Smooth movement with background mousemove script - javascript

I found out how to make a background image move with mouse movement.
I'm trying to figure out how to smooth the movement out or make it more fluid.
The most I've figured out is that by dividing by larger and larger numbers there is less background movement, but that's as far as I've gotten.
html
<body id="body">
</body>
css
html {
width: 100%;
}
body {
background-image: url("http://sherly.mobile9.com/download/media/656/49_ybQFKMAV.png");
background-repeat: no-repeat;
background-size: cover;
height:4400px;
}
jquery
$(document).ready(function(){
$('#body').css('background-position', 'calc(45% - 0px)');
$('#body').mousemove(function(e){
var x = -(e.pageX + this.offsetLeft) / 205;
var y = -(e.pageY + this.offsetTop) / 100;
$(this).css('background-position', "calc( 45% - " + x + 'px' + ")" + y + 'px');
});
});
A good example would be from flickr after zooming in on an image.
Or this guy's site: http://ericportfolio.com/

You should separate out the background into an element of its own.
Style the element with:
.background
{
will-change: transform;
}
To prime the rending engine to promote it to its own compositing layer. This makes transform changes more cheap.
Animate transform via translateX(...) translateY(...) instead of background position.
To smooth movement you can keep track of the last several position changes and average them.
Example with 10 sample smoothing:
const root = document.querySelector(".root");
const bg = document.querySelector(".background");
const positions = [];
root.addEventListener("mousemove", e => {
const x = -(e.pageX + bg.offsetLeft) / 50;
const y = -(e.pageY + bg.offsetTop) / 50;
positions.push({ x, y });
const averageCount = 10;
if (positions.length > averageCount)
positions.splice(0, 1);
const current = positions.reduce((acc, e) => { acc.x += e.x; acc.y += e.y; return acc }, { x: 0, y: 0 });
current.x /= positions.length;
current.y /= positions.length;
bg.style.transform = `translateX(${current.x}px) translateY(${current.y}px)`;
});
.root
{
position: relative;
}
.background
{
will-change: transform;
width: 100%;
height: 100%;
}
.overlay
{
position: absolute;
left: 50%;
top: 50%;
transform: translateX(-50%) translateY(-50%);
}
<div class="root">
<img class="background" src="https://i.stack.imgur.com/35oj3.png"/>
<h1 class="overlay">Lorem Ipsum</h1>
</div>

Related

How can I effectively pan an entire image programmatically?

I have a 11500x11500 div that consists of 400 images, that obviously overflows the viewport.
I would like to pan around the whole div programmatically.
I want to generate an animation and by the time the animation is over, the whole of the div must have been panned across the viewport, top to bottom, left to right.
Right now, I am "splitting" my 11500x1500 div into tiles. The maximum width and height of each tile is the width and height of the viewport.
I store the coordinates of each tile and then I randomly choose one, pan it left-to-right and then move on to the next one.
I would like to know:
whether my method is correct or whether I am missing something in my calculations/approach and it could be improved. Given the size, it is hard for me to tell whether I'm actually panning the whole of the div after all
whether I can make the panning effect feel more "organic"/"natural". In order to be sure that the whole div is eventually panned, I pick each tile and pan it left-to-right, move on to the next one etc. This feels kind of rigid and too formalised. Is there a way to pan at let's say an angle or with a movement that is even more random and yet be sure that the whole div will eventually be panned ?
Thank in advance for any help.
