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Random movement of circles created by the script

I have a function that craeates divs with a circle.
Now they are all created and appear at the beginning of the page and go further in order.
Next, I need each circle to appear in a random place. I did this.
Now I need all of them to move randomly across the entire page, I have difficulties with this.
Here is an example of how everything works for one element that is already on the page.
https://jsfiddle.net/quej8wko/
But when I add this code, all my created circles don't move.
I get an error:
"message": "Uncaught TypeError: Cannot set properties of null (setting 'willChange')",
This is probably due to the fact that initially there are no circles on the page. How can I connect the code so that all created circles move?
//creating circles
var widthHeight = 40; // <-- circle width
var margin = 20; // <-- margin - is it necessary ?
var delta = widthHeight + margin;
function createDiv(id, color) {
let div = document.createElement('div');
var currentTop = 0;
var documentHeight = document.documentElement.clientHeight;
var documentWidth = document.documentElement.clientWidth;
div.setAttribute('class', id);
if (color === undefined) {
let colors = ['#35def2', '#35f242', '#b2f235', '#f2ad35', '#f24735', '#3554f2', '#8535f2', '#eb35f2', '#f2359b', '#f23547'];
div.style.backgroundColor = colors[Math.floor(Math.random() * colors.length)];
}
else {
div.style.backgroundColor = color;
}
div.classList.add("circle");
div.classList.add("animation");
// Get the random positions minus the delta
currentTop = Math.floor(Math.random() * documentHeight) - delta;
currentLeft = Math.floor(Math.random() * documentWidth) - delta;
// Keep the positions between -20px and the current positions
var limitedTop = Math.max(margin * -1, currentTop);
var limitedLeft = Math.max(margin * -1, currentLeft);
div.style.top = limitedTop + "px";
div.style.left = limitedLeft + "px";
document.body.appendChild(div);
}
let i = 0;
const oneSecond = 1000;
setInterval(() => {
i += 1;
createDiv(`circle${i}`)
}, oneSecond);
//move circles
function RandomObjectMover(obj, container) {
this.$object = obj;
this.$container = container;
this.container_is_window = container === window;
this.pixels_per_second = 250;
this.current_position = { x: 0, y: 0 };
this.is_running = false;
}
// Set the speed of movement in Pixels per Second.
RandomObjectMover.prototype.setSpeed = function(pxPerSec) {
this.pixels_per_second = pxPerSec;
}
RandomObjectMover.prototype._getContainerDimensions = function() {
if (this.$container === window) {
return { 'height' : this.$container.innerHeight, 'width' : this.$container.innerWidth };
} else {
return { 'height' : this.$container.clientHeight, 'width' : this.$container.clientWidth };
}
}
RandomObjectMover.prototype._generateNewPosition = function() {
// Get container dimensions minus div size
var containerSize = this._getContainerDimensions();
var availableHeight = containerSize.height - this.$object.clientHeight;
var availableWidth = containerSize.width - this.$object.clientHeight;
// Pick a random place in the space
var y = Math.floor(Math.random() * availableHeight);
var x = Math.floor(Math.random() * availableWidth);
return { x: x, y: y };
}
RandomObjectMover.prototype._calcDelta = function(a, b) {
var dx = a.x - b.x;
var dy = a.y - b.y;
var dist = Math.sqrt( dx*dx + dy*dy );
return dist;
}
RandomObjectMover.prototype._moveOnce = function() {
// Pick a new spot on the page
var next = this._generateNewPosition();
// How far do we have to move?
var delta = this._calcDelta(this.current_position, next);
// Speed of this transition, rounded to 2DP
var speed = Math.round((delta / this.pixels_per_second) * 100) / 100;
//console.log(this.current_position, next, delta, speed);
this.$object.style.transition='transform '+speed+'s linear';
this.$object.style.transform='translate3d('+next.x+'px, '+next.y+'px, 0)';
// Save this new position ready for the next call.
this.current_position = next;
};
RandomObjectMover.prototype.start = function() {
if (this.is_running) {
return;
}
// Make sure our object has the right css set
this.$object.willChange = 'transform';
this.$object.pointerEvents = 'auto';
this.boundEvent = this._moveOnce.bind(this)
// Bind callback to keep things moving
this.$object.addEventListener('transitionend', this.boundEvent);
// Start it moving
this._moveOnce();
this.is_running = true;
}
RandomObjectMover.prototype.stop = function() {
if (!this.is_running) {
return;
}
this.$object.removeEventListener('transitionend', this.boundEvent);
this.is_running = false;
}
// Init it
var x = new RandomObjectMover(document.querySelector(".circle"), window);
// Start it off
x.start();
.circle {
clip-path: circle(50%);
height: 40px;
width: 40px;
margin: 20px;
position: absolute;
}

