Attempting to place a canvas inside a div named touch-container, with 3 additional divs on top and sizing them using javascript.
The issue arises as each of the 3 divs appear to have a margin that fills up the remaining space in the container, despite specifying a margin of 0.
Click here for jsFiddle preview, inspect to see the mysterious margin: Jsfiddle
HTML:
<div id = "touch-container">
<div id = "touch-left" class = "touch-control"></div>
<div id = "touch-middle" class = "touch-control"></div>
<div id = "touch-right" class = "touch-control"></div>
<canvas id = "canvas" width = "960" height = "560"></canvas>
</div>
CSS:
body {
margin: 0;
}
#touch-container{
width: 964px;
height: 560px;
display: inline-block;
margin: 0;
}
.touch-control{
position: relative;
margin: 0;
}
#touch-left{
background-color: red;
}
#touch-middle{
background-color: green;
}
#touch-right{
background-color: blue;
}
JS:
var leftTouch = document.getElementById('touch-left');
var upTouch = document.getElementById('touch-middle');
var rightTouch = document.getElementById('touch-right');
var canvas = document.getElementById('canvas');
var ctx = canvas.getContext("2d");
var width = (canvas.width > canvas.height ? canvas.width : canvas.height);
var height = (canvas.height > canvas.width ? canvas.width : canvas.height);
leftTouch.style.width = (width/ 4) + 'px';
leftTouch.style.height = height + 'px';
upTouch.style.width = (width/ 2) + 'px';
upTouch.style.height = height + 'px';
rightTouch.style.width = (width/ 4) + 'px';
rightTouch.style.height = height + 'px';
ctx.fillRect(0,0,canvas.width, canvas.height);
The colored squares should make a black square at the bottom, followed by red, green, and blue squares from left to right occupying 25%, 50% 25% of the container, rendering the black canvas invisible.