When drawing two buttons on a canvas using rectangles and text overlaid, I encountered different results even though the same loop was used. One "button" had the text hidden behind the box while the other had the text displayed on top. I am curious about why this happened and how sorting works in canvas.
<body>
<canvas id="canvas" width="320" height="512"
style="position: absolute; left: 500px; top: 50px; z-index: 1;"></canvas>
<script>
var canvas = document.getElementById('canvas');
var context = canvas.getContext("2d");
canvas.style.backgroundColor = 'rgba(0, 0, 0, 0)';
context.clearRect(0, 0, 320, 16);
gameMenu();
function gameMenu(){
var buttons = [ {x: 210, y: 420, w: 80, h: 30, s: "Messages"},
{x: 210, y: 470, w: 80, h: 30, s: "Pause"} ], i = 0, r;
while(r = buttons[i++]) {
context.rect(r.x, r.y, r.w, r.h);
context.fillStyle = "rgb(26,26,26)";
context.fill();
context.fillStyle = 'White';
context.font = "16px Tahoma";
context.fillText(r.s, r.x + 18, r.y + 22);
}
}
</script>
</body>
To see the issue in action, check out this JS Fiddle link: https://jsfiddle.net/oa84Lsxn/1/