JSFiddle - React, Tailwind, and code Playground

HTML

<div class="image-rectangle">
    <img alt="" src="http://cs304605.vk.me/v304605289/3ff9/s4rpaW_TZ6A.jpg">
</div>

CSS

.image-point {
    background: red;
    height: 3px;
    position: absolute;
    width: 3px;
}
.image-rectangle {
    display: inline-block;
    position: relative;
}

JavaScript

var imageRectangle = document.querySelector('.image-rectangle');

function imageSetPoint(x, y) {
    var point = document.createElement('div');
    point.className = 'image-point';
    point.style.left = x + 'px';
    point.style.top = y + 'px';
    imageRectangle.appendChild(point);
};

imageSetPoint(100, 100);
imageSetPoint(150, 150);
imageSetPoint(200, 200);