simple timer to put on the game loop to avoid using setTimeout.

tinyTimer.js

const tinyTimer = (function () {
    const timers = []
    function update() {
        const time = performance.now()
        let i = 0
        while (i < timers.length) {
            let timer = timers[i]
            if (time > timer.start + timer.duration) {
                timer.callback()
                timers.splice(i, 1)
            } else {
                i++
            }
        }
    }
    return {
        timers: timers,
        update: update
    }
})()

function wait(duration, callback) {
    tinyTimer.timers.push({
        duration: duration,
        start: performance.now(),
        callback: callback,
    })
}