This is the jsfiddle and this is the code (for the sake of the example/test every "image" is actually a div containing its index as text):
function forMs(time) {
return new Promise((resolve) => {
setTimeout(() => {
resolve()
}, time)
})
}
let container = document.getElementById('container')
let {
width,
height
} = container.getBoundingClientRect()
let minLeft = window.innerWidth - width
let minTop = window.innerHeight - height
let i = 0
while (i < 400) {
// adding "image" to the container
let image = document.createElement('div')
// add some text to the "image"
// to know what we're looking at while panning
image.innerHTML = ''
let j = 0
while (j < 100) {
image.innerHTML += ` ${i + 1}`
j++
}
container.appendChild(image)
i++
}
let coords = []
let x = 0
while (x < width) {
let y = 0
while (y < height) {
coords.push({
x,
y
})
y += window.innerHeight
}
x += window.innerWidth
}
async function pan() {
if (!coords.length) {
return;
}
let randomIdx = Math.floor(Math.random() * coords.length)
let [randomCoord] = coords.splice(randomIdx, 1);
console.log(coords.length)
container.classList.add('fast')
// update style in new thread so new transition-duration is applied
await forMs(10)
// move to new yet-unpanned area
container.style.top = Math.max(-randomCoord.y, minTop) + 'px'
container.style.left = Math.max(-randomCoord.x, minLeft) + 'px'
// wait (approx.) for transition to end
await forMs(2500)
container.classList.remove('fast')
// update style in new thread so new transition-duration is applied
await forMs(10)
//pan that area
let newLeft = -(randomCoord.x + window.innerWidth)
if (newLeft < minLeft) {
newLeft = minLeft
}
container.style.left = newLeft + 'px'
// wait (approx.) for transition to end
await forMs(4500)
// move on to next random area
await pan()
}
pan()
html,
body {
position: relative;
width: 100%;
height: 100%;
margin: 0;
padding: 0;
overflow: auto;
}
* {
margin: 0;
padding: 0;
}
#container {
position: absolute;
top: 0;
left: 0;
text-align: left;
width: 11500px;
height: 11500px;
transition: all 4s ease-in-out;
transition-property: top left;
font-size: 0;
}
#container.fast {
transition-duration: 2s;
}
#container div {
display: inline-block;
height: 575px;
width: 575px;
border: 1px solid black;
box-sizing: border-box;
font-size: 45px;
overflow: hidden;
word-break: break-all;
}
<div id="container"></div>
I think following improvements can be made:
Hide overflow on html and body so user can not move scrollbar and disturb the flow.
Calculate minLeft and minTop every time to account for window resizing. You might need ResizeObserver to recalculate things.
Increase transition times to avoid Cybersickness. In worse case RNG will pick bottom right tile first so your container will move the longest in 2seconds! Maybe, you can zoom-out and move then zoom-in then perform pan. Or use any serpentine path which will make shorter jumps.
Performance improvements:
Use transform instead of top, left for animation.
Use will-change: transform;. will-change will let browser know what to optimize.
Use translate3D() instead of translate(). ref
Use requestAnimationFrame. Avoid setTimeout, setInterval.
This is an old but good article: https://www.paulirish.com/2012/why-moving-elements-with-translate-is-better-than-posabs-topleft/
Modified code to use transform:
function forMs(time) {
return new Promise((resolve) => {
setTimeout(() => {
resolve()
}, time)
})
}
let container = document.getElementById('container')
let stat = document.getElementById('stats');
let {
width,
height
} = container.getBoundingClientRect()
let minLeft = window.innerWidth - width
let minTop = window.innerHeight - height
let i = 0
while (i < 400) {
// adding "image" to the container
let image = document.createElement('div')
// add some text to the "image"
// to know what we're looking at while panning
