Lua中使用状态机FSM简单例子

时间:2022-05-16 07:55:58

FSM 有限状态机:

一个有限状态机是一个设备,或者是一个设备模型,具有有限数量的状态,它可以在任何给定的时间根据输入进行操作,使得一个状态变换到另一个状态,或者是使一个输入或者一种行为的发生。一个有限状态机在任何瞬间只能处在一种状态。

进入动作

退出动作

更新动作

FsmMachine.lua

FsmMachine = {}

function FsmMachine:New()
self.__index = self
o = setmetatable({}, self)
o.states = {}
o.curState = nil
return o
end -- 添加状态
function FsmMachine:AddState(baseState)
self.states[baseState.stateName] = baseState
end -- 初始化默认状态
function FsmMachine:AddInitState(baseState)
self.curState = baseState
end -- 更新当前状态
function FsmMachine:Update()
self.curState:OnUpdate()
end -- 切换状态
function FsmMachine:Switch(stateName)
if self.curState.stateName ~= stateName then
self.curState:OnLeave()
self.curState = self.states[stateName]
self.curState:OnEnter()
end
end

状态机基类

BaseState.lua

BaseState = {}

function BaseState:New(stateName)
self.__index = self
o = setmetatable({}, self)
o.stateName = stateName
return o
end -- 进入状态
function BaseState:OnEnter()
end -- 更新状态
function BaseState:OnUpdate()
end -- 离开状态
function BaseState:OnLeave()
end

测试类

Main.lua

require("BaseState")
require("FsmMachine")
FsmMachineTest = {} -----[状态A,覆盖BaseState方法]----------------
aState = BaseState:New("aState") function aState:OnEnter()
print("aState:OnEnter()")
end function aState:OnUpdate()
print("aState:OnUpdate()")
end function aState:OnLeave()
print("aState:OnLeave()")
end -----[状态B,覆盖BaseState方法]----------------
bState = BaseState:New("bState") function bState:OnEnter()
print("bState:OnEnter()")
end function bState:OnUpdate()
print("bState:OnUpdate()")
end function bState:OnLeave()
print("bState:OnLeave()")
end -----[测试状态机]-----------------------------
fsm = FsmMachine:New()
fsm:AddState(aState)
fsm:AddState(bState)
fsm:AddInitState(aState) for i = 1, 10 do
if i == 5 then
fsm:Switch("bState")
end
fsm.curState:OnUpdate()
end

输出

aState:OnUpdate()
aState:OnUpdate()
aState:OnUpdate()
aState:OnUpdate()
aState:OnUpdate()
aState:OnLeave()
bState:OnEnter()
bState:OnUpdate()
bState:OnUpdate()
bState:OnUpdate