object Pool {

    private val tmp = List(10) {
        Transmitter()
    }

    val objects = List(40) {
        when {
            it < 10 -> Colored(Region.rndColorName(), Shell(), Direction.DOWN).also { it.isVisible = false }
            it < 30 -> Arrow(Name.ARROW, Shell(), Direction.DOWN).also { it.isVisible = false }
            else -> Bomb(Name.BOMB, Shell(), Direction.DOWN).also { it.isVisible = false }
        }
    }

    fun add(name: Name, shell: Shell, direction: Direction) {
        for (id in tmp.indices) {
            if (tmp[id].name == null) {
                tmp[id].name = name
                tmp[id].shell = shell
                tmp[id].direction = direction
                Transmitter.counter++
                break
            }
        }
    }

    //  objects должен содержать только один класс, так как Colored,Arrow,Bomb в objects не имеют значения.
    //  проход завершается если в tmp закончились объекты tmp[N].var == null
    fun update() {
        var tmpId = 0
        for (id in objects.indices) {
            if (Transmitter.counter == 0) {
                println(id)
                break
            }
            if (!objects[id].isVisible) {
                if (tmp[tmpId].name == null || tmpId >= tmp.size - 1) {
                    clearTmp()
                    return
                } else {
                    objects[id].reuse(
                            tmp[tmpId].name!!,
                            tmp[tmpId].shell!!,
                            tmp[tmpId].direction!!
                    )
                    tmpId++
                    Transmitter.counter--
                }
            }
        }
        clearTmp()
    }

    //  проход завершается как будет найден последний объект из tmp в objects по имени
    //  tmp постоянно прогоняется полностью
    fun update2() {
        for (id in objects.indices) {
            if (Transmitter.counter == 0) {
                println(id)
                break
            }
            if (!objects[id].isVisible) {
                for (i in tmp.indices) {
                    if (objects[id].name == tmp[i].name) {
                        objects[id].reuse(
                                tmp[i].name!!,
                                tmp[i].shell!!,
                                tmp[i].direction!!
                        )
                        tmp[i].name = null
                        tmp[i].shell = null
                        tmp[i].direction = null
                        Transmitter.counter--
                        break
                    }
                }
            }
        }
        clearTmp()
    }

    private fun clearTmp() {
        for (id in tmp.indices) {
            tmp[id].name = null
            tmp[id].shell = null
            tmp[id].direction = null
        }
        Transmitter.counter = 0
    }
}

class Transmitter {
    var name: Name? = null
    var shell: Shell? = null
    var direction: Direction? = null

    companion object {
        var counter = 0
    }
}

fun test() {

    Pool.add(Name.RED, Shell(), Direction.LEFT)
    Pool.add(Name.ARROW, Shell(), Direction.MISSING)
    Pool.add(Name.BOMB, Shell(), Direction.UP)
//    Pool.update()   //  всего 3 прохода, так как нужное находится при первом name == null
    Pool.update2()  //  30 проходов, так как BOMB встречается на позиции 30 в objects

    var isVisible = 0
    for (o in Pool.objects) {
        if (o.isVisible) isVisible++
        println("ID = ${o.id}, Name: ${o.name}, ${o.isVisible}")
    }
    println("В пул добавлены $isVisible объекта")
}

//------------------------------------------------------------------------------------------------------------------
results:
update()
3 прохода objects (первые 3 ячейки из objects )
ID = 16, Name: RED, true
ID = 17, Name: ARROW, true
ID = 18, Name: BOMB, true
ID = 19, Name: GREEN, false
ID = 20, Name: RED, false
ID = 21, Name: GREEN, false
ID = 22, Name: BLUE, false
ID = 23, Name: YELLOW, false
ID = 24, Name: LIGHT_BLUE, false
ID = 25, Name: LIGHT_BLUE, false
ID = 26, Name: ARROW, false
ID = 27, Name: ARROW, false
ID = 28, Name: ARROW, false
ID = 29, Name: ARROW, false
ID = 30, Name: ARROW, false
ID = 31, Name: ARROW, false
ID = 32, Name: ARROW, false
ID = 33, Name: ARROW, false
ID = 34, Name: ARROW, false
ID = 35, Name: ARROW, false
ID = 36, Name: ARROW, false
ID = 37, Name: ARROW, false
ID = 38, Name: ARROW, false
ID = 39, Name: ARROW, false
ID = 40, Name: ARROW, false
ID = 41, Name: ARROW, false
ID = 42, Name: ARROW, false
ID = 43, Name: ARROW, false
ID = 44, Name: ARROW, false
ID = 45, Name: ARROW, false
ID = 46, Name: BOMB, false
ID = 47, Name: BOMB, false
ID = 48, Name: BOMB, false
ID = 49, Name: BOMB, false
ID = 50, Name: BOMB, false
ID = 51, Name: BOMB, false
ID = 52, Name: BOMB, false
ID = 53, Name: BOMB, false
ID = 54, Name: BOMB, false
ID = 55, Name: BOMB, false
В пул добавлены 3 объекта

update2()
31 проход objects (первый найденый: RED = 18, ARROW = 26, BOMB = 46 )
ID = 16, Name: YELLOW, false
ID = 17, Name: LIGHT_BLUE, false
ID = 18, Name: RED, true
ID = 19, Name: ORANGE, false
ID = 20, Name: ORANGE, false
ID = 21, Name: PURPLE, false
ID = 22, Name: PURPLE, false
ID = 23, Name: PURPLE, false
ID = 24, Name: BLUE, false
ID = 25, Name: ORANGE, false
ID = 26, Name: ARROW, true
ID = 27, Name: ARROW, false
ID = 28, Name: ARROW, false
ID = 29, Name: ARROW, false
ID = 30, Name: ARROW, false
ID = 31, Name: ARROW, false
ID = 32, Name: ARROW, false
ID = 33, Name: ARROW, false
ID = 34, Name: ARROW, false
ID = 35, Name: ARROW, false
ID = 36, Name: ARROW, false
ID = 37, Name: ARROW, false
ID = 38, Name: ARROW, false
ID = 39, Name: ARROW, false
ID = 40, Name: ARROW, false
ID = 41, Name: ARROW, false
ID = 42, Name: ARROW, false
ID = 43, Name: ARROW, false
ID = 44, Name: ARROW, false
ID = 45, Name: ARROW, false
ID = 46, Name: BOMB, true
ID = 47, Name: BOMB, false
ID = 48, Name: BOMB, false
ID = 49, Name: BOMB, false
ID = 50, Name: BOMB, false
ID = 51, Name: BOMB, false
ID = 52, Name: BOMB, false
ID = 53, Name: BOMB, false
ID = 54, Name: BOMB, false
ID = 55, Name: BOMB, false
В пул добавлены 3 объекта