image.innerHTML = ''
let j = 0
while (j < 100) {
image.innerHTML += ` ${i + 1}`
j++
}
container.appendChild(image)
i++
}
let coords = []
let x = 0
while (x < width) {
let y = 0
while (y < height) {
coords.push({
x,
y
})
y += window.innerHeight
}
x += window.innerWidth
}
let count = 0;
async function pan() {
if (!coords.length) {
stat.innerText = 'iteration: ' +
(++count) + '\n tile# ' + randomIdx + ' done!!';
stat.style.backgroundColor = 'red';
return;
}
let minLeft = window.innerWidth - width
let minTop = window.innerHeight - height
let randomIdx = Math.floor(Math.random() * coords.length);
randomIdx = 1; //remove after debugging
let [randomCoord] = coords.splice(randomIdx, 1);
stat.innerText = 'iteration: ' +
(++count) + '\n tile# ' + randomIdx;
console.log(coords.length + ' - ' + randomIdx)
container.classList.add('fast')
// update style in new thread so new transition-duration is applied
await forMs(10)
// move to new yet-unpanned area
let yy = Math.max(-randomCoord.y, minTop);
let xx = Math.max(-randomCoord.x, minLeft);
move(xx, yy);
// wait (approx.) for transition to end
await forMs(2500)
container.classList.remove('fast')
// update style in new thread so new transition-duration is applied
await forMs(10)
//pan that area
let newLeft = -(randomCoord.x + window.innerWidth)
if (newLeft < minLeft) {
newLeft = minLeft
}
xx = newLeft;
//container.style.left = newLeft + 'px'
move(xx, yy);
// wait (approx.) for transition to end
await forMs(4500)
// move on to next random area
await pan()
}
pan()
function move(xx, yy) {
container.style.transform = "translate3D(" + xx + "px," + yy + "px,0px)";
}
html,
body {
position: relative;
width: 100%;
height: 100%;
margin: 0;
padding: 0;
overflow: hidden;
}
* {
margin: 0;
padding: 0;
box-sizing: border-box;
}
#container {
text-align: left;
width: 11500px;
height: 11500px;
transition: all 4s ease-in-out;
transition-property: transform;
font-size: 0;
will-change: transform;
}
#container.fast {
transition-duration: 2s;
}
#container div {
display: inline-block;
height: 575px;
width: 575px;
border: 1px solid black;
box-sizing: border-box;
font-size: 45px;
overflow: hidden;
word-break: break-all;
}
#stats {
border: 2px solid green;
width: 100px;
background-color: lightgreen;
position: fixed;
opacity: 1;
top: 0;
left: 0;
z-index: 10;
}
<div id=stats>iteration: 1 tile# 11</div>
<div id="container"></div>
Note I haven't implemented everything in above snippet.

I want to use my equation to scale a div I can't figure out how to use it as a variable

I have this for my js and it returns a modified version of the distance between my element and my cursor... I want to use it to scale a separate element, any ideas as to how I would do that?
var elm = document.getElementById("qrcode");
elm.addEventListener("mousemove",getcordd , false)
function getcordd(ev){
var bdns = ev.target.getBoundingClientRect();
var y = ev.clientY - bdns.left;
var x = ev.clientX - bdns.top;
var d = Math.sqrt(x*x+y*y);
var s = (d*0.1)
console.log (`${s}`);
}
This is my CSS
.cursor {
position: absolute;
width: 250px;
height: 250px;
top: -50%;
left: -50%;
margin: -125px 0 0 -125px;
border-radius: 50%;
background-color: white;
transition: transform 0.8s ease-out;
mix-blend-mode: difference;
filter: grayscale(2);
pointer-events: none;
}
.cursor.is-moving {
transform: scale (var(`${s}`));
}
This is my HTML:
<div class="cursor"></div>
<main>
<h1>Find the QR code for the spotify playlist</h1>
<div id="qrcode">
<img id="QRCode" src="img/qr-code.png" alt="">
</div>
</main>
I basically made a custom curser that I would like to scale as I get closer to the element which is a QRCode
The goal would be to make it so the .cursor class scales up to 1 as it gets closer to the #qrcode. And gets smaller as it goes further away. I would like it to be relative to the window...
