我认为通常***跟踪剩余时间.递减计数变量使用递减计数的持续时间初始化.通过简单地增加或减去剩余时间，可以(在游戏中)轻松实现延长倒数计时的奖金和减少倒数的罚款.跟踪倒计时到期的实际"时间(使用timer + duration或类似方法)通常没有什么用，特别是在您的游戏可以暂停的情况下.可能会产生不良后果，因此您必须编写代码.

I think it's generally best to track time-remaining. The count-down variable is initialized with the duration of the count-down. This makes it easy (in a game) to implement bonuses that extend the count-down, and penalties that reduce it, by simply adding to or subrtacting from the time remaining. Tracking the "actual" time that the count-down expires (using timer + duration or something similar) is generally less useful, especially if your game can be paused. Undesired effects could occur that you would have to code around.

执行一个程序来初始化倒数计时.

Implement a procedure to initialize the count-down.

to setup-timer
   set count-down 30 ;; a 30 tick timer
   ;; if you have a display of the remaining time, 
   ;; you might want to initialize it here, for example:
   ask patch max-pxcor max-pycor
   [ set plabel-color white 
     set plabel count-down
   ]
end
;; this example is for global count-down.
;; for a per-agent count-down, each agent would need
;; to initialize its own count-down variable

执行一个减少剩余时间的过程.

Implement a procedure to decrement the remaining time.

to decrement-timer
   set count-down count-down - 1
end

执行一个程序来测试倒计时是否已过期.

Implement a procedure to test whether the count-down has expired.

to-report timer-expired?
   report ( count-down <= 0 )
end

实现一种显示剩余时间或经过时间的方法.例如:

Implement a way to display the time remaining or elapsed time. For example:

• 使用补丁标签显示时间:

• Use a patch label to show the time:

to update-timer-display
   ask patch max-pxcor max-pycor [ set plabel count-down ]
end

使用带有时钟形状的特殊定义的乌龟来显示时间流逝. NetLogo模型库中存在这样的示例

use a specially defined turtle with a clock shape to show the time elapsing. Examples of this exist in the NetLogo Models Library

实施计时器到期时发生的操作.

Implement the action that occurs when the timer expires.

• 这完全取决于您.

• This is entirely up to you.

这可能涉及重置计时器以进行另一次倒计时.

This may involve resetting the timer for another count-down.

要在程序中使用倒数计时器，您必须:

1. 在适当的地方初始化倒数计时器(例如游戏或一轮游戏开始时).

1. Initialise the count-down timer where appropriate (such as when the game, or a round of the game, begins).

更改并测试计时器.

• 这可能是打勾"一次，或者是基于实时的计算.

• This might be once per "tick", or a calulation based on real time.

1. 减少倒计时的递减计数.
2. 根据需要更新计时器的显示.
3. 测试计时器以查看其是否已过期.

4. 对到期的计时器执行操作.

1. Decrement the count-down on whatever shedule is appropriate.
2. Update the display of the timer, if desired.
3. Test the timer to see if it has expired.

4. Act on the expired timer.

;; a "once-per-tick" count-down
decrement-timer
update-timer-display
if timer-expired? [ act-on-expired-timer ]
;; rest of the go procedure, then... 
tick

;; a "once-per-second" count-down
every 1 ;; this block runs only once per second
[ decrement-timer
  update-timer-display
  if timer-expired? [ act-on-expired-timer ]
]
;; the rest of the go procedure
tick