WebGLでHELLOと表示するためなら手段を選ばないコード。

hellowebgl.html

<canvas></canvas>
<script>
const hello=`
#...#.#####.#####.#####..###..
#...#.#.....#.....#.....#...#.
#####.####..#.....#.....#...#.
#...#.#.....#.....#.....#...#.
#...#.#####.#.....#......###..`;
let cx=document.querySelector("canvas").getContext("webgl");
cx.clearColor(0,0.3,0,1);	cx.clear(0x4000);
cx.pixelStorei(cx.UNPACK_FLIP_Y_WEBGL,true);
cx.enable(cx.SCISSOR_TEST);
for(let i=0; i<31; i++)for(let j=0; j<8; j++){
	if(hello.charAt(j*31+i)=="#"){
		rect(i*4,j*4+8,6,4);
	}
}
function rect(x,y, w=1, h=1){
	cx.scissor(x,y, w,h);	cx.clearColor(1,1,0,1);	cx.clear(0x4000);
}
</script>