animate-value/es/lib/tick.js

🏃 animates a numeric value

import calcStartEnd from './calc/calcStartEnd';
import calcProgress from './calc/calcProgress';

import now from './time/now';

var tick = function tick(data, label, resolve) {
  var _data = data,
      start = _data.start,
      end = _data.end,
      easing = _data.easing,
      to = _data.to,
      from = _data.from,
      duration = _data.duration,
      change = _data.change,
      done = _data.done,
      loop = _data.loop,
      rewind = _data.rewind,
      loopDelay = _data.loopDelay;


  if (start && end) {

    var prog = calcProgress(start, duration, easing);
    data.value = from + (to - from) * prog;

    if (now() <= end) {

      if (change && now() >= start) change(data.value);

      label = requestAnimationFrame(function () {
        return tick(data, label, resolve);
      });
    } else {

      if (change) change(data.to);

      if (loop) {

        if (rewind) {
          var _data2 = data,
              _from = _data2.from,
              _to = _data2.to;


          data.from = _to;
          data.to = _from;
        }

        var _delay = loopDelay;

        data = Object.assign({}, data, calcStartEnd(_delay, duration));

        if (data.iteration) {

          data.iteration += 1;

          var _data3 = data,
              _iteration = _data3.iteration;


          if (rewind) _iteration = _iteration / 2;

          if (loop === true || _iteration <= loop) {
            label = requestAnimationFrame(function () {
              return tick(data, label, resolve);
            });
          } else {
            if (done) done();
            resolve();
          }
        }
      } else {
        if (done) done();
      }
    }
  }
};

export default tick;