static enum uint TICK_MS = 50;
static enum int MOVE_PER_TICK = 1;

enum
{
    MOVE_LEFT,
    MOVE_RIGHT,
    MOVE_UP,
    MOVE_DOWN
}

struct Player
{
    int x;
    int y;
};

struct MoveEvent
{
    int type;
    bool active;
    uint tick;
};

class Game
{
public:
    void change_player()
    {
        m_pindex ^= 1;
    }
    void handle_move_event(int type, bool active)
    {
        final switch (type)
        {
        case MOVE_LEFT:
            m_left = active;
            break;
        case MOVE_RIGHT:
            m_right = active;
            break;
        case MOVE_UP:
            m_up = active;
            break;
        case MOVE_DOWN:
            m_down = active;
            break;
        }
    }
    void update(uint ms)
    {
        while (ms > (m_last_tick_ms + TICK_MS))
        {
            if (m_left)
                m_players[m_pindex].x -= MOVE_PER_TICK;
            if (m_right)
                m_players[m_pindex].x += MOVE_PER_TICK;
            if (m_up)
                m_players[m_pindex].y += MOVE_PER_TICK;
            if (m_down)
                m_players[m_pindex].y -= MOVE_PER_TICK;
            m_last_tick_ms += TICK_MS;
            m_tick++;
        }
    }
    Player[] get_players() { return m_players; }
protected:
    bool m_left;
    bool m_right;
    bool m_up;
    bool m_down;
    uint m_tick;
    uint m_last_tick_ms;
    Player[2] m_players;
    int m_pindex;
};