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JavaScript Css Animation

I have a Javascript animation at http://dev17.edreamz3.com/css/
All code works, however, there are performance problems. on Desktop, its good, On mobile things are so slow that it's unusable. I want to optimize the animation so that it runs smoothly on mobile. It can take 20 seconds or more for the animation to render.
Right now the way the code is designed is in js/anim.js there is a render() function that gets executed every time a scroll event happens. The problem is that this routine is not efficient, that's what I think of. Each time render() executes it loops through all the paths and sections of the maze and redraws them, is there any alternative way or a strategy to get it working both on mobile as well as desktop.
var offPathTime = 1000;
window.offSection = -1;
function render() {
// var top = ($window.scrollTop() + (0.4 * $window.height())) / window.scale;
var top = ($('.parent-div').scrollTop() + (0.4 * $('.parent-div').height())) / window.scale;
top -= 660;
top /= mazeSize.h;
if (window.offSection != -1) {
$body.addClass("blockScroll");
$('.parent-div').addClass("blockScroll");
// var wtop = $window.scrollTop() / window.scale;
var wtop = $('.parent-div').scrollTop() / window.scale;
wtop -= 660;
wtop /= mazeSize.h;
var $offSection = $("#offSection" + window.offSection);
var $section = $("#section" + window.offSection);
$(".section").removeClass("sectionActive");
$offSection.addClass("sectionActive");
$section.addClass("sectionActive");
var sTop = 200 -(mazeSize.h * (window.offSections[window.offSection].cy - wtop));
$container.animate({
left: 290 -(mazeSize.w * window.offSections[window.offSection].cx) + "px",
top: sTop + "px"
}, offPathTime);
// Path
var lr = offPaths[window.offSection].x1 > offPaths[window.offSection].x0;
var dx = Math.abs(offPaths[window.offSection].x1 - offPaths[window.offSection].x0);
var dashw = (dx * mazeSize.w) | 0;
$offPaths[window.offSection].css("width", "0px");
$offPaths[window.offSection].show();
if (lr) {
$offPaths[window.offSection].animate({
width: dashw + "px"
}, offPathTime);
} else {
var x0 = offPaths[window.offSection].x0 * mazeSize.w;
var x1 = offPaths[window.offSection].x1 * mazeSize.w;
$offPaths[window.offSection].css("left", x0 + "px");
$offPaths[window.offSection].animate({
width: dashw + "px",
left: x1 + "px"
}, offPathTime);
}
return;
}
$body.removeClass("blockScroll");
$('.parent-div').removeClass("blockScroll");
$(".offPath").hide();
if ($container.css("top") != "0px") {
$container.animate({
left: "-1550px",
top: "0px"
}, 500);
}
var pathIdx = -1;
var path0 = paths[0];
var path1;
var inPath = 0;
var i;
var curTop = 0;
var found = false;
for (i=0; i<paths.length; i++) {
var top0 = (i == 0) ? 0 : paths[i-1].y;
var top1 = paths[i].y;
if (top >= top0 && top < top1) {
pathIdx = i;
path1 = paths[i];
inPath = (top - top0) / (top1 - top0);
found = true;
if (i > 0) {
var dy = paths[i].y - paths[i-1].y;
var dx = paths[i].x - paths[i-1].x;
var vert = dx == 0;
if (vert)
$paths[i-1].css("height", (dy * mazeSize.h * inPath) + "px");
$paths[i-1].show();
}
} else if (top >= top0) {
path0 = paths[i];
var dy = paths[i].y - top0;
var vert = dy != 0;
if (i > 0) {
if (vert)
$paths[i-1].css("height", (dy * mazeSize.h) + "px");
$paths[i-1].show();
}
} else {
if (i > 0) {
$paths[i-1].hide();
}
}
curTop = top1;
}
// Check for an active section
$(".section").removeClass("sectionActive");
var section;
for (i=0; i<sections.length; i++) {
var d = Math.abs(sections[i].cy - (top - 0.05));
if (d < 0.07) {
var $section = $("#section" + i);
$section.addClass("sectionActive");
}
}
}

