away from the working solution? I don't just want to accept the working solution and move on; I want to know where my logic starts to break down.
Thanks so much for any help!
EDIT: So Bob__ suggested I use a better way to normalize my RGB values instead of just adding or subtracting 1 depending on their values. I added this function to make the RGB channels based on the hue value(-0.333 - 360.333)
function normalizeRGB(color){
var newVal = (360.333 - (-0.333))/(360.333 - (-0.333)) *
(color- (-0.333) + (-0.333));
return newVal;
}
index.html:
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Color Picker, Bro</title>
<link href='http://fonts.googleapis.com/css? family=Raleway:700,300' rel='stylesheet' type='text/css'>
<link rel="stylesheet" href="style.css">
<script src='https://code.jquery.com/jquery-2.1.3.min.js'></script>
<script type="text/javascript" src='myColorPickerSol.js'></script>
<!-- <script type="text/javascript" src='actualWorkingColorPickerSol.js'></script> -->
</head>
<body>
<div id='container'>
<h1>Color Picker, bro</h1>
<section id='canvas'></section>
<section id='readout'>
<p>HSL: <span id='hsl'></span></p>
<section id='swatchhsl'></section>
<p>RGB: <span id='rgb'></span></p>
<section id='swatchrgb'></section>
<p>HEX: <span id='hex'></span></p>
</section>
</section>
</div>
</body>
</html>
style.css:
body {
background: url(http://subtlepatterns.com/patterns/subtle_white_mini_waves.png);
}
#container {
margin: 0 auto;
width: 800px;
height: inherit;
text-align: center;
font-family: Raleway;
font-weight: 300;
}
#canvas {
margin: 0 auto;
border: 5px solid black;
box-sizing: border-box;
height: 360px;
width: 360px;
}
#readout {
background: rgba(117,117,117, .2);
margin: 20px auto;
height: 400px;
width: 360px;
border: 1px #333 solid;
box-sizing: border-box;
border-radius: 20px;
}
#swatchhsl,#swatchrgb {
margin: 0 auto;
height: 75px;
width: 95%;
border-radius: 20px;
}
p, span {
letter-spacing: 1px;
}
p {
font-weight: 700;
}
span {
font-weight: 300;
}
myColorPickerSol.js
$(document).ready(function(){
var canvas = $('#canvas');
//swatch matches closest when either pure blue, green or red; loses all accuracy when colors mix.
// dark blue gets really close. Purple gets really close, which makes me suspect the Green channel value is where the problem lies.
// y-axis as Luminace(0-100%)
// x-axis as Hue(0-360)
var yPos;
var lum;
var hue;// aka xPos;
var temp1;//for hslToRGB
var temp2;//for hslToRGB
var tempR;
var tempG;
var tempB;
var red;
var blue;
var green;
var realColVal;
$('#canvas').mousemove(function(event){
hue = Math.abs(event.offsetX);
hueForRGB = (hue/360);
yPos = Math.abs(event.offsetY);
lum = (yPos/360);
// console.log(lum + ' lum');
$(canvas).css({'background-color':'hsl('+ event.offsetX + ',99%,'+ Math.round(lum *100) + '%)'});
});
// swatch listener
$(canvas).click(function(event){
hsl2RGB(lum);
$('#rgb').text(red + ','+ green + ',' + blue);
$('#hsl').text(hue + ',99%,' + Math.round(lum * 100) + '%');
$(canvas).css({'background-color':'rgb('+ red + ','+ green + ','+ blue + ')'});
});
//red channel must be in upper third; green in middle third; blue in lower third.
function hsl2RGB(lum){
tempR = (hueForRGB + 0.333);
tempG = hueForRGB;
tempB = (hueForRGB - 0.333);
// set temporary lum based on whether it is above/below 50%
temp1 = lumMorOrLess50(lum);
// set secondary temporary lum value
temp2 = ((2.0 * (lum)) - temp1);
//-----------EDIT -----------------------------
// used the formula to make the tempR|G|B values between 0 and 1
// tempR = makeRGB01(tempR);
// tempG = makeRGB01(tempG);
// tempB = makeRGB01(tempB);
//-----------------------------------------------
red = Math.round(convert2RGB(tempR,temp1,temp2));
green = Math.round(convert2RGB(tempG,temp1,temp2));
blue = Math.round(convert2RGB(tempB,temp1,temp2));
//swatch appears on click for hsl and rgb
$('#swatchhsl').css({'background-color':'hsl('+ hue + ',99%,'+ Math.round(lum * 100 )+ '%)'});
$('#swatchrgb').css({'background-color':'rgb('+ red + ','+ green + ','+ blue + ')'});
};
//force tempR|G|B to be between 0-1
function makeRGB01(input) {
if(input > 1){
input -= 1.0;
} else if(input < 0){
input += 1.0;
};
return input;
};
//get value for each rgb channel
function convert2RGB(tempColVal, val1, val2){
//first convert tempColVal to between 0 and 1 then make it an RGB value
tempColVal = makeRGB01(tempColVal);
//next run 3 test;
if(6.0 * tempColVal < 1){
realColVal = (val2 + (val1 - val2) * 6 * tempColVal);
console.log(realColVal + 'test 1; val1: '+ val1 + 'val2: ' + val2 );
//-------EDIT ------------------------------------------
// test2 will set realColVal to val1 instead of tempColVal
//-------------------------------------------------------
} else if(2.0 * tempColVal < 1){
realColVal = val1;
console.log(realColVal + 'test 2');
} else if(3.0 * tempColVal < 2){
realColVal = (val2 + (val1 - val2)*(0.666 - tempColVal) * 6.0);
console.log(realColVal + 'test 3');
} else {
realColVal = val2;
console.log(realColVal + 'realColVal = default (temp 2)');
};
//-------EDIT ------------------------------------------
// normalize value before multiplying by 255
realColVal = normalizeRGB(realColVal);
//-------------------------------------------------------
// force value between 0 and 1 then set it to RGB scale and
// return
return (Math.abs(realColVal) * 255.0));
};
//configure temporary luminance value, temp1, based on luminance
function lumMorOrLess50(val){
if(val < 0.50){
return ((1.0 + 0.99) * val);
} else {
return ((.99 + val) - (val * .99));
};
};
});
This is the working solution, actualColorPickerSol.js What did I do differently?