I have modified the snippet which works as you expected.
There was a mistake where you were initializing and creating the object instance only once and none of the div elements that you created inside the setInterval function never got Instantiated.
I think you are just starting out with JavaScript with this sample project.
Below are few suggestions:
Learn to debug the code. You should be using dev tools by making use of debugger statement where it takes you to the source code to analyze the variable scope and stack during the runtime. console.log also helps in few situations.
I could see a lot of confusing naming convention (You have named the create div parameter as id but creating a div class using that id)
Try using ES6 features (class syntax is really good when writing OOP in JS although it's just a syntactic sugar for prototype)
//creating circles
var widthHeight = 40; // <-- circle width
var margin = 20; // <-- margin - is it necessary ?
var delta = widthHeight + margin;
function createAndInitializeDivObject(id, color) {
let div = document.createElement('div');
var currentTop = 0;
var documentHeight = document.documentElement.clientHeight;
var documentWidth = document.documentElement.clientWidth;
div.setAttribute('class', id);
if (color === undefined) {
let colors = ['#35def2', '#35f242', '#b2f235', '#f2ad35', '#f24735', '#3554f2', '#8535f2', '#eb35f2', '#f2359b', '#f23547'];
div.style.backgroundColor = colors[Math.floor(Math.random() * colors.length)];
}
else {
div.style.backgroundColor = color;
}
div.classList.add("circle");
div.classList.add("animation");
// Get the random positions minus the delta
currentTop = Math.floor(Math.random() * documentHeight) - delta;
currentLeft = Math.floor(Math.random() * documentWidth) - delta;
// Keep the positions between -20px and the current positions
var limitedTop = Math.max(margin * -1, currentTop);
var limitedLeft = Math.max(margin * -1, currentLeft);
div.style.top = limitedTop + "px";
div.style.left = limitedLeft + "px";
document.body.appendChild(div);
var x = new RandomObjectMover(document.querySelector(`.${id}`), window);
x.start();
}
let i = 0;
const oneSecond = 1000;
setInterval(() => {
i += 1;
createAndInitializeDivObject(`circle${i}`)
}, oneSecond);
//move circles
function RandomObjectMover(obj, container) {
this.$object = obj;
this.$container = container;
this.container_is_window = container === window;
this.pixels_per_second = 250;
this.current_position = { x: 0, y: 0 };
this.is_running = false;
}
// Set the speed of movement in Pixels per Second.
RandomObjectMover.prototype.setSpeed = function(pxPerSec) {
this.pixels_per_second = pxPerSec;
}
RandomObjectMover.prototype._getContainerDimensions = function() {
if (this.$container === window) {
return { 'height' : this.$container.innerHeight, 'width' : this.$container.innerWidth };
} else {
return { 'height' : this.$container.clientHeight, 'width' : this.$container.clientWidth };
}
}
RandomObjectMover.prototype._generateNewPosition = function() {
// Get container dimensions minus div size
var containerSize = this._getContainerDimensions();
var availableHeight = containerSize.height - this.$object.clientHeight;
var availableWidth = containerSize.width - this.$object.clientHeight;
// Pick a random place in the space
var y = Math.floor(Math.random() * availableHeight);
var x = Math.floor(Math.random() * availableWidth);
return { x: x, y: y };
}
RandomObjectMover.prototype._calcDelta = function(a, b) {
var dx = a.x - b.x;
var dy = a.y - b.y;
var dist = Math.sqrt( dx*dx + dy*dy );
return dist;
}
RandomObjectMover.prototype._moveOnce = function() {
// Pick a new spot on the page
var next = this._generateNewPosition();
// How far do we have to move?
var delta = this._calcDelta(this.current_position, next);
// Speed of this transition, rounded to 2DP
var speed = Math.round((delta / this.pixels_per_second) * 100) / 100;
//console.log(this.current_position, next, delta, speed);
this.$object.style.transition='transform '+speed+'s linear';
this.$object.style.transform='translate3d('+next.x+'px, '+next.y+'px, 0)';
// Save this new position ready for the next call.
this.current_position = next;
};
RandomObjectMover.prototype.start = function() {
if (this.is_running) {
return;
}
// Make sure our object has the right css set
this.$object.willChange = 'transform';
this.$object.pointerEvents = 'auto';
this.boundEvent = this._moveOnce.bind(this)
// Bind callback to keep things moving
this.$object.addEventListener('transitionend', this.boundEvent);
// Start it moving
this._moveOnce();
this.is_running = true;
}
RandomObjectMover.prototype.stop = function() {
if (!this.is_running) {
return;
}
this.$object.removeEventListener('transitionend', this.boundEvent);
this.is_running = false;
}
// Init it
var x = new RandomObjectMover(document.querySelector(".circle"), window);
// Start it off
x.start();
.circle {
width: 35px;
height: 35px;
border-radius: 35px;
background-color: #ffffff;
border: 3px solid purple;
position: absolute;
}
<!DOCTYPE html>
<html>
<head>
<link rel="stylesheet" href="style.css">
</head>
<body>
<div class="circle"></div>
<script src="app.js"></script>
</body>
</html>

