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How to drag images in JS

I have a large background image and some much smaller images for the user to drag around on the background. I need this to be efficient in terms of performance, so i'm trying to avoid libraries. I'm fine with drag 'n' drop if it work's well, but im trying to get drag.
Im pretty much trying to do this. But after 8 years there must be a cleaner way to do this right?
I currently have a drag 'n' drop system that almost works, but when i drop the smaller images, they are just a little off and it's very annoying. Is there a way to fix my code, or do i need to take a whole different approach?
This is my code so far:
var draggedPoint;
function dragStart(event) {
draggedPoint = event.target; // my global var
}
function drop(event) {
event.preventDefault();
let xDiff = draggedPoint.x - event.pageX;
let yDiff = draggedPoint.y - event.pageY;
let left = draggedPoint.style.marginLeft; // get margins
let top = draggedPoint.style.marginTop;
let leftNum = Number(left.substring(0, left.length - 2)); // cut off px from the end
let topNum = Number(top.substring(0, top.length - 2));
let newLeft = leftNum - xDiff + "px" // count new margins and put px back to the end
let newTop = topNum - yDiff + "px"
draggedPoint.style.marginLeft = newLeft;
draggedPoint.style.marginTop = newTop;
}
function allowDrop(event) {
event.preventDefault();
}
let imgs = [
"https://upload.wikimedia.org/wikipedia/commons/6/67/Orange_juice_1_edit1.jpg",
"https://upload.wikimedia.org/wikipedia/commons/f/ff/Solid_blue.svg",
"https://upload.wikimedia.org/wikipedia/commons/b/b4/Litoria_infrafrenata_-_Julatten.jpg"
]
/* my smaller images: */
for (let i = 0; i < 6; i++) {
let sensor = document.createElement("img");
sensor.src = imgs[i % imgs.length];
sensor.alt = i;
sensor.draggable = true;
sensor.classList.add("sensor");
sensor.style.marginLeft = `${Math.floor(Math.random() * 900)}px`
sensor.style.marginTop = `${Math.floor(Math.random() * 500)}px`
sensor.onclick = function() {
sensorClick(logs[i].id)
};
sensor.addEventListener("dragstart", dragStart, null);
let parent = document.getElementsByClassName("map")[0];
parent.appendChild(sensor);
}
<!-- my html: -->
<style>
.map {
width: 900px;
height: 500px;
align-content: center;
margin: 150px auto 150px auto;
}
.map .base {
position: absolute;
width: inherit;
height: inherit;
}
.map .sensor {
position: absolute;
width: 50px;
height: 50px;
}
</style>
<div class="map" onDrop="drop(event)" ondragover="allowDrop(event)">
<img src='https://upload.wikimedia.org/wikipedia/commons/f/f7/Plan-Oum-el-Awamid.jpg' alt="pohja" class="base" draggable="false">
<div>

