<html>
...
<body>
<a-scene>
<a-sky color="#6EBAA7"></a-sky>
<a-plane id="screen" position="0 1.25 -1" color="red" scale="3 3 3" canvas-material="width:500;height:500"/>
</a-scene>
</body>
<script>
var component = document.querySelector("#screen").components["canvas-material"];
var ctx = component.getContext()
function getRndColor() {
var r = 255*Math.random()|0,
g = 255*Math.random()|0,
b = 255*Math.random()|0;
return 'rgb(' + r + ',' + g + ',' + b + ')';
}
window.setInterval(function(){
ctx.clearRect(0,0,500,500);
ctx.fillStyle = getRndColor();
ctx.fillRect(Math.random()*500,Math.random()*500,50,50);
ctx.fillStyle = "black";
ctx.font = "100px serif";
ctx.fillText("Hello world", 10, 100);
component.updateTexture();
},100)
</script>
</html>
