jjb-lc-designable/shared/animation.js

基于alibaba-designable源码二次封装的表单设计器。

export const createUniformSpeedAnimation = (speed = 10, callback) => {
  let request = null;
  let startTime = null;
  const start = () => {
    if (request) return;
    request = requestAnimationFrame(timestamp => {
      if (startTime === null) {
        startTime = timestamp;
      }
      const deltaTime = timestamp - startTime;
      const delta = deltaTime / 1000 * speed;
      callback(delta);
      request = null;
      start();
    });
  };
  start();
  return () => {
    if (request) {
      cancelAnimationFrame(request);
      request = null;
    }
    startTime = null;
  };
};

//越接近阈值，速度越小，越远离阈值，速度越大
export const calcSpeedFactor = (delta = 0, threshold = Infinity) => {
  if (threshold >= delta) {
    return (threshold - delta) / threshold;
  }
  return 0;
};