FPS_COUNT_AMOUNT :: 30;
average_fps: int;
fps_counts: [FPS_COUNT_AMOUNT] int;
fps_count_cursor: int;

update_fps_counter :: (dt: float) {
    fps_counts[fps_count_cursor] = cast(int)(1.0/dt);
    fps_count_cursor += 1;
    if fps_count_cursor == FPS_COUNT_AMOUNT {
        fps_count_cursor = 0;
    }

    total_fps : int;
    for 0..FPS_COUNT_AMOUNT-1 {
        total_fps += fps_counts[it];
    }

    average_fps = total_fps / FPS_COUNT_AMOUNT;
}