I am still very new to coding so I am not sure about how to do it and I have not found any information on the internet
If I correctly understand, you could do it like this
Keep in mind, that elm.addEventListener("mousemove"... would trigger function only if your cursor is already moves over elm (#qrcode), because you attach event listener to elm, not to whole window.
var elm = document.getElementById("qrcode");
var cursor = document.querySelector('.cursor');
elm.addEventListener("mousemove", function(ev) {
var distance = getcordd(ev);
cursor.style=`transform: scale(${s})`;
}, false);
function getcordd(ev) {
var bdns = ev.target.getBoundingClientRect();
var y = ev.clientY - bdns.left;
var x = ev.clientX - bdns.top;
var d = Math.sqrt(x * x - y * y);
var s = d * 0.1;
return s;
}

CSS JQuery Rotate image inside container

I am trying to rotate an image inside a container.
The container width must have a limit, and so should the height.
I was able to accomplish it with the following code, but there is an issue with one of the images.
When image 2 is rotated sideways, or 45 degrees, it jumps outside of the borders.
It works fine for the other images.
What am I doing wrong?
var degrees = 0;
function x () {
var setRotator = (function () {
var setRotation,
setScale,
offsetAngle,
originalHeight,
originalFactor;
setRotation = function (degrees, scale, element) {
element.style.webkitTransform = 'rotate(' + degrees + 'deg) scale(' + scale + ')';
element.style.transform = 'rotate(' + degrees + 'deg) scale(' + scale + ')';
};
getScale = function (degrees) {
var radians = degrees * Math.PI / 180,
sum;
if (degrees < 90) {
sum = radians - offsetAngle;
} else if (degrees < 180) {
sum = radians + offsetAngle;
} else if (degrees < 270) {
sum = radians - offsetAngle;
} else {
sum = radians + offsetAngle;
}
return (originalHeight / Math.cos(sum)) / originalFactor;
};
return function (inner) {
offsetAngle = Math.atan(inner.offsetWidth / inner.offsetHeight);
originalHeight = inner.offsetHeight;
originalFactor = Math.sqrt(Math.pow(inner.offsetHeight, 2) + Math.pow(inner.offsetWidth, 2));
return {
rotate: function (degrees) {
setRotation (degrees, getScale(degrees), inner);
}
}
};
}());
var //outer = document.getElementById('outer'),
inner = document.getElementById('testImg'),
rotator = setRotator(testImg);
degrees += 45;
if (degrees >= 360) {
degrees = 0;
}
rotator.rotate(degrees);
}
$('#btn1').click(function(){
x()
});
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<button onclick=document.getElementById('testImg').src='https://dev.w3.org/SVG/tools/svgweb/samples/svg-files/smile.svg'>Img1</button>
<button onclick=document.getElementById('testImg').src='https://dev.w3.org/SVG/tools/svgweb/samples/svg-files/juanmontoya_lingerie.svg'>Img2</button>
<button onclick=document.getElementById('testImg').src='https://dev.w3.org/SVG/tools/svgweb/samples/svg-files/php.svg'>Img3</button>
<button type="button" id="btn1" >Rotate Div</button>
<DIV id="container" style=" width:60%;">
<DIV id="outer" width="100%" style=" position: relative;border-style:dotted;">
<img id ="testImg" src="https://dev.w3.org/SVG/tools/svgweb/samples/svg-files/smile.svg" style="width:100%;height:100%;border-style:dotted;border-color:red;">
</DIV>
</DIV>
You'll need to position the image absolutely within the div and edit the scale so that it's positive and never greater than 1. I have a working version here: https://jsfiddle.net/e9h30w1z/
I've added this CSS
img {
max-width: 100%;
max-height: 100%;
height: auto;
width: auto;
position: absolute;
object-fit: contain;
left: 50%;
transform: translate(-50%);
}
#outer {
height: 0;
padding-bottom: 100%;
}
I edited the CSS rule being added within the setRotation method to include translate(-50%) (this is part of the image positioning)
And I changed the return statement of the getScale method to the following:
scale = (originalHeight / Math.cos(sum)) / originalFactor;
return (Math.abs(scale) > 1) ? 1 : Math.abs(scale);
As a note, negative scale flips the image which is why one of my attempts started skipping positions.

