<canvas width="600" height="500"></canvas>
<script>
function desenhaEsquadro(xa, ya, xc, yc, cor) {
pincel.fillStyle = "black";
pincel.fillRect(0, 0, 600, 500);
pincel.fillStyle = cor;
pincel.beginPath();
pincel.moveTo(xa, ya);
pincel.lineTo(xa, yc);
pincel.lineTo(xc, yc);
pincel.fill();
pincel.fillStyle = "black";
pincel.beginPath();
pincel.moveTo(xa + 50, ya + 125);
pincel.lineTo(xa + 50, yc - 50);
pincel.lineTo(xc - 125, yc - 50);
pincel.fill();
}
var tela = document.querySelector('canvas');
var pincel = tela.getContext('2d');
desenhaEsquadro(50, 50, 400, 400, '#7CFC00');
</script>
)