Transforming img - white dots appear on chronium

I am trying to get 3d transform effect of the bacground image on mouse move.
I have checked f.e. jquery.plate tilt.js and many others plugins, BUT, each of them has problem on chronium browsers like Chrome or Opera (it works fine even on IE11 -.-)
See the attachment and please adwise what is that and if it is fixable? The "dots" appear on mouse move (when background moves) randomly but in line within image.
(function($) {
'use strict';
var namespace = 'jquery-plate';
function Plate($element, options) {
this.config(options);
this.$container = $element;
if (this.options.element) {
if (typeof this.options.element === 'string') {
this.$element = this.$container.find(this.options.element);
} else {
this.$element = $(this.options.element);
}
} else {
this.$element = $element;
}
this.originalTransform = this.$element.css('transform');
this.$container
.on('mouseenter.' + namespace, this.onMouseEnter.bind(this))
.on('mouseleave.' + namespace, this.onMouseLeave.bind(this))
.on('mousemove.' + namespace, this.onMouseMove.bind(this));
}
Plate.prototype.config = function(options) {
this.options = $.extend({
inverse: false,
perspective: 500,
maxRotation: 10,
animationDuration: 200
}, this.options, options);
};
Plate.prototype.destroy = function() {
this.$element.css('transform', this.originalTransform);
this.$container.off('.' + namespace);
};
Plate.prototype.update = function(offsetX, offsetY, duration) {
var rotateX;
var rotateY;
if (offsetX || offsetX === 0) {
var height = this.$container.outerHeight();
var py = (offsetY - height / 2) / (height / 2);
rotateX = this.round(this.options.maxRotation * -py);
} else {
rotateY = 0;
}
if (offsetY || offsetY === 0) {
var width = this.$container.outerWidth();
var px = (offsetX - width / 2) / (width / 2);
rotateY = this.round(this.options.maxRotation * px);
} else {
rotateX = 0;
}
if (this.options.inverse) {
rotateX *= -1;
rotateY *= -1;
}
if (duration) {
this.animate(rotateX, rotateY, duration);
} else if (this.animation && this.animation.remaining) {
this.animation.targetX = rotateX;
this.animation.targetY = rotateY;
} else {
this.transform(rotateX, rotateY);
}
};
Plate.prototype.reset = function(duration) {
this.update(null, null, duration);
};
Plate.prototype.transform = function(rotateX, rotateY) {
this.currentX = rotateX;
this.currentY = rotateY;
this.$element.css('transform',
(this.originalTransform && this.originalTransform !== 'none' ? this.originalTransform + ' ' : '') +
'perspective(' + this.options.perspective + 'px) ' +
'rotateX(' + rotateX + 'deg) rotateY(' + rotateY + 'deg)'
);
};
Plate.prototype.animate = function(rotateX, rotateY, duration) {
if (duration) {
this.animation = this.animation || {};
var remaining = this.animation.remaining;
this.animation.time = performance.now();
this.animation.remaining = duration || null;
this.animation.targetX = rotateX;
this.animation.targetY = rotateY;
if (!remaining) {
requestAnimationFrame(this.onAnimationFrame.bind(this));
}
} else {
this.transform(rotateX, rotateY);
}
};
Plate.prototype.round = function(number) {
return Math.round(number * 1000) / 1000;
};
Plate.prototype.offsetCoords = function(event) {
var offset = this.$container.offset();
return {
x: event.pageX - offset.left,
y: event.pageY - offset.top
};
};
Plate.prototype.onAnimationFrame = function(timestamp) {
this.animation = this.animation || {};
var delta = timestamp - (this.animation.time || 0);
this.animation.time = timestamp;
var duration = this.animation.remaining || 0;
var percent = Math.min(delta / duration, 1);
var currentX = this.currentX || 0;
var currentY = this.currentY || 0;
var targetX = this.animation.targetX || 0;
var targetY = this.animation.targetY || 0;
var rotateX = this.round(currentX + (targetX - currentX) * percent);
var rotateY = this.round(currentY + (targetY - currentY) * percent);
this.transform(rotateX, rotateY);
var remaining = duration - delta;
this.animation.remaining = remaining > 0 ? remaining : null;
if (remaining > 0) {
requestAnimationFrame(this.onAnimationFrame.bind(this));
}
};
Plate.prototype.onMouseEnter = function(event) {
var offset = this.offsetCoords(event);
this.update(offset.x, offset.y, this.options.animationDuration);
};
Plate.prototype.onMouseLeave = function(event) {
this.reset(this.options.animationDuration);
};
Plate.prototype.onMouseMove = function(event) {
var offset = this.offsetCoords(event);
this.update(offset.x, offset.y);
};
$.fn.plate = function(options) {
return this.each(function() {
var $element = $(this);
var plate = $element.data(namespace);
if (options === 'remove') {
plate.destroy();
$element.data(namespace, null);
} else {
if (!plate) {
plate = new Plate($element, options);
$element.data(namespace, plate);
plate.reset();
} else {
plate.config(options);
}
}
});
};
})(jQuery);
$('#ab12cd').plate()
<div id="ab12cd" styles="width:100%;height:100%">
<img src="http://eskipaper.com/images/dark-background-8.jpg" />
</div>
<script
src="https://code.jquery.com/jquery-3.2.1.min.js"
integrity="sha256-hwg4gsxgFZhOsEEamdOYGBf13FyQuiTwlAQgxVSNgt4="
crossorigin="anonymous"></script>
// please open in new window, most visible effect you cen see if you move mouse bottom left/right

Javascript Nested Function Call

I am trying to develop a javascript library that makes it easier for me to generate DOM Elements and edit their attributes. The problem I am having is that there is so many attributes for some elements that it is making for messy code. For instance I have to programmatically set the color of border, background, shadow, etc. using a method call before generation.
See setBorder Nested in function Div in jLibrary.php
function Div() {
Div.POSITION = {
STATIC : 'static',
ABSOLUTE : 'absolute',
RELATIVE : 'relative',
FIXED : 'fixed'
}
Div.BORDER = {
SOLID : 'solid',
DOTTED : 'dotted'
}
Div.ALIGN = {
LEFT : 0,
CENTER : 1,
RIGHT : 2,
TOP : 0,
MIDDLE : 1,
BOTTOM : 2
}
var ELEMENT;
var CSS;
var horizontalAlign;
var verticalAlign;
var colorQueue;
(function() {
this.div = document.createElement('div');
ELEMENT = this.div;
CSS = this.div.style;
colorQueue = 'rgb(' + new Array(0, 0, 0) + ')';
document.body.appendChild(this.div);
}());
this.setPosition = function(postype) {
if (!horizontalAlign && !verticalAlign) {
CSS.position = postype;
}
}
this.setBounds = function(x, y, width, height) {
CSS.left = x + 'px';
CSS.top = y + 'px';
CSS.width = width + 'px';
CSS.height = height + 'px';
}
this.setColorQueue = function(r, g, b) {
colorQueue = 'rgb(' + new Array(r, g, b) + ')';
alert(colorQueue);
}
this.setBackgroundColorToQueue = function(){
CSS.backgroundColor = colorQueue;
}
this.createShadow = function(x, y, width, height){
CSS.boxShadow = y + 'px ' + x + 'px ' + width + 'px ' + height + 'px ' + colorQueue;
}
this.createBorder = function(width,style){
CSS.border = width + 'px ' + style + ' ' + colorQueue;
/* Theoretical Method.
this.setColor = function(r,g,b){ //This will not work the way I want it...
CSS.border = 'rgb(' + new Array(r, g, b) + ')';
}
*/
}
this.rotateDiv = function(degrees){
CSS.transform = 'rotate(' + degrees + 'deg)';
}
this.horizontalAlign = function(horiz) {
var freeSpaceX = ((window.innerWidth - ELEMENT.offsetWidth) / 2);
var defPadding = '8px';
var defPaddingCenter;
var defPaddingRight;
var defPaddingLeft;
horizontalAlign = true;
if (CSS.position == 'relative' || CSS.position == 'static' || CSS.position == 'absolute') {
CSS.position = 'absolute';
defPaddingCenter = 4;
defPaddingRight = 4;
defPaddingLeft = 8;
} else if (CSS.position == 'fixed') {
defPaddingCenter = 4;
defPaddingRight = 4;
defPaddingLeft = 8;
}
if (horiz == 0) {
if (!verticalAlign) {
CSS.marginTop = defPadding;
}
CSS.marginLeft = defPaddingLeft + 'px';
} else if (horiz == 1) {
if (!verticalAlign) {
CSS.marginTop = defPadding;
}
CSS.marginLeft = freeSpaceX - defPaddingCenter + 'px';
} else if (horiz == 2) {
if (!verticalAlign) {
CSS.marginTop = defPadding;
}
CSS.marginLeft = (freeSpaceX - defPaddingRight) * 2 + 'px';
}
}
this.verticalAlign = function(vertical) {
var freeSpaceY = ((window.innerHeight - ELEMENT.offsetHeight) / 2);
var defPadding = '8px';
var defPaddingTop;
var defPaddingMid;
var defPaddingBot;
verticalAlign = true;
if (CSS.position == 'relative' || CSS.position == 'static') {
CSS.position = 'absolute';
}
defPaddingTop = 8;
defPaddingMid = 8;
defPaddingBot = 8;
if (vertical == 0) {
if (!horizontalAlign) {
CSS.marginLeft = defPadding;
}
CSS.marginTop = defPadding;
} else if (vertical == 1) {
if (!horizontalAlign) {
CSS.marginLeft = defPadding;
}
CSS.marginTop = freeSpaceY - defPaddingMid + 'px';
} else if (vertical == 2) {
if (!horizontalAlign) {
CSS.marginLeft = defPadding;
}
CSS.marginTop = (freeSpaceY * 2) - defPaddingBot + 'px';
}
}
}
setBorder Example in index.php
var div1 = new Div();
div1.setPosition(Div.POSITION.ABSOLUTE);
div1.setBounds(0,700, 200,200);
div1.setColorQueue(0,0,0); //This method must be called every time a different color is needed for a certain attribute.
div1.createBorder(5, Div.BORDER.SOLID); // I really want something like this --> div1.createBorder(5,Div.BORDER.SOLID).setColor(0,0,0);

