createCanvas(600,400);

    translate(width/2 - 150, 0);

    beginShape();

    fill(100);

    vertex(0, 100);

    // First point sets the curve

    // Must have at least 4 points

    curveVertex(150, 600);

    curveVertex(0, 100);

    curveVertex(150, 100);

    curveVertex(300, 100);

    // And last point sets the curve

    curveVertex(150, 600);

    vertex(0, 100);

    endShape();

}