如何用JavaScript贝塞尔曲线实现数字分段增长动画？

// 贝塞尔曲线控制点
const startX = 0;
const startY = 0;
const cp1X = 0.1;
const cp1Y = 0.4;
const cp2X = 0.9;
const cp2Y = 0.6; //调整此值可以改变动画曲线
const endX = 1;
const endY = 1;

// 计算贝塞尔曲线 y 坐标
function bezier(t) {
  const cx = 3 * (cp1X - startX);
  const cy = 3 * (cp1Y - startY);
  const bx = 3 * (cp2X - cp1X) - cx;
  const by = 3 * (cp2Y - cp1Y) - cy;
  const ax = endX - startX - cx - bx;
  const ay = endY - startY - cy - by;
  const x = ax * t * t * t + bx * t * t + cx * t + startX;
  const y = ay * t * t * t + by * t * t + cy * t + startY;
  return y;
}

// 动画参数
let count = 0;
const target = 1000;
const duration = 3000; // 动画时长 (毫秒)
const startTime = null;
const displayElement = document.getElementById('display'); // 获取显示数字的元素

function update() {
  if (startTime === null) startTime = Date.now();
  const elapsed = Date.now() - startTime;
  const t = Math.min(1, elapsed / duration);
  count = Math.floor(bezier(t) * target); // 使用贝塞尔曲线计算当前值
  displayElement.textContent = count; // 更新显示

  if (elapsed < duration) {
    requestAnimationFrame(update);
  }
}

update(); // 开始动画