You can try using the Builder pattern:
function DivBuilder() {
var color;
var border;
var position;
var bounds;
this.DivBuilder = function() {}
this.color = function(c) {
//set the color
this.color = c;
return this;
}
this.border = function(b) {
//set the border
this.border = b;
return this;
}
this.position = function(p) {
//set position
this.position = p;
return this;
}
this.bounds = function(b) {
//set bounds
this.border = b;
return this;
}
this.build = function () {
//build the new Div object with the properties of the builder
var d = new Div(this);
return d;
}
}
and then:
var divb = new DivBuilder();
divb.position().bounds().border().color();
var div = divb.buid();
Main advantage over the telescopic constructor pattern (well, the adaptation of it to javascript) is that you can choose easier which property you want to initialize without having to create many different constructor cases.

If you want to write this.createBorder(...).setColor(...) It means that createBorder should return an object with the setColor method...

Thanks to Sebas I was able to come up with this... Please vote up Sebas if this helped you.
Nested in this.createBorder()
this.createBorder = function(width) {
CSS.border = width + 'px';
function DivBorderBuilder() {
this.setColor = function(r, b, g) {
alert('color');
CSS.borderColor = 'rgb(' + new Array(r, g, b) + ')';
return this;
}
this.setStyle = function(s){
CSS.borderStyle = s;
return this;
}
}return new DivBorderBuilder();
}
Creating Border in index.php
<script>
var div1 = new Div();
div1.setPosition(Div.POSITION.ABSOLUTE);
div1.setBounds(0,700, 200,200);
div1.createBorder(5).setStyle(Div.BORDER.SOLID).setColor(255,0,0);// Works Perfectly Now !
</script>