How to make custom follow cursor follow Y axis scroll

I'm using a bit of HTML & CSS on my squarespace site to create a custom follow cursor. I want to just have a floaty circle with no actual cursor displayed. I've gotten it to mostly work, but when my site scrolls the follow cursor doesn't move with the page scroll and just gets stuck at the top.
And that just caused the follow cursor to stop moving with mouse movement entirely, becoming static on the center of the page.
Injecting HTML & CSS on to squarespace site to create a custom follow cursor:
body {
background: #161616;
}
.wrap {
position: absolute;
top: 0;
left: 0;
bottom: 0;
right: 0;
overflow: hidden;
}
#ball {
width: 60px;
height: 60px;
background: none;
border: 1px solid grey;
border-radius: 50%;
position: absolute;
left: 50%;
top: 50%;
margin: -10px 0 0 -10px;
pointer-events: none;
}
<body onload="followMouse();">
<div class="wrap">
<div id="ball"></div>
</div>
<script type="text/javascript">
var $ = document.querySelector.bind(document);
var $on = document.addEventListener.bind(document);
var xmouse, ymouse;
$on('mousemove', function (e) {
xmouse = e.clientX || e.pageX;
ymouse = e.clientY || e.pageY;
});
var ball = $('#ball');
var x = void 0,
y = void 0,
dx = void 0,
dy = void 0,
tx = 0,
ty = 0,
key = -1;
var followMouse = function followMouse() {
key = requestAnimationFrame(followMouse);
if(!x || !y) {
x = xmouse;
y = ymouse;
} else {
dx = (xmouse - x) * 0.125;
dy = (ymouse - y) * 0.125;
if(Math.abs(dx) + Math.abs(dy) < 0.1) {
x = xmouse;
y = ymouse;
} else {
x += dx;
y += dy;
}
}
ball.style.left = x + 'px';
ball.style.top = y + 'px';
};
</script>
</body>
[EDIT] Great job on updating your question, the demo and the problem are very clear now. Don't worry about your demo not scrolling, I just added a bunch of divs with some height in my demo to simulate that. Here's everything you need to / should change to make it all work:
var followMouse = function followMouse() ... is very strange syntax and I'm not sure what the exact outcome will be.
Either declare the function normally function followMouse() ..., or store it in a variable using either the:
function definition var followMouse = function() ... or
arrow definition var followMouse = () => ...
To simply get it all working you just need to adjust for the current scroll amount of either the document or in my demo's case the element with class ".wrap".
This can be done using the scrollTop member of the object returned by your $() function.
I started by just adding $(".wrap").scrollTop to the ymouse variable in the mousemove listener, but while this works it needs you to move the mouse for the circle to realize it's scrolled off the page.
So instead we just add $(".wrap").scrollTop to the css that is being set to the ball in the last lines of followMouse.
I changed the overflow property from hidden to scroll since that's kind of where the problem is occuring ;)
I've also added cursor: none to your .wrap css so that you get the desired effect of no cursor but your custom one.