With the answers from here and some time i was able to get a smooth drag and click with pure js.
Here is a JSFiddle to see it in action.
let maxLeft;
let maxTop;
const minLeft = 0;
const minTop = 0;
let timeDelta;
let imgs = [
"https://upload.wikimedia.org/wikipedia/commons/6/67/Orange_juice_1_edit1.jpg",
"https://upload.wikimedia.org/wikipedia/commons/f/ff/Solid_blue.svg",
"https://upload.wikimedia.org/wikipedia/commons/b/b4/Litoria_infrafrenata_-_Julatten.jpg"
]
var originalX;
var originalY;
window.onload = function() {
document.onmousedown = startDrag;
document.onmouseup = stopDrag;
}
function sensorClick () {
if (Date.now() - timeDelta < 150) { // check that we didn't drag
createPopup(this);
}
}
// create a popup when we click
function createPopup(parent) {
let p = document.getElementById("popup");
if (p) {
p.parentNode.removeChild(p);
}
let popup = document.createElement("div");
popup.id = "popup";
popup.className = "popup";
popup.style.top = parent.y - 110 + "px";
popup.style.left = parent.x - 75 + "px";
let text = document.createElement("span");
text.textContent = parent.id;
popup.appendChild(text);
var map = document.getElementsByClassName("map")[0];
map.appendChild(popup);
}
// when our base is loaded
function baseOnLoad() {
var map = document.getElementsByClassName("map")[0];
let base = document.getElementsByClassName("base")[0];
maxLeft = base.width - 50;
maxTop = base.height - 50;
/* my smaller images: */
for (let i = 0; i < 6; i++) {
let sensor = document.createElement("img");
sensor.src = imgs[i % imgs.length];
sensor.alt = i;
sensor.id = i;
sensor.draggable = true;
sensor.classList.add("sensor");
sensor.classList.add("dragme");
sensor.style.left = `${Math.floor(Math.random() * 900)}px`
sensor.style.top = `${Math.floor(Math.random() * 500)}px`
sensor.onclick = sensorClick;
let parent = document.getElementsByClassName("map")[0];
parent.appendChild(sensor);
}
}
function startDrag(e) {
timeDelta = Date.now(); // get current millis
// determine event object
if (!e) var e = window.event;
// prevent default event
if(e.preventDefault) e.preventDefault();
// IE uses srcElement, others use target
targ = e.target ? e.target : e.srcElement;
originalX = targ.style.left;
originalY = targ.style.top;
// check that this is a draggable element
if (!targ.classList.contains('dragme')) return;
// calculate event X, Y coordinates
offsetX = e.clientX;
offsetY = e.clientY;
// calculate integer values for top and left properties
coordX = parseInt(targ.style.left);
coordY = parseInt(targ.style.top);
drag = true;
document.onmousemove = dragDiv; // move div element
return false; // prevent default event
}
function dragDiv(e) {
if (!drag) return;
if (!e) var e = window.event;
// move div element and check for borders
let newLeft = coordX + e.clientX - offsetX;
if (newLeft < maxLeft && newLeft > minLeft) targ.style.left = newLeft + 'px'
let newTop = coordY + e.clientY - offsetY;
if (newTop < maxTop && newTop > minTop) targ.style.top = newTop + 'px'
return false; // prevent default event
}
function stopDrag() {
if (typeof drag == "undefined") return;
if (drag) {
if (Date.now() - timeDelta > 150) { // we dragged
let p = document.getElementById("popup");
if (p) {
p.parentNode.removeChild(p);
}
} else {
targ.style.left = originalX;
targ.style.top = originalY;
}
}
drag = false;
}
.map {
width: 900px;
height: 500px;
margin: 50px
position: relative;
}
.map .base {
position: absolute;
width: inherit;
height: inherit;
}
.map .sensor {
display: inline-block;
position: absolute;
width: 50px;
height: 50px;
}
.dragme {
cursor: move;
left: 0px;
top: 0px;
}
.popup {
position: absolute;
display: inline-block;
width: 200px;
height: 100px;
background-color: #9FC990;
border-radius: 10%;
}
.popup::after {
content: "";
position: absolute;
top: 100%;
left: 50%;
margin-left: -10px;
border-width: 10px;
border-style: solid;
border-color: #9FC990 transparent transparent transparent;
}
.popup span {
width: 90%;
margin: 10px;
display: inline-block;
text-align: center;
}
<div class="map" width="950px" height="500px">
<img src='https://upload.wikimedia.org/wikipedia/commons/f/f7/Plan-Oum-el-Awamid.jpg' alt="pohja" class="base" draggable="false" onload="baseOnLoad()">
<div>