Cloudzoom and woocommerce attributes

I cannot get cloudzoom to work with my woocommerce site, every time I choose an attribute ie size the main image disappears, it is like cloudzoom is trying to force an attribute image. I am absolutely pants at javascript and looking through the file I cannot see where I need to edit or delete the code. Any help would be greatly appreciated, I don't need the atribute image function to work at all so just stripping out the code would suit me. Here is the code...
(function ($) {
$(document).ready(function () {
$('.cloud-zoom, .cloud-zoom-gallery').CloudZoom();
});
function format(str) {
for (var i = 1; i < arguments.length; i++) {
str = str.replace('%' + (i - 1), arguments[i]);
}
return str;
}
function CloudZoom(jWin, opts) {
var sImg = $('img', jWin);
var img1;
var img2;
var zoomDiv = null;
var $mouseTrap = null;
var lens = null;
var $tint = null;
var softFocus = null;
var $ie6Fix = null;
var zoomImage;
var controlTimer = 0;
var cw, ch;
var destU = 0;
var destV = 0;
var currV = 0;
var currU = 0;
var filesLoaded = 0;
var mx,
my;
var ctx = this, zw;
// Display an image loading message. This message gets deleted when the images have loaded and the zoom init function is called.
// We add a small delay before the message is displayed to avoid the message flicking on then off again virtually immediately if the
// images load really fast, e.g. from the cache.
//var ctx = this;
setTimeout(function () {
// <img src="/images/loading.gif"/>
if ($mouseTrap === null) {
var w = jWin.width();
jWin.parent().append(format('<div style="width:%0px;position:absolute;top:75%;left:%1px;text-align:center" class="cloud-zoom-loading" >Loading...</div>', w / 3, (w / 2) - (w / 6))).find(':last').css('opacity', 0.5);
}
}, 200);
var ie6FixRemove = function () {
if ($ie6Fix !== null) {
$ie6Fix.remove();
$ie6Fix = null;
}
};
// Removes cursor, tint layer, blur layer etc.
this.removeBits = function () {
//$mouseTrap.unbind();
if (lens) {
lens.remove();
lens = null;
}
if ($tint) {
$tint.remove();
$tint = null;
}
if (softFocus) {
softFocus.remove();
softFocus = null;
}
ie6FixRemove();
$('.cloud-zoom-loading', jWin.parent()).remove();
};
this.destroy = function () {
jWin.data('zoom', null);
if ($mouseTrap) {
$mouseTrap.unbind();
$mouseTrap.remove();
$mouseTrap = null;
}
if (zoomDiv) {
zoomDiv.remove();
zoomDiv = null;
}
//ie6FixRemove();
this.removeBits();
// DON'T FORGET TO REMOVE JQUERY 'DATA' VALUES
};
// This is called when the zoom window has faded out so it can be removed.
this.fadedOut = function () {
if (zoomDiv) {
zoomDiv.remove();
zoomDiv = null;
}
this.removeBits();
//ie6FixRemove();
};
this.controlLoop = function () {
if (lens) {
var x = (mx - sImg.offset().left - (cw * 0.5)) >> 0;
var y = (my - sImg.offset().top - (ch * 0.5)) >> 0;
if (x < 0) {
x = 0;
}
else if (x > (sImg.outerWidth() - cw)) {
x = (sImg.outerWidth() - cw);
}
if (y < 0) {
y = 0;
}
else if (y > (sImg.outerHeight() - ch)) {
y = (sImg.outerHeight() - ch);
}
lens.css({
left: x,
top: y
});
lens.css('background-position', (-x) + 'px ' + (-y) + 'px');
destU = (((x) / sImg.outerWidth()) * zoomImage.width) >> 0;
destV = (((y) / sImg.outerHeight()) * zoomImage.height) >> 0;
currU += (destU - currU) / opts.smoothMove;
currV += (destV - currV) / opts.smoothMove;
zoomDiv.css('background-position', (-(currU >> 0) + 'px ') + (-(currV >> 0) + 'px'));
}
controlTimer = setTimeout(function () {
ctx.controlLoop();
}, 30);
};
this.init2 = function (img, id) {
filesLoaded++;
//console.log(img.src + ' ' + id + ' ' + img.width);
if (id === 1) {
zoomImage = img;
}
//this.images[id] = img;
if (filesLoaded === 2) {
this.init();
}
};
/* Init function start. */
this.init = function () {
// Remove loading message (if present);
$('.cloud-zoom-loading', jWin.parent()).remove();
/* Add a box (mouseTrap) over the small image to trap mouse events.
It has priority over zoom window to avoid issues with inner zoom.
We need the dummy background image as IE does not trap mouse events on
transparent parts of a div.
*/
$mouseTrap = jWin.parent().append(format("<div class='mousetrap' style='background-image:url(\".\");z-index:3;position:absolute;width:%0px;height:%1px;left:%2px;top:%3px;\'></div>", sImg.outerWidth(), sImg.outerHeight(), 0, 0)).find(':last');
//////////////////////////////////////////////////////////////////////
/* Do as little as possible in mousemove event to prevent slowdown. */
$mouseTrap.bind('mousemove', this, function (event) {
// Just update the mouse position
mx = event.pageX;
my = event.pageY;
});
//////////////////////////////////////////////////////////////////////
$mouseTrap.bind('mouseleave', this, function (event) {
clearTimeout(controlTimer);
//event.data.removeBits();
if(lens) { lens.fadeOut(299); }
if($tint) { $tint.fadeOut(299); }
if(softFocus) { softFocus.fadeOut(299); }
zoomDiv.fadeOut(300, function () {
ctx.fadedOut();
});
return false;
});
//////////////////////////////////////////////////////////////////////
$mouseTrap.bind('mouseenter', this, function (event) {
mx = event.pageX;
my = event.pageY;
zw = event.data;
if (zoomDiv) {
zoomDiv.stop(true, false);
zoomDiv.remove();
}
var xPos = opts.adjustX,
yPos = opts.adjustY;
var siw = sImg.outerWidth();
var sih = sImg.outerHeight();
var w = opts.zoomWidth;
var h = opts.zoomHeight;
