{
const ctx = DOM.context2d();
ctx.canvas.width = width;
ctx.canvas.height = height;
ctx.strokeStyle = 'coral';
ctx.beginPath();
ctx.arc(cpx1, cpyAnim1, 5, 0, 2 * Math.PI);
ctx.stroke();
ctx.beginPath();
ctx.arc(cpx2, cpyAnim2, 5, 0, 2 * Math.PI);
ctx.stroke();
ctx.beginPath();
ctx.moveTo(0, height);
ctx.lineTo(0, y);
ctx.quadraticCurveTo(cpx1, cpyAnim1, endX1, y);
ctx.quadraticCurveTo(cpx2, cpyAnim2, endX2, y);
ctx.lineTo(width, height);
ctx.closePath();
ctx.clip();
ctx.fillStyle = 'skyblue';
ctx.fillRect(0, 0, width, height);
ctx.strokeStyle = 'coral';
ctx.beginPath();
ctx.arc(cpx1, cpyAnim1, 5, 0, 2 * Math.PI);
ctx.stroke();
ctx.beginPath();
ctx.arc(cpx2, cpyAnim2, 5, 0, 2 * Math.PI);
ctx.stroke();
return ctx.canvas;
}