Moving the square using mousedown event on front end

Practicing some front end stuff just by using addEventListener. What I am trying to achieve here is that : click the square and then hold the mouse while moving the square to another place on the page and stop moving by release the mouse. Something is not right as the square seems to move in one direction only. Need some help here.
#square_cursor {
position: relative;
left: 109px;
top: 109px;
height: 50px;
width: 50px;
background-color: rgb(219, 136, 136);
border: 5px rgb(136, 219, 219) solid;
cursor: pointer;
}
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Drag and Drop</title>
<link rel="stylesheet" href="styles.css">
</head>
<body>
<div id='square_cursor'></div>
<script>
let mouse_over_detector = false; //move the mouse over WITHOUT clicking
let mouse_click_detector = false; //clicking the mouse WITHOUT moveover
let drag_detector = false; //move and holding the mouse together
let window_click_detector = false;
let window_motion_detector = false;
let position_x = 0;
let position_y = 0;
let new_position_x = 0;
let new_position_y = 0;
window.addEventListener('mousedown', () => {
window_click_detector = true;
})
window.addEventListener('mouseup', () => {
window_click_detector = false;
brick.style.backgroundColor = 'rgb(219, 136, 136)';
})
let brick = document.getElementById('square_cursor');
//done
brick.addEventListener('mousedown', (event) => {
position_x = event.clientX;
position_y = event.clientY;
mouse_click_detector = true;
brick.style.backgroundColor = 'yellow';
})
brick.addEventListener('mousemove', (event) => {
if (mouse_click_detector === true) {
new_position_x = event.clientX;
new_position_y = event.clientY;
dragAndDrop(position_x, position_y, event.offsetX, event.offsetY);
}
});
brick.addEventListener('mouseout', () => {
mouse_over_detector = false;
mouse_click_detector = false;
})
brick.addEventListener('mouseup', () => {
mouse_click_detector = false;
})
function dragAndDrop(a, b, c, d) {
console.log('new x: ')
console.log(a - c);
console.log('new y: ')
console.log(b - d);
brick.style.left = a - c + 'px'
brick.style.top = b - d + 'px';
}
</script>
</body>
</html>

SOLVED IT THIS MORNING by using just addEventListener wooohoooo!
So the keys here are, first, being able to identify the DOM hierarchy and second, knowing what clientX does for the selected element. I am going to post my solution in snippet mode.
But I am still gonna give a vote to the 1st answer.
#square_cursor{
position:absolute;
left:109px;
top:109px;
height:50px;
width:50px;
background-color: rgb(219, 136, 136);
border:5px rgb(136, 219, 219) solid;
cursor: pointer;
}
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Drag and Drop</title>
<link rel="stylesheet" href="styles.css">
</head>
<body>
<div id='square_cursor'></div>
<script>
let mouse_click_detector = false; //clicking the mouse WITHOUT moveover
let window_click_detector = false;
let position_x = 0;
let position_y = 0;
let click_position_x = 0;
let click_position_y = 0;
let brick = document.getElementById('square_cursor');
brick.addEventListener('mousedown', () => {
mouse_click_detector = true
})
window.addEventListener('mouseup', () => {
mouse_click_detector = false;
window_click_detector = false;
brick.style.backgroundColor = 'rgb(219, 136, 136)';
})
window.addEventListener('mousedown', (event) => {
if (mouse_click_detector === true) {
window_click_detector = true;
brick.style.backgroundColor = 'yellow';
click_position_x = event.offsetX;
click_position_y = event.offsetY;
}
})
window.addEventListener('mousemove', (event) => {
if (mouse_click_detector === true) {
position_x = event.clientX;
position_y = event.clientY;
brick.style.left = position_x - click_position_x + 'px';
brick.style.top = position_y - click_position_y + 'px';
}
})
</script>
</body>
</html>
"The most personal is the most creative" --- Martin Scorsese