1) At the very least - assign all DOM objects to variables outside of the function scope. Like this:
var $parentDiv = $('.parent-div');
var $sections = $(".section");
...
function render() {
...
2) Also you should probably stop animation before executing it again, like this:
$container.stop(true).animate({
...
If you are running render() function on scroll - it will run many times per second. stop() helps to prevent it somewhat.
3) If it will not be sufficient - you can switch from jQuery to Zepto(jQuery-like api, but much faster and uses css transitions for animations) or to Velocity(basically drop-in replacement for jQuery $.animate and much faster than original) or even to GSAP - much more work obviously, but it is very fast and featured animation library.

jQuery - animate moving elements with no overlapping

I'm trying to make my menu items move to random positions without overlapping on top of each other. I'm using animate with top left and obviously for those to work I set the position property to absolute.
Now the problem with this approach is that they will go across on top of each other when I just want them to bounce off on each other.
Is there a way to accomplish this?
function Menu($item) {
this.item = $item;
};
Menu.prototype.makeNewPosition = function ($container) {
var h = $container.height() - 50;
var w = $container.width() - 50;
var nh = Math.floor(Math.random() * h);
var nw = Math.floor(Math.random() * w);
return [nh, nw];
};
Menu.prototype.move = function () {
var that = this;
$.each(this.item, function(index, value) {
var newq = that.makeNewPosition($(value).parent());
$(value).animate({
top: newq[0],
left: newq[1]
}, 2000, function() {
that.move();
});
});
};
var $menu = new Menu($('.nav li'));
$menu.move();
JSfiddle

Random clickable div move around a webpage

I have this javascript code that make the div randomly move around web page,but i am not understanding how to make it that it does not flow continuously,its like if user click then it move and then stops there and whenever it clicks again it moves to another random position and after 5 time it shows a message and disappears.I am not getting how to make this animation not like a flow but like a leaf falling from a tree.
here is the jsfiddle : JSFIDDLE
below is the javascript code :
$(document).ready(function(){
animateDiv();
});
function makeNewPosition(){
// Get viewport dimensions (remove the dimension of the div)
var h = $(window).height() - 50;
var w = $(window).width() - 50;
var nh = Math.floor(Math.random() * h);
var nw = Math.floor(Math.random() * w);
return [nh,nw];
}
function animateDiv(){
var newq = makeNewPosition();
var oldq = $('.a').offset();
var speed = calcSpeed([oldq.top, oldq.left], newq);
$('.a').animate({ top: newq[0], left: newq[1] }, speed, function(){
animateDiv();
});
};
function calcSpeed(prev, next) {
var x = Math.abs(prev[1] - next[1]);
var y = Math.abs(prev[0] - next[0]);
var greatest = x > y ? x : y;
var speedModifier = 0.1;
var speed = Math.ceil(greatest/speedModifier);
return speed;
}

I would use the CSS3 transitions, they hare hardware accelerated that mean smoother animations:
$(document).ready(function(){
var counter = 0;
$('.a').click( function () {
if ( ++counter < 5 ) {
var pos = makeNewPosition();
this.style.left = pos[1] +'px';
this.style.top = pos[0] +'px';
}
else if ( counter = 5 ) {
this.style.display = 'none';
alert( 'Your message' );
}
});
});
function makeNewPosition(){
// Get viewport dimensions (remove the dimension of the div)
var h = $(window).height() - 50;
var w = $(window).width() - 50;
var nh = Math.floor(Math.random() * h);
var nw = Math.floor(Math.random() * w);
return [nh,nw];
}
div.a {
width : 50px;
height: 50px;
background-color: red;
position: fixed;
left : 0px;
top : 0px;
-webkit-transition: left 2s, top 2s;
-moz-transition: left 2s, top 2s;
-o-transition: left 2s, top 2s;
transition: left 2s, top 2s;
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<div class='a'></div>

The animateDiv function calls itself at the end, so as soon as it reaches its destination it picks a new destination and goes there. Here it is with the recursive callback removed:
function animateDiv(){
var newq = makeNewPosition();
var oldq = $('.a').offset();
var speed = calcSpeed([oldq.top, oldq.left], newq);
$('.a').animate({ top: newq[0], left: newq[1] }, speed);
};
And an updated fiddle, which now requires clicking the box to animate it: http://jsfiddle.net/Xw29r/3975/