if (opts.zoomWidth == 'auto') {
w = siw;
}
if (opts.zoomHeight == 'auto') {
h = sih;
}
//$('#info').text( xPos + ' ' + yPos + ' ' + siw + ' ' + sih );
var appendTo = jWin.parent(); // attach to the wrapper
switch (opts.position) {
case 'top':
yPos -= h; // + opts.adjustY;
break;
case 'right':
xPos += siw; // + opts.adjustX;
break;
case 'bottom':
yPos += sih; // + opts.adjustY;
break;
case 'left':
xPos -= w; // + opts.adjustX;
break;
case 'inside':
w = siw;
h = sih;
break;
// All other values, try and find an id in the dom to attach to.
default:
appendTo = $('#' + opts.position);
// If dom element doesn't exit, just use 'right' position as default.
if (!appendTo.length) {
appendTo = jWin;
xPos += siw; //+ opts.adjustX;
yPos += sih; // + opts.adjustY;
} else {
w = appendTo.innerWidth();
h = appendTo.innerHeight();
}
}
zoomDiv = appendTo.append(format('<div id="cloud-zoom-big" class="cloud-zoom-big" style="display:none;position:absolute;left:%0px;top:%1px;width:%2px;height:%3px;background-image:url(\'%4\');z-index:2;"></div>', xPos, yPos, w, h, zoomImage.src)).find(':last');
// Add the title from title tag.
if (sImg.attr('title') && opts.showTitle) {
zoomDiv.append(format('<div class="cloud-zoom-title">%0</div>', sImg.attr('title'))).find(':last').css('opacity', opts.titleOpacity);
}
// Fix ie6 select elements wrong z-index bug. Placing an iFrame over the select element solves the issue...
if ($.browser.msie && $.browser.version < 7) {
$ie6Fix = $('<iframe frameborder="0" src="#"></iframe>').css({
position: "absolute",
left: xPos,
top: yPos,
zIndex: 99,
width: w,
height: h
}).insertBefore(zoomDiv);
}
zoomDiv.fadeIn(500);
if (lens) {
lens.remove();
lens = null;
} /* Work out size of cursor */
cw = (sImg.outerWidth() / zoomImage.width) * zoomDiv.width();
ch = (sImg.outerHeight() / zoomImage.height) * zoomDiv.height();
// Attach mouse, initially invisible to prevent first frame glitch
lens = jWin.append(format("<div class = 'cloud-zoom-lens' style='display:none;z-index:1;position:absolute;width:%0px;height:%1px;opacity:0.4'></div>", cw, ch)).find(':last');
$mouseTrap.css('cursor', lens.css('cursor'));
var noTrans = false;
// Init tint layer if needed. (Not relevant if using inside mode)
if (opts.tint) {
/* lens.css('background', 'url("' + sImg.attr('src') + '")'); */
$tint = jWin.append(format('<div style="display:none;position:absolute; left:0px; top:0px; width:%0px; height:%1px; background-color:%2;" />', sImg.outerWidth(), sImg.outerHeight(), opts.tint)).find(':last');
$tint.css('opacity', opts.tintOpacity);
noTrans = true;
$tint.fadeIn(500);
}
if (opts.softFocus) {
lens.css('background', 'url("' + sImg.attr('src') + '")');
softFocus = jWin.append(format('<div style="position:absolute;display:none;top:2px; left:2px; width:%0px; height:%1px;" />', sImg.outerWidth() - 2, sImg.outerHeight() - 2, opts.tint)).find(':last');
softFocus.css('background', 'url("' + sImg.attr('src') + '")');
softFocus.css('opacity', 0.5);
noTrans = true;
softFocus.fadeIn(500);
}
if (!noTrans) {
lens.css('opacity', opts.lensOpacity);
}
if ( opts.position !== 'inside' ) { lens.fadeIn(500); }
// Start processing.
zw.controlLoop();
return; // Don't return false here otherwise opera will not detect change of the mouse pointer type.
});
};
img1 = new Image();
$(img1).load(function () {
ctx.init2(this, 0);
});
img1.src = sImg.attr('src');
img2 = new Image();
$(img2).load(function () {
ctx.init2(this, 1);
});
img2.src = jWin.attr('href');
}
$.fn.CloudZoom = function (options) {
// IE6 background image flicker fix
try {
document.execCommand("BackgroundImageCache", false, true);
} catch (e) {}
this.each(function () {
var relOpts, opts;
// Hmm...eval...slap on wrist.
eval('var a = {' + $(this).attr('rel') + '}');
relOpts = a;
if ($(this).is('.cloud-zoom')) {
$(this).css({
'position': 'relative',
'display': 'block'
});
$('img', $(this)).css({
'display': 'block'
});
// Wrap an outer div around the link so we can attach things without them becoming part of the link.
// But not if wrap already exists.
if ($(this).parent().attr('id') != 'wrap') {
$(this).wrap('<div id="wrap" style="top:0px;z-index:4;position:relative;"></div>');
}
opts = $.extend({}, $.fn.CloudZoom.defaults, options);
opts = $.extend({}, opts, relOpts);
$(this).data('zoom', new CloudZoom($(this), opts));
} else if ($(this).is('.cloud-zoom-gallery')) {
opts = $.extend({}, relOpts, options);
$(this).data('relOpts', opts);
$(this).bind('click', $(this), function (event) {
var data = event.data.data('relOpts');
// Destroy the previous zoom
$('#' + data.useZoom).data('zoom').destroy();
// Change the biglink to point to the new big image.
$('#' + data.useZoom).attr('href', event.data.attr('href'));
// Change the small image to point to the new small image.
$('#' + data.useZoom + ' img').attr('src', event.data.data('relOpts').smallImage);
// Init a new zoom with the new images.
$('#zoom-cb').attr('href', event.data.attr('href'));
$('#' + event.data.data('relOpts').useZoom).CloudZoom();
return false;
});
}
});
return this;
};
$.fn.CloudZoom.defaults = {
zoomWidth: 'auto',
zoomHeight: 'auto',
position: 'right',
tint: false,
tintOpacity: 0.5,
lensOpacity: 0.5,
softFocus: false,
smoothMove: 3,
showTitle: false,
titleOpacity: 0.5,
adjustX: 0,
adjustY: 0
};
})(jQuery);