var $ = document.querySelector.bind(document);
var $on = document.addEventListener.bind(document);
var followMouse = function() {
key = requestAnimationFrame(followMouse);
if (!x || !y) {
x = xmouse;
y = ymouse;
} else {
dx = (xmouse - x) * 0.125;
dy = (ymouse - y) * 0.125;
if (Math.abs(dx) + Math.abs(dy) < 0.1) {
x = xmouse;
y = ymouse;
} else {
x += dx;
y += dy;
}
}
ball.style.left = x + 'px';
ball.style.top = $(".wrap").scrollTop + y + 'px';
};
var xmouse, ymouse;
var ball = $('#ball');
var x = void 0,
y = void 0,
dx = void 0,
dy = void 0,
tx = 0,
ty = 0,
key = -1;
$on('mousemove', function(e) {
xmouse = e.clientX || e.pageX;
ymouse = e.clientY || e.pageY;
});
body {
background: #161616;
}
.wrap {
position: absolute;
top: 0;
left: 0;
bottom: 0;
right: 0;
overflow: scroll;
cursor: none;
}
#ball {
width: 60px;
height: 60px;
background: none;
border: 1px solid grey;
border-radius: 50%;
position: absolute;
left: 50%;
top: 50%;
margin: -10px 0 0 -10px;
pointer-events: none;
}
.makeOverflow {
width: 100px;
height: 300px;
}
<body onload="followMouse();">
<div class="wrap">
<div id="ball"></div>
<div class="makeOverflow"> </div>
<div class="makeOverflow"> </div>
<div class="makeOverflow"> </div>
<div class="makeOverflow"> </div>
</div>
</body>
This will probably be fixed by changing the #ball CSS from being absolutely positioned to a fixed position, then it should scroll down the page with your original js

2D Infinitely looping Array of elements

The Goal :
The idea is to create an element grid (image gallery for exemple) that would infinitely loop on itself scrolling on two axes.
There should be no holes nor too much randomness (avoid having the same element randomly falling aside from itself). And this no matter how many element there is in the first place (it seems easy to infinite loop through a grid of 16 (4*4) elements, not that much over 17 (17*1). (My guess is that any prime number of elements is by definition a pain to make a grid of).
So I actually found a wonderful working exemple :
http://www.benstockley.com/
It's actually really close (probably better) than what I was imagining. Now it's using canvas and i tried looking at the javascript and it's a 30000 minified lines long script so I really can't read any core logic behind it.
Math side / Problem solving :
This is the logic and theory behind the problem, the math involved and the mindset.
How the program should process the list of elements so we have no holes, infinite grid, best repartion of the elements over all the axes.
My guess is that it somehow has to be procedural. I'm not sure if we should create grids or loop through the list on every axes (kind of like sudoku ? i don't know);
Pratical side / UI / UX :
Any advice on the technologies involved, pieces of code. I'm guessing it classic DOM is out of the way and that somehow canvas or 2D webgl will be mandatory. But I would love to hear any advice on this side.
Besides all the elements grid processing. The UI and UX involved in exploring a 2D infinite or vast layout in DOM or renderer is somehow not classical. The best technologies or advice on doing this are welcome.
Exemples :
I would welcome any working exemple that somewhat share an aspect of this problem.
I've got a fiddle that's set up to arrange your 2d grid.
It functions by using horizontal and vertical "step sizes". So, moving one step right in the grid advances the horizontal step size in the list. Moving one step down advances the vertical step size in the list (and they accumulate).
We allow the advances in the list to loop back to zero when the end is reached.
It likely makes sense to use a horizontal step size of 1 (so a row of your grid will maintain your list order). For the vertical step size, you want an integer that shares no common divisors with the list length. Though it's no guarantee, I used the (rounded) square root of the list length as something that will work in lots of cases.