Something like this ?
var isStart = true;
$(".a").click(function () {
animateDiv(isStart);
});
function makeNewPosition() {
// Get viewport dimensions (remove the dimension of the div)
var h = $(window).height() - 50;
var w = $(window).width() - 50;
var nh = Math.floor(Math.random() * h);
var nw = Math.floor(Math.random() * w);
return [nh, nw];
}
function animateDiv() {
var newq = makeNewPosition();
var oldq = $('.a').offset();
var speed = calcSpeed([oldq.top, oldq.left], newq);
if (isStart) {
$('.a').animate({
top: newq[0],
left: newq[1]
}, speed, function () {
animateDiv();
});
isStart = false;
} else {
$('.a').stop();
isStart = true;
}
};
function calcSpeed(prev, next) {
var x = Math.abs(prev[1] - next[1]);
var y = Math.abs(prev[0] - next[0]);
var greatest = x > y ? x : y;
var speedModifier = 0.1;
var speed = Math.ceil(greatest / speedModifier);
return speed;
}
div.a {
width: 50px;
height:50px;
background-color:red;
position:fixed;
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.7.2/jquery.min.js"></script>
<div class='a'></div>

select specific area of a div

I made a carousel using 2 divs named "left" and "right" putting mousemove events on them. I wanted to make it go up and down as well so I created a "top" and "bottom" and noticed that I couldn't make them combine to go the way the cursor goes.
I thus thought of targeting a specific area in the container (i.e top half of my container div) instead of creating divs inside triggering a specific direction, this way (I think) I can trigger all these event altogether. However after now hours of research I couldn't find a way to do so.
How should I proceed ? here is the code : http://jsfiddle.net/pool4/vL5g3/3/
var x=0,
y=0,
rateX=0,
rateY=0,
maxspeed=10;
var backdrop = $('.backdrop');
$('.directionx', backdrop).mousemove(function(e){
var $this = $(this);
var left = $this.is('.left');
var right = $this.is('.right');
if (left){
var w = $this.width();
rateX = (w - e.pageX - $this.offset().left + 1)/w;
}
else if (right){
var w = $this.width();
rateX = -(e.pageX - $this.offset().left + 1)/w;
}
});
$('.directiony', backdrop).mousemove(function(e){
var $this = $(this);
var top = $this.is('.top');
var bottom = $this.is('.bottom');
if (top){
var h = $this.height();
rateY = (h - e.pageY - $this.offset().top + 1)/h;
}
else if (bottom) {
var h = $this.height();
rateY = -(e.pageY - $this.offset().top + 1)/h;
}
});
backdrop.hover(
function(){
var scroller = setInterval( moveBackdrop, 30 );
$(this).data('scroller', scroller);
},
function(){
var scroller = $(this).data('scroller');
clearInterval( scroller );
}
);
function moveBackdrop(){
x += maxspeed * rateX;
y += maxspeed * rateY;
var newpos = x+'px '+y+'px';
backdrop.css('background-position',newpos);
}

Your problem is that the divs that control movement up and down are placed over the ones that control left and right, so the latter do not receive the mousemove event ever. Mouse events do not propagate through layers, even if they're transparent. I changed your code and CSS, so each div is in one of the corners. To make things easier, I've used data-* attributes so the direction controlled by each div is set in a declarative way, without the need to change the code. You'll see that the code is much simpler (and it could be simplified even more).
By the way, you could achieve this witout extra divs, just controlling where the cursor is (to the top, right, left or bottom of the center of the div).
backdrop.on('mousemove', '.dir', function(e){
var $this = $(this);
var direction = $(e.target).attr('data-direction');
var left = direction.indexOf('left') > - 1;
var right = direction.indexOf('right') > - 1;
var top = direction.indexOf('up') > - 1;
var bottom = direction.indexOf('down') > - 1;
if (left){
var w = $this.width();
rateX = (w - e.pageX - $this.offset().left + 1)/w;
}
else if (right){
var w = $this.width();
rateX = -(e.pageX - $this.offset().left + 1)/w;
}
if (top){
var h = $this.height();
rateY = (h - e.pageY - $this.offset().top + 1)/h;
}
else if (bottom) {
var h = $this.height();
rateY = -(e.pageY - $this.offset().top + 1)/h;
}
});
I've updated your fiddle.
EDIT In this new fiddle I do it without extra divs:
var w = backdrop.width() / 2;
var h = backdrop.height() / 2;
var center = {
x: backdrop.offset().left + backdrop.width() / 2,
y: backdrop.offset().top + backdrop.height() / 2
};
backdrop.on('mousemove', function(e){
var offsetX = e.pageX - center.x;
var offsetY = e.pageY - center.y;
rateX = -offsetX / w;
rateY = -offsetY / h;
});
backdrop.hover(
function(){
var scroller = $(this).data('scroller');
if (!scroller) {
scroller = setInterval( moveBackdrop, 30 );
$(this).data('scroller', scroller);
}
},
function(){
var scroller = $(this).data('scroller');
if (scroller) {
clearInterval( scroller );
$(this).data('scroller', null);
}
}
);
As you see, the mousmove handler is considerably simpler.