box2dweb raycast

I am trying to get the distance between my character and the ground, I have found something that looks like it should do what I want but it has been written for another version of box2d.
Original:
float targetHeight = 3;
float springConstant = 100;
//make the ray at least as long as the target distance
b2Vec2 startOfRay = m_hovercarBody->GetPosition();
b2Vec2 endOfRay = m_hovercarBody->GetWorldPoint( b2Vec2(0,-5) );
overcarRayCastClosestCallback callback;
m_world->RayCast(&callback, startOfRay, endOfRay);
if ( callback.m_hit ) {
float distanceAboveGround = (startOfRay - callback.m_point).Length();
//dont do anything if too far above ground
if ( distanceAboveGround < targetHeight ) {
float distanceAwayFromTargetHeight = targetHeight - distanceAboveGround;
m_hovercarBody->ApplyForce( b2Vec2(0,springConstant*distanceAwayFromTargetHeight),
m_hovercarBody->GetWorldCenter() );
}
}
I have tried to change it to what I think it should be but it doesn't even call the callback.
var targetHeight = 3;
var springConstant = 100;
//make the ray at least as long as the target distance
startOfRay = new b2Vec2(m_hovercarBody.GetPosition());
endOfRay = new b2Vec(m_hovercarBody.GetWorldPoint( b2Vec2(0,-5)));
function callback(raycast){
if ( raycast.m_hit ) {
var distanceAboveGround = (startOfRay - raycast.m_point).Length();
//dont do anything if too far above ground
if ( distanceAboveGround < targetHeight ) {
var distanceAwayFromTargetHeight = targetHeight - distanceAboveGround;
m_hovercarBody.ApplyForce( b2Vec2(0,springConstant*distanceAwayFromTargetHeight),
m_hovercarBody.GetWorldCenter() );
}
}
}
m_world.RayCast(callback, startOfRay, endOfRay);
Any idea how to convert it to work with box2dweb?
Thanks

It might be that the original bit of code was written for a platform where the coordinate system works differently.
In a Canvas element, the coordinate system starts from the top left corner, meaning that m_hovercarBody.GetWorldPoint( b2Vec2(0,-5)) is checking for a point above the character, rather than below.
I'm not sure about the rest of the code but try changing that to m_hovercarBody.GetWorldPoint( b2Vec2(0,5)) and see what happens.
EDIT:
I think actually the problem is with the way you've structured your callback. Looking up the reference for the Raycast function would reveal more.
(The Javascript version of Box2D you're using is an automatic port of the Actionscript one. Given the two have fairly similar syntax, you can use the reference for Flash.)
The original code you posted seems to be C++, but I don't know much about its syntax. It seems there's some sort of class that does the raycasting (overcarRayCastClosestCallback). You can either look for that, or try and build your own callback function according to the first link I posted. It would be something along the lines of:
function customRaycastCallback(fixture, normal, fraction) {
// you can, for instance, check if fixture belongs to the ground
// or something else, then handle things accordingly
if( /* fixture belongs to ground */ ) {
// you've got the fraction of the original length of the raycast!
// you can use this to determine the distance
// between the character and the ground
return fraction;
}
else {
// continue looking
return 1;
}
}

