just-animate/lib.es2015/lib/reducers/update.js

_Making Animation Simple_

import { loopOff } from '../core/timeloop';
import { S_PLAYING, _ } from '../utils/constants';
import { inRange, minMax, flr } from '../utils/math';
import { all } from '../utils/lists';
import { setup } from './setup';
import { UPDATE } from '../actions';
export const update = (model, _data, ctx) => {
    if (model.players === _) {
        setup(model);
    }
    const isPlaying = model.state === S_PLAYING;
    const time = model.time;
    if (!isPlaying) {
        loopOff(model.id);
    }
    all(model.players, player => {
        const from = player.from;
        const to = player.to;
        const isActive = isPlaying && inRange(flr(time), from, to);
        const offset = minMax((time - from) / (to - from), 0, 1);
        player.update(offset, model.rate, isActive);
    });
    ctx.trigger(UPDATE);
};