To avoid issue of children losing event could use just the one.
First HTML from 4 child divs to just one
<div class="backdrop">
<div class="direction"></div>
</div>
<div id="pos"></div>
Next Inside the mousemove find your relative position
//Get Relative Position
var relX = e.pageX - $this.offset().left;
var relY = e.pageY - $this.offset().top;
Get Relative Position as a percentage of width and put 50% of it in negative for direction
var w = $this.width();
rateX = ((relX / w) - 0.5) * -1;
var h = $this.height();
rateY = ((relY / h) - 0.5) * -1;
Fiddle

Javascript Circle slider degrees to time

I am looking at this slider http://jsfiddle.net/sCanr/1/.
(function () {
var $container = $('#container');
var $slider = $('#slider');
var sliderW2 = $slider.width()/2;
var sliderH2 = $slider.height()/2;
var radius = 200;
var deg = 0;
var elP = $('#container').offset();
var elPos = { x: elP.left, y: elP.top};
var X = 0, Y = 0;
var mdown = false;
$('#container')
.mousedown(function (e) { mdown = true; })
.mouseup(function (e) { mdown = false; })
.mousemove(function (e) {
if (mdown) {
var mPos = {x: e.clientX-elPos.x, y: e.clientY-elPos.y};
var atan = Math.atan2(mPos.x-radius, mPos.y-radius);
deg = -atan/(Math.PI/180) + 180; // final (0-360 positive) degrees from mouse position
X = Math.round(radius* Math.sin(deg*Math.PI/180));
Y = Math.round(radius* -Math.cos(deg*Math.PI/180));
$slider.css({ left: X+radius-sliderW2, top: Y+radius-sliderH2 });
// AND FINALLY apply exact degrees to ball rotation
$slider.css({ WebkitTransform: 'rotate(' + deg + 'deg)'});
$slider.css({ '-moz-transform': 'rotate(' + deg + 'deg)'});
//
// PRINT DEGREES
$('#test').html('angle deg= '+deg);
}
});
})();
What i want to do it turn this into a time line control for a html5 video. However, i am having some trouble with calculating the math behind this.

Try this:
http://jsfiddle.net/phdphil/Zv4K7/#base
It works by keeping global variables for the current position and last angle (you should change this setup to construct a specific dial with its own state). Each movement then calculates the delta (modulo 360, which requires a proper modulus function) and assumes that movements of < 180 degrees are forward movements, and > 180 degrees (remember -1 modulo 360 is 359) are negative movements. This then updates the cumulative total position:
var current = 0;
var lastAngle = 0;
// ... inside the handler
var delta = 0;
var dir = 0;
var rawDelta = mod(deg-lastAngle,360.0);
if(rawDelta < 180) {
dir = 1;
delta = rawDelta;
} else {
dir = -1;
delta = rawDelta-360.0;
}
current += delta;
lastAngle = deg;
$('#test').html('angle deg= '+current); // current instead of deg
Just for clarity, the dir variable holds the direction of this movement, which could be used to update a >> or << indicator onscreen.
The real modulus function, taken from this SO answer:
function mod(x,n) {
return ((x%n)+n)%n;
}