I'll reproduce the fiddle here:
var list = ['red','green','blue','cyan','orange','yellow','pink'];
var hstep = 1;
var vstep = Math.ceil(Math.sqrt(list.length));
function getListItem(x,y) {
var index = x * hstep + y * vstep;
return list[index % list.length];
}
var elementSize = 30;
var gutterSize = 10;
function getOffset(x,y) {
return [10 + (elementSize + gutterSize) * x, 10 + (elementSize + gutterSize) * y];
}
var frame = $('.frame');
function drawElement(x,y) {
var listItem = getListItem(x,y);
var offsets = getOffset(x,y);
var element = $('<div></div>').addClass('element').css({
left: offsets[0] + 'px',
top: offsets[1] + 'px',
'background-color': listItem
});
frame.append(element);
}
function drawElements() {
var x = 0, y = 0;
while (10 + (elementSize + gutterSize) * x < frame.width()) {
while (10 + (elementSize + gutterSize) * y < frame.height()) {
drawElement(x,y);
y++;
}
y = 0;
x++;
}
}
drawElements();
.frame {
border: 2px solid black;
margin: 40px auto;
height: 300px;
width: 300px;
position: relative;
overflow: hidden;
}
.frame .element {
position: absolute;
width: 30px;
height: 30px;
}
.buttons {
position: absolute;
top: 0px;
width: 100%;
}
.buttons button {
position: absolute;
width: 30px;
height: 30px;
padding: 5px;
}
button.up {top: 0px; left: 46%;}
button.down {top: 355px; left: 46%;}
button.left {top: 160px; left: 15px;}
button.right {top: 160px; right: 15px;}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div class="frame">
</div>
<div class="buttons">
<button class="up">↑</button>
<button class="down">↓</button>
<button class="left">←</button>
<button class="right">→</button>
</div>
You can see I've left some simple buttons to implement movement, but they are not functional yet. If you wanted to continue implementation along the lines of what I've done here, you could render your elements to a certain range beyond the visible frame, then implement some sort of animated repositioning. The renderElements function here only renders what is visible, so you can use something like that and not get stuck in rendering infinite elements, even though there's no theoretical limit to how far you can "scroll".
#arbuthnott I edited your code to implement the exploration via decrementing relativeX and relativeY variables. Also I inserted an "origin" div (1x1 px, overflow visible). This DOM element will represent the X and Y origin. I'm not sure it's essential but it's really convenient.
Now my function currently remove all elements and reinsert all elements on each update (every 500ms for now).
The idear would be to find a way to compare which elements I need versus which one already exists.
Maybe storing existing elements into an array, and compare the array with the "query" array. Than see just the elements that are missing.
This is the idear, not sure about the implementation (I suck at handling arrays).
https://jsfiddle.net/bnv6mumd/64/
var sources = ['red','green','blue','cyan','orange','yellow','pink','purple'];
var frame = $('.frame'),
origin = $('.origin');
var fWidth = 600,
fHeight = 300,
srcTotal = sources.length,
srcSquare = Math.ceil(Math.sqrt(srcTotal)),
rX = 0,
rY = 0;
var gridSize = 30,
gutterSize = 5,
elementSize = gridSize - gutterSize;
function getSourceItem(x,y) {
var index = x + y * srcSquare;
return sources[Math.abs(index) % srcTotal];
}
function getOffset(x,y) {
return [gridSize * x,gridSize * y];
}
function drawElement(x,y) {
var sourceItem = getSourceItem(x,y);
var offsets = getOffset(x,y);
var element = $('<div></div>').addClass('element').css({
left: offsets[0] + 'px',
top: offsets[1] + 'px',
'background-color': sourceItem,
});
origin.append(element);
}
function init() {
var x = 0, y = 0;
while ( gridSize * x < fWidth) {
while ( gridSize * y < fHeight) {
drawElement(x,y);
y++;
}
y = 0;
x++;
}
}
function updateElements() {
origin.empty();
var x = -Math.trunc(rX / gridSize) -1, y = - Math.trunc(rY / gridSize) -1;
while ( gridSize * x + rX < fWidth) {
while ( gridSize * y + rY < fHeight) {
drawElement(x,y);
y++;
}
y = -Math.ceil(rY / gridSize);
x++;
}
}
function animate() {
rX -= 5;
rY -= 5;
origin.css({left: rX, top: rY})
updateElements();
console.log("relative X : " + rX + " | relative Y : " + rY);
}
setInterval(animate, 500)
init();
.frame {
border: 2px solid black;
margin: 40px auto;
height: 300px;
width: 600px;
position: relative;
overflow: hidden;
}
.origin {
height: 1px;
width: 1px;
position: absolute;
overflow: visible;
}
.frame .element {
position: absolute;
width: 25px;
height: 25px;
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div class="frame">
<div class="origin" style="top:0;left:0;"></div>
</div>
This is my final snippet version (i will start to work on real implementation specific to my case now).