$(function() {
console.log('Loaded, bro');
colorPicker();
});
function colorPicker() {
var canvas = $('#canvas');
canvas.on('mousemove', changeCanvasBackground);
canvas.on('click', printColorReadout);
}
function changeCanvasBackground(event) {
var xCoord = Math.abs(event.offsetX);
var yCoord = Math.abs(event.offsetY);
var rgbValues = 'rgb(' + rgb(hsl(xCoord, yCoord)) + ')';
$(this).css('background', rgbValues);
}
function printColorReadout(event) {
var xCoord = event.offsetX;
var yCoord = event.offsetY;
var hslValues = hsl(xCoord, yCoord);
var rgbValues = rgb(hslValues);
var hexValues = hex(rgbValues);
var hslString = parseHSL(hslValues);
var rgbString = parseRGB(rgbValues);
var hexString = parseHEX(hexValues);
$('#hsl').text(hslString);
$('#rgb').text(rgbString);
$('#hex').text(hexString);
$('#swatchhsl').css('background', hslString);
$('#swatchrgb').css('background', rgbString);
}
function hsl(xCoord, yCoord) {
// HSL = hsl(hue, saturation, luminance)
var hsl;
var hue = xCoord;
var luminance = Math.round(((yCoord / 360) * 100));
return [hue, 100, luminance];
}
function rgb(hslValues) {
var hue = hslValues[0];
var sat = hslValues[1] / 100;
var lum = hslValues[2] / 100;
var tempLum1, tempLum2, tempHue, tempR, tempG, tempB;
if (lum < .50) {
tempLum1 = lum * (1 + sat);
} else {
tempLum1 = (lum + sat) - (lum * sat);
}
tempLum2 = (2 * lum) - tempLum1;
tempHue = hue / 360;
tempR = tempHue + .333;
tempG = tempHue;
tempB = tempHue - .333;
//This is the only part I think I did differently.
//The code below makes sure the green and blue values
//are between 0 and 1, then it checks all the colors to
//make sure they are between 0 and 1. I tried this,
// and there was no change in the effect;
// the hsl and rgb values were still different.
if (tempG < 0) { tempG += 1};
if (tempG > 1) { tempG -= 1};
if (tempB < 0) { tempB += 1};
if (tempB > 1) { tempB -= 1};
var normalizedRGB = [tempR, tempG, tempB].map(function(color, idx) {
if (color < 0) { return color += 1};
if (color > 1) { return color -= 1};
return color;
});
var rgbArray = normalizedRGB.map(function(color) {
if (colorCondition1(color)) {
return tempLum2 + ( tempLum1 - tempLum2 ) * 6 * color;
} else if (colorCondition2(color)) {
return tempLum1;
} else if (colorCondition3(color)) {
return tempLum2 + (tempLum1 - tempLum2) * (.666 - color) * 6;
} else {
return tempLum2;
}
});
var rgbValues = rgbArray.map(function(color, idx) {
var convertedVal = color * 255;
return Math.round(convertedVal);
});
return rgbValues;
}
function hex(rgbValues) {
var r = rgbValues[0];
var g = rgbValues[1];
var b = rgbValues[2];
return [numToHex(r), numToHex(g), numToHex(b)];
}
function numToHex(num) {
var hexCode = num.toString(16);
if (hexCode.length < 2) { hexCode = "0" + hexCode; }
return hexCode;
}
function colorCondition1(val) {
return 6 * val < 1;
}
function colorCondition2(val) {
return 2 * val < 1;
}
function colorCondition3(val) {
return 3 * val < 2;
}
function parseHSL(hslValues) {
return [
"hsl(",
hslValues[0], ", ",
hslValues[1], "%, ",
hslValues[2], "%)"
].join('');
}
function parseRGB(rgbValues) {
return "rgb(" + rgbValues.join(', ') + ")";
}
function parseHEX(hexValues) {
return "#" + hexValues.join('');
}

Comparing your functions to the algorythm presented in the link you posted, I think that a more correct implementation of convert2RGB, as I told in my comments, may be:
function convert2RGB(tempColVal, val1, val2){
//first convert tempColVal to between 0 and 1 then make it an RGB value
tempColVal = makeRGB01(tempColVal);
//next run 3 test;
if(6.0 * tempColVal < 1){
realColVal = (val2 + (val1 - val2) * 6.0 * tempColVal);
// console.log(realColVal + 'test 1; val1: '+ val1 + 'val2: ' + val2 );
} else if(2.0 * tempColVal < 1){
realColVal = val1;
// console.log(realColVal + 'test 2');
} else if(3.0 * tempColVal < 2){
realColVal = (val2 + (val1 - val2)*(0.666 - tempColVal) * 6.0);
// console.log(realColVal + 'test 3');
} else {
realColVal = val2;
// console.log(realColVal + 'realColVal = default (temp 2)');
};
// Convert them to 8-bit by multiply them with 255 and return
return Math.round(realColVal * 255.0);
};
Edit:
Don't change your makeRGB01(), in that algorythm is used in the same way you did before calling convert2RGB(). Your mistake is applying that to returned corrected value too.