Try running this on your browser. I coded this when I was learning sensor and RAYCAST in Box2Dweb. Hope it helps.
<html>
<head>
<title>Box2dWeb Demo</title>
</head>
<body>
<canvas id="canvas" width="600" height="420" style="background-color:#333333;" ></canvas>
<div id="cc" style="position:absolute; right:0; top:100px; width:500px; height:50px; margin:0;"></div>
</body>
<script type="text/javascript" src="Box2dWeb-2.1.a.3.js"></script>
<script type="text/javascript" src="jquery-1.7.2.js"></script>
<script type="text/javascript">
var b2Vec2 = Box2D.Common.Math.b2Vec2
, b2BodyDef = Box2D.Dynamics.b2BodyDef
, b2Body = Box2D.Dynamics.b2Body
, b2FixtureDef = Box2D.Dynamics.b2FixtureDef
, b2World = Box2D.Dynamics.b2World
, b2PolygonShape = Box2D.Collision.Shapes.b2PolygonShape
, b2CircleShape = Box2D.Collision.Shapes.b2CircleShape
, b2ContactFilter = Box2D.Dynamics.b2ContactFilter
, b2MouseJointDef = Box2D.Dynamics.Joints.b2MouseJointDef
, b2DebugDraw = Box2D.Dynamics.b2DebugDraw
, b2Fixture = Box2D.Dynamics.b2Fixture
, b2AABB = Box2D.Collision.b2AABB
, b2WorldManifold = Box2D.Collision.b2WorldManifold
, b2ManifoldPoint = Box2D.Collision.b2ManifoldPoint
, b2RayCastInput = Box2D.Collision.b2RayCastInput
, b2RayCastOutput = Box2D.Collision.b2RayCastOutput
, b2Color = Box2D.Common.b2Color;
var world = new b2World(new b2Vec2(0,10), true);
var canvas = $('#canvas');
var context = canvas.get(0).getContext('2d');
//box
var bodyDef = new b2BodyDef;
bodyDef.type = b2Body.b2_dynamicBody;
bodyDef.position.Set(9,7);
bodyDef.userData = 'box';
var fixDef = new b2FixtureDef;
fixDef.filter.categoryBits = 1;
fixDef.density = 10.0;
fixDef.friction = 0.5;
fixDef.restitution = .5;
fixDef.shape = new b2PolygonShape;
fixDef.shape.SetAsBox(1,5);
var box1 = world.CreateBody(bodyDef);
box1.CreateFixture(fixDef);
//circle
var bodyDef2 = new b2BodyDef;
bodyDef2.type = b2Body.b2_dynamicBody;
bodyDef2.position.Set(4,8);
bodyDef2.userData = 'obj';
var fixDef2 = new b2FixtureDef;
fixDef2.filter.categoryBits = 2;
fixDef2.filter.maskBits = 13;
fixDef2.density = 10.0;
fixDef2.friction = 0.5;
fixDef2.restitution = .2;
fixDef2.shape = new b2CircleShape(1);
//circlesensor
var cc = new b2FixtureDef;
cc.shape = new b2CircleShape(2);
cc.shape.SetLocalPosition(new b2Vec2(0 ,0));
cc.density = 0;
cc.isSensor = true;
cc.filter.categoryBits = 8;
var wheel = world.CreateBody(bodyDef2);
wheel.CreateFixture(fixDef2);
wheel.CreateFixture(cc);
//create a ground
var holderDef = new b2BodyDef;
holderDef.type = b2Body.b2_staticBody;
holderDef.userData = "ground";
holderDef.position.Set(10, 14);
var fd = new b2FixtureDef;
fd.filter.categoryBits = 4;
fd.shape = new b2PolygonShape;
fd.shape.SetAsBox(10,1);
var ground = world.CreateBody(holderDef);
ground.CreateFixture(fd);
//create another static body
var holderDef = new b2BodyDef;
holderDef.type = b2Body.b2_staticBody;
holderDef.position.Set(10, 20);
var temp = world.CreateBody(holderDef);
temp.CreateFixture(fd);
var c=0;
$(window).keydown(function(e) {
$('#aa').html(++c);
code = e.keyCode;
if(c==1) {
if(code == 38 && onground)
wheel.SetLinearVelocity(new b2Vec2(0,-10));
if(code == 39)
wheel.ApplyForce(new b2Vec2(1000,0), box1.GetWorldPoint(new b2Vec2(0,0)));
if(code == 37)
wheel.ApplyForce(new b2Vec2(-1000,0), box1.GetWorldPoint(new b2Vec2(0,0)));
}
});
$(window).keyup(function(e) {
c=0;
});
var listener = new Box2D.Dynamics.b2ContactListener;
listener.BeginContact = function(contact) {
if(contact.GetFixtureA().GetBody().GetUserData()== 'obj' || contact.GetFixtureB().GetBody().GetUserData()== 'obj' ) // think about why we don't use fixture's userData directly.
onground = true;// don't put 'var' here!
fxA=contact.GetFixtureA();
fxB=contact.GetFixtureB();
sA=fxA.IsSensor();
sB=fxB.IsSensor();
if((sA && !sB) || (sB && !sA)) {
if(sA) {
$('#cc').prepend(contact.GetFixtureB().GetBody().GetUserData() + ' is in the viscinity of body '+contact.GetFixtureA().GetBody().GetUserData()+'<br>');
}
else {
$('#cc').prepend(contact.GetFixtureA().GetBody().GetUserData() + ' is in the viscinity of body '+contact.GetFixtureB().GetBody().GetUserData()+'<br>');
}
}
}
listener.EndContact = function(contact) {
if (contact.GetFixtureA().GetBody().GetUserData()== 'obj' || contact.GetFixtureB().GetBody().GetUserData()== 'obj' )
onground = false;
}
var debugDraw = new b2DebugDraw();
debugDraw.SetSprite ( document.getElementById ("canvas").getContext ("2d"));
debugDraw.SetDrawScale(30); //define scale
debugDraw.SetAlpha(1);
debugDraw.SetFillAlpha(.3); //define transparency
debugDraw.SetLineThickness(1.0);
debugDraw.SetFlags(b2DebugDraw.e_shapeBit | b2DebugDraw.e_jointBit);
world.SetDebugDraw(debugDraw);
window.setInterval(update,1000/60);
//mouse
var mouseX, mouseY, mousePVec, isMouseDown, selectedBody, mouseJoint;
var canvasPosition = getElementPosition(document.getElementById("canvas"));
document.addEventListener("mousedown", function(e) {
isMouseDown = true;
handleMouseMove(e);
document.addEventListener("mousemove", handleMouseMove, true);
}, true);
document.addEventListener("mouseup", function() {
document.removeEventListener("mousemove", handleMouseMove, true);
isMouseDown = false;
mouseX = undefined;
mouseY = undefined;
}, true);
function handleMouseMove(e) {
mouseX = (e.clientX - canvasPosition.x) / 30;
mouseY = (e.clientY - canvasPosition.y) / 30;
};
function getBodyAtMouse() {
mousePVec = new b2Vec2(mouseX, mouseY);
var aabb = new b2AABB();
aabb.lowerBound.Set(mouseX - 0.001, mouseY - 0.001);
aabb.upperBound.Set(mouseX + 0.001, mouseY + 0.001);
// Query the world for overlapping shapes.
selectedBody = null;
world.QueryAABB(getBodyCB, aabb);
return selectedBody;
}
function getBodyCB(fixture) {
if(fixture.GetBody().GetType() != b2Body.b2_staticBody) {
if(fixture.GetShape().TestPoint(fixture.GetBody().GetTransform(), mousePVec)) {
selectedBody = fixture.GetBody();
return false;
}
}
return true;
}
//at global scope
var currentRayAngle = 0;
var input = new b2RayCastInput();
var output = new b2RayCastOutput();
var b = new b2BodyDef();
var f = new b2FixtureDef();
var closestFraction = 1;
var intersectionNormal = new b2Vec2(0,0);
var intersectionPoint = new b2Vec2();
rayLength = 25; //long enough to hit the walls
var p1 = new b2Vec2( 11, 7 ); //center of scene
var p2 = new b2Vec2();
var normalEnd = new b2Vec2();
function update() {
if(isMouseDown && (!mouseJoint)) {
var body = getBodyAtMouse();
if(body) {
var md = new b2MouseJointDef();
md.bodyA = world.GetGroundBody();
md.bodyB = body;
md.target.Set(mouseX, mouseY);
md.collideConnected = true;
md.maxForce = 300.0 * body.GetMass();
mouseJoint = world.CreateJoint(md);
body.SetAwake(true);
}
}
if(mouseJoint) {
if(isMouseDown) {
mouseJoint.SetTarget(new b2Vec2(mouseX, mouseY));
} else {
world.DestroyJoint(mouseJoint);
mouseJoint = null;
}
}
world.Step(1 / 60, 10, 10);
world.DrawDebugData();
world.ClearForces();
world.SetContactListener(listener);
ray();
};
function ray() {
//in Step() function
var k = 360/20;
var t = k/60;
var DEGTORAD = Math.PI/180;
currentRayAngle += t * DEGTORAD; //one revolution every 20 seconds
//console.log(currentRayAngle*(180/Math.PI));
//calculate points of ray
p2.x = p1.x + rayLength * Math.sin(currentRayAngle);
p2.y = p1.y + rayLength * Math.cos(currentRayAngle);
input.p1 = p1;
input.p2 = p2;
input.maxFraction = 1;
closestFraction = 1;
var b = new b2BodyDef();
var f = new b2FixtureDef();
for(b = world.GetBodyList(); b; b = b.GetNext()) {
for(f = b.GetFixtureList(); f; f = f.GetNext()) {
if(!f.RayCast(output, input))
continue;
else if(output.fraction < closestFraction) {
closestFraction = output.fraction;
intersectionNormal = output.normal;
}
}
}
intersectionPoint.x = p1.x + closestFraction * (p2.x - p1.x);
intersectionPoint.y = p1.y + closestFraction * (p2.y - p1.y);
normalEnd.x = intersectionPoint.x + intersectionNormal.x;
normalEnd.y = intersectionPoint.y + intersectionNormal.y;
context.strokeStyle = "rgb(255, 255, 255)";
context.beginPath(); // Start the path
context.moveTo(p1.x*30,p1.y*30); // Set the path origin
context.lineTo(intersectionPoint.x*30, intersectionPoint.y*30); // Set the path destination
context.closePath(); // Close the path
context.stroke();
context.beginPath(); // Start the path
context.moveTo(intersectionPoint.x*30, intersectionPoint.y*30); // Set the path origin
context.lineTo(normalEnd.x*30, normalEnd.y*30); // Set the path destination
context.closePath(); // Close the path
context.stroke(); // Outline the path
}
//helpers
//http://js-tut.aardon.de/js-tut/tutorial/position.html
function getElementPosition(element) {
var elem=element, tagname="", x=0, y=0;
while((typeof(elem) == "object") && (typeof(elem.tagName) != "undefined")) {
y += elem.offsetTop;
x += elem.offsetLeft;
tagname = elem.tagName.toUpperCase();
if(tagname == "BODY")
elem=0;
if(typeof(elem) == "object") {
if(typeof(elem.offsetParent) == "object")
elem = elem.offsetParent;
}
}
return {x: x, y: y};
}
</script>
</html>

Here's a Raycast in Box2dWeb that I got working:
var p1 = new b2Vec2(body.GetPosition().x, body.GetPosition().y); //center of scene
var p2 = new b2Vec2(body.GetPosition().x, body.GetPosition().y + 5); //center of scene
world.RayCast(function(x){
console.log("You've got something under you");
}, p1,p2);