I think I optimized in a decent way DOM operations, code structure etc (I am very well open to suggestions though).
I now only update the elements that needs to be updated (click near the frame to show overflow)
https://jsfiddle.net/bnv6mumd/81/
var sources = ['red', 'green', 'blue', 'cyan', 'orange', 'yellow', 'pink', 'purple'];
var frame = $('.frame'),
origin = $('.origin');
var srcTotal = sources.length,
srcSquare = Math.round(Math.sqrt(srcTotal)),
fWidth = 200,
fHeight = 200,
cellSize = 50,
gutterSize = 20,
gridSize = [Math.floor(fWidth / cellSize) + 1, Math.floor(fHeight / cellSize) + 1],
aX = 0, // Absolute/Applied Coordinates
aY = 0,
rX = 0, // Relative/frame Coordinates
rY = 0;
function getSrcItem(x, y) {
var index = x + y * srcSquare;
return sources[Math.abs(index) % srcTotal];
}
function getOffset(x, y) {
return [cellSize * x, cellSize * y];
}
function getY() {
return Math.floor(-rY / cellSize);
}
function getX() {
return Math.floor(-rX / cellSize);
}
function drawElement(x, y) {
var srcItem = getSrcItem(x, y),
offsets = getOffset(x, y),
element = $('<div></div>').addClass('element').css({
left: offsets[0] + 'px',
top: offsets[1] + 'px',
'background-color': srcItem,
}).attr({
"X": x,
"Y": y
});
origin.append(element);
}
function drawCol(x, y) {
var maxY = y + gridSize[1];
while (y <= maxY + 1) {
drawElement(x - 1, y - 1);
y++;
}
}
function drawLign(x, y) {
var maxX = x + gridSize[0];
while (x <= maxX + 1) {
drawElement(x - 1, y - 1);
x++;
}
}
function drawGrid() {
origin.empty();
var x = getX(),
y = getY(),
maxX = x + gridSize[0],
maxY = y + gridSize[1];
while (y <= maxY + 1) {
drawLign(x, y);
x = getX();
y++;
}
}
function updateX(x, y, diffX, diffY) {
if (Math.sign(diffX) == -1) {
drawCol(aX - 1, y);
$('[x=' + (aX + gridSize[0]) + ']').remove();
aX--;
} else if (Math.sign(diffY) == 1) {
drawCol(aX + gridSize[0] + 2, y);
$('[x=' + (aX - 1) + ']').remove();
aX++;
}
}
function updateY(x, y, diffX, diffY) {
if (Math.sign(diffY) == -1) {
drawLign(x, aY - 1);
$('[y=' + (aY + gridSize[0]) + ']').remove();
aY--;
} else if (Math.sign(diffY) == 1) {
drawLign(x, aY + gridSize[0] + 2);
$('[y=' + (aY - 1) + ']').remove();
aY++;
}
}
function animate() {
rX += 1;
rY += 1;
origin.css({
left: rX,
top: rY
});
var x = getX(),
y = getY(),
diffX = x - aX,
diffY = y - aY;
if (diffX) {
updateX(x, y, diffX, diffY)
};
if (diffY) {
updateY(x, y, diffX, diffY)
};
requestAnimationFrame(animate);
}
$('body').click(function() {
$(frame).toggleClass("overflow");
})
drawGrid();
animate();
.frame {
border: 2px solid black;
margin: 100px auto;
height: 200px;
width: 200px;
position: relative;
}
.overflow{
overflow:hidden;
}
.origin {
height: 1px;
width: 1px;
position: absolute;
overflow: visible;
}
.frame .element {
position: absolute;
width: 30px;
height: 30px;
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div class="frame overflow">
<div class="origin" style="top:0;left:0;"></div>
</div>

Categories