Something like this..
//Make the DIV element draggable:
dragElement(document.getElementById("mydiv"));
function dragElement(elmnt) {
var pos1 = 0, pos2 = 0, pos3 = 0, pos4 = 0;
if (document.getElementById(elmnt.id + "header")) {
/* if present, the header is where you move the DIV from:*/
document.getElementById(elmnt.id + "header").onmousedown = dragMouseDown;
} else {
/* otherwise, move the DIV from anywhere inside the DIV:*/
elmnt.onmousedown = dragMouseDown;
}
function dragMouseDown(e) {
e = e || window.event;
e.preventDefault();
// get the mouse cursor position at startup:
pos3 = e.clientX;
pos4 = e.clientY;
document.onmouseup = closeDragElement;
// call a function whenever the cursor moves:
document.onmousemove = elementDrag;
}
function elementDrag(e) {
e = e || window.event;
e.preventDefault();
// calculate the new cursor position:
pos1 = pos3 - e.clientX;
pos2 = pos4 - e.clientY;
pos3 = e.clientX;
pos4 = e.clientY;
// set the element's new position:
elmnt.style.top = (elmnt.offsetTop - pos2) + "px";
elmnt.style.left = (elmnt.offsetLeft - pos1) + "px";
}
function closeDragElement() {
/* stop moving when mouse button is released:*/
document.onmouseup = null;
document.onmousemove = null;
}
}
#mydiv {
position: absolute; /* NECESSARY */
background-color: dodgerblue;
border: 1px solid #d3d3d3;
height: 20px;
width: 20px;
}
<div id="mydiv">
</div>

Minimalist code,
with simplified calculations by transform: translate(x,y).
const myDiv = document.querySelector('#my-div');
myDiv.ref_ms = { x: 0, y: 0 };
myDiv.addEventListener('mousedown', (e) =>
{
myDiv.ref_ms.x = e.clientX;
myDiv.ref_ms.y = e.clientY;
myDiv.classList.add('movCursor')
if (myDiv.style.transform !== '')
{
let [ mx, my ] = myDiv.style.transform.match(/-?\d*\.?\d+/g).map(Number);
myDiv.ref_ms.x -= mx;
myDiv.ref_ms.y -= my;
}
})
window.addEventListener('mousemove', e =>
{
if (myDiv.classList.contains('movCursor')
&& e.clientX > 0 && e.clientY > 0 )
{
myDiv.style = `transform: translate(${e.clientX - myDiv.ref_ms.x}px, ${e.clientY - myDiv.ref_ms.y}px);`;
}
})
window.addEventListener('mouseup', () =>
{
myDiv.classList.remove('movCursor')
})
#my-div {
background : dodgerblue;
border : 1px solid #d3d3d3;
height : 50px;
width : 50px;
margin : 30px;
cursor : grab;
}
.movCursor {
cursor : grabbing !important;
}
<div id="my-div"></div>

Javascript Prevent Draggable div outside parent div

I have draggable div. I want this draggable div to be restricted within parent using javascript. I know how to prevent draggable div using jquery UI draggable plugin. But I am not sure how to restrict draggable using native javascript. Please find below my code:
<!DOCTYPE HTML>
<html>
<head>
<style>
.draggabletarget {
float: left;
width: 100px;
height: 35px;
margin: 15px;
padding: 10px;
border: 1px solid #aaaaaa;
}
</style>
</head>
<body>
<div class="parent" style="border:1px solid red;height:600px;width:600px;">
<div class="draggabletarget" ondragstart="dragStart(event)" ondrag="dragging(event)" draggable="true" id="dragtarget">
<p >Drag me!</p>
</div>
</div>
<script>
function dragStart(event) {
event.dataTransfer.setData("Text", event.target.id);
}
function dragging(event) {
document.getElementById("demo").innerHTML = "The p element is being dragged";
}
function allowDrop(event) {
event.preventDefault();
}
</script>
</body>
</html>
In this code i have a div with class parent. I want my draggable div whose class is draggabletarget shouldn't drag outside the parent div. How can i do this in native javascript. Please suggest

function $(el){
return document.getElementById(el);
}
var isDragging = false;
var tzdragg = function(){
return {
move : function(divid,xpos,ypos){
var a = $(divid);
$(divid).style.left = xpos + 'px';
$(divid).style.top = ypos + 'px';
},
setDragging : function() {
isDragging = true;
},
resetDragging : function() {
isDragging = false;
},
startMoving : function(evt){
evt = evt || window.event;
var posX = evt.clientX,
posY = evt.clientY,
a = $('elem'),
divTop = a.style.top,
divLeft = a.style.left;
divTop = divTop.replace('px','');
divLeft = divLeft.replace('px','');
var diffX = posX - divLeft,
diffY = posY - divTop;
document.onmousemove = function(evt){
evt = evt || window.event;
var posX = evt.clientX,
posY = evt.clientY,
aX = posX - diffX,
aY = posY - diffY;
var boun=document.getElementById("parent").offsetWidth-document.getElementById("elem").offsetWidth;
if((aX>0)&&(aX<boun)&&(aY>0)&&(aY<boun))
tzdragg.move('elem',aX,aY);
}
},
stopMoving : function(){
var a = document.createElement('script');
document.onmousemove = function(){}
if(!isDragging) {
console.log('clicked');
}
},
}
}();
#elem
{
position: absolute;
width: 100px;
height: 100px;
background-color: black;
-webkit-user-select: none;
-moz-user-select: none;
-o-user-select: none;
-ms-user-select: none;
-khtml-user-select: none;
user-select: none;
cursor: default;
}
<div style="height:400px; width:400px; border:solid 1px black;position: absolute;top: 0;
left: 0;" id='parent'>
<div id='elem' onmousedown='tzdragg.resetDragging();tzdragg.startMoving(event);' onmouseup='tzdragg.stopMoving();' onmousemove='tzdragg.setDragging();'
>
</div>
</div>

If you need to use pure javascript.
<div id='container'>Drag the box around</div>
<div id='slider'></div>
body {
background-color : lightgray;
}
#container {
position : fixed;
border-radius : 10px;
background-color : brown;
border : solid 1px black;
font : 15px arial,sans-serif;
text-align : center;
}
#slider {
position : fixed;
border-radius : 10px;
background: black;
}
div {
cursor : default;
}
document.onselectstart = function(e) {
e.preventDefault();
return false;
}
var slider = document.getElementById('slider'),container = document.getElementById('container');
document.mouseState = 'up';
slider.mouseState = 'up';
slider.lastMousePosY = null;
slider.lastMousePosX = null;
slider.proposedNewPosY = parseInt(slider.style.top, 10); //converts '10px' to 10
slider.proposedNewPosX = parseInt(slider.style.left, 10);
slider.style.top = '40px';
slider.style.left = '40px';
slider.style.height = '60px';
slider.style.width = '60px';
container.style.top = '20px';
container.style.left = '20px';
container.style.height = '200px';
container.style.width = '400px';
document.onmousedown = function() {
document.mouseState = 'down';
};
document.onmouseup = function() {
document.mouseState = 'up';
slider.mouseState = 'up';
};
slider.onmousedown = function(e) {
slider.lastMousePosY = e.pageY;
slider.lastMousePosX = e.pageX;
slider.mouseState = 'down';
document.mouseState = 'down';
};
slider.onmouseup = function(e) {
slider.mouseState = 'up';
document.mouseState = 'up';
};
var getAtInt = function getAtInt(obj, attrib) {
return parseInt(obj.style[attrib], 10);
};
document.onmousemove = function(e) {
if ((document.mouseState === 'down') && (slider.mouseState === 'down')) {
slider.proposedNewPosY = getAtInt(slider, 'top') + e.pageY - slider.lastMousePosY;
slider.proposedNewPosX = getAtInt(slider, 'left') + e.pageX - slider.lastMousePosX;
if (slider.proposedNewPosY < getAtInt(container, 'top')) {
slider.style.top = container.style.top;
} else if (slider.proposedNewPosY > getAtInt(container, 'top') + getAtInt(container, 'height') - getAtInt(slider, 'height')) {
slider.style.top = getAtInt(container, 'top') + getAtInt(container, 'height') - getAtInt(slider, 'height') + 'px';
} else {
slider.style.top = slider.proposedNewPosY + 'px';
}
if (slider.proposedNewPosX < getAtInt(container, 'left')) {
slider.style.left = container.style.left;
} else if (slider.proposedNewPosX > getAtInt(container, 'left') + getAtInt(container, 'width') - getAtInt(slider, 'width')) {
slider.style.left = getAtInt(container, 'left') + getAtInt(container, 'width') - getAtInt(slider, 'width') + 'px';
} else {
slider.style.left = slider.proposedNewPosX + 'px';
}
slider.lastMousePosY = e.pageY;
slider.lastMousePosX = e.pageX;
}
};
here is working example

Javascript move all childs inside div element

I'm trying to create a simple drag function that moves all childs inside a div tag depending on mouse movement, in simple world I calculate deltaX and deltaY and apply those to all childs inside a div by changing style.top and style.left. As regarding the X coordinate it works well while Y doesn't work (only increase) and I cannt explain why. This is what I have done
//Make the DIV element draggagle:
dragElement(document.getElementById(("mydiv")));
function dragElement(elmnt) {
var deltaX = 0, deltaY = 0, initX = 0, initY = 0;
var flag=true;
elmnt.onmousedown = dragMouseDown;
var childrens;
function dragMouseDown(e) {
e = e || window.event;
//console.log("dragMouseDown: "+e.clientX+" "+e.clientY);
childrens = document.getElementById("mydiv").querySelectorAll(".child");
// get the mouse cursor position at startup:
initX = e.clientX;
initY = e.clientY;
document.onmouseup = closeDragElement;
// call a function whenever the cursor moves:
document.onmousemove = elementDrag;
}
function elementDrag(e) {
if(flag){
flag=false;
e = e || window.event;
// calculate the new cursor position:
deltaX = e.clientX-initX;
deltaY = e.clientY-initY;
console.log("deltaX: "+deltaX+" deltaY: "+deltaY);
for (var i = 0; i < childrens.length; i++) {
//console.log("childrens[i].offsetTop: "+childrens[i].offsetTop+" childrens[i].offsetLeft: "+childrens[i].offsetLeft);
childrens[i].style.top = (childrens[i].offsetTop + deltaY) + "px"; // dont work (only increase)
childrens[i].style.left = (childrens[i].offsetLeft + deltaX) + "px";
}
initX = e.clientX;
initY = e.clientY;
deltaX=0;
deltaY=0;
flag=true;
}
}
function closeDragElement() {
/* stop moving when mouse button is released:*/
document.onmouseup = null;
document.onmousemove = null;
}
}
#mydiv {
position: fixed;
z-index: 9;
background-color: #f1f1f1;
text-align: center;
width:400px;
height:400px;
border: 1px solid #d3d3d3;
}
.child {
position: relative;
padding: 10px;
cursor: move;
z-index: 10;
background-color: #2196F3;
color: #fff;
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<h1>Draggable DIV Element</h1>
<p>Click and hold the mouse button down while moving the DIV element</p>
<div id="mydiv" style="background-color:blue">
<p class="child" style="background-color:red">Move 1</p>
</div>

Try something like this:
dragElement(document.getElementById(("mydiv")));
function dragElement(elmnt) {
var deltaX = 0,
deltaY = 0,
initX = 0,
initY = 0;
var flag = true;
elmnt.onmousedown = dragMouseDown;
var childrens;
function dragMouseDown(e) {
e = e || window.event;
childrens = document.getElementById("mydiv").querySelectorAll(".child");
for (var i = 0; i < childrens.length; i++) {
childrens[i].style.top = childrens[i].style.top == "" ? "0px" : childrens[i].style.top;
childrens[i].style.left = childrens[i].style.left == "" ? "0px" : childrens[i].style.left;
}
initX = e.clientX;
initY = e.clientY;
document.onmouseup = closeDragElement;
document.onmousemove = elementDrag;
}
function elementDrag(e) {
if (flag) {
flag = false;
e = e || window.event;
deltaX = e.clientX - initX;
deltaY = e.clientY - initY;
for (var i = 0; i < childrens.length; i++) {
childrens[i].style.top = parseInt(childrens[i].style.top) + deltaY + "px";
childrens[i].style.left = parseInt(childrens[i].style.left) + deltaX + "px";
}
initX = e.clientX;
initY = e.clientY;
flag = true;
}
}
function closeDragElement() {
document.onmouseup = null;
document.onmousemove = null;
}
}
#mydiv {
position: fixed;
z-index: 9;
background-color: #f1f1f1;
text-align: center;
width: 400px;
height: 400px;
border: 1px solid #d3d3d3;
}
.child {
position: relative;
padding: 10px;
cursor: move;
z-index: 10;
background-color: #2196F3;
color: #fff;
}
<h1>Draggable DIV Element</h1>
<p>Click and hold the mouse button down while moving the DIV element</p>
<div id="mydiv" style="background-color:blue">
<p class="child" style="background-color:red">Move 1</p>
<p class="child" style="background-color:yellow">Move 2</p>
</div>
This isn't a nice solution but it works. Consider using jQuery and jQuery Draggable.

javascript for draw rectangle over a image

I was doing a project on php with java script.I was try to draw a rectangle over a image using javascript.The rectangle can draw any where of the image with any size as compare with image size and also display the co ordinate of drawing rectangle.Please any one help me...I was tried different ways.....
<STYLE>
#rubberBand {
position: absolute;
visibility: hidden;
width: 0px; height: 0px;
border: 2px solid red;
}
</STYLE>
</HEAD>
<BODY>
<img name="myImage" id="myImage" src="a.jpg">
<DIV ID="rubberBand"></DIV>
<SCRIPT>
var IMG;
function startRubber (evt) {
if (document.all) {
var r = document.all.rubberBand;
r.style.width = 0;
r.style.height = 0;
r.style.pixelLeft = event.x;
r.style.pixelTop = event.y;
r.style.visibility = 'visible';
IMG.ondragstart = cancelDragDrop; // otherwise IE will try to drag the image
}
else if (document.getElementById) {
// firefox
evt.preventDefault();
var r = document.getElementById('rubberBand');
r.style.width = 0;
r.style.height = 0;
r.style.left = evt.clientX + 'px';
r.style.top = evt.clientY + 'px';
r.style.visibility = 'visible';
r.onmouseup = stopRubber;
}
IMG.onmousemove = moveRubber;
}
function moveRubber (evt) {
if (document.all) { // IE
var r = document.all.rubberBand;
r.style.width = event.x - r.style.pixelLeft;
r.style.height = event.y - r.style.pixelTop;
}
else if (document.getElementById) { // firefox
var r = document.getElementById('rubberBand');
r.style.width = evt.clientX - parseInt(r.style.left);
r.style.height = evt.clientY - parseInt(r.style.top);
}
return false; // otherwise IE won't fire mouseup :/
}
function stopRubber (evt) {
IMG.onmousemove = null;
}
function cancelDragDrop()
{
window.event.returnValue = false;
}
IMG = document.getElementById('myImage');
IMG.onmousedown = startRubber;
IMG.onmouseup = stopRubber;
</SCRIPT>

You need a wrapper so you can absolutely-position elements inside. The dimensions will vary, depending on your photo and where you want the box.
HTML:
<div class="wrapper">
<img src="...." />
<div class="box"></div>
</div>
CSS:
.wrapper {
position:relative;
}
.box {
position:absolute;
top:10px;
left:10px;
width:50px;
height:50px;
border:2px solid #ffffff;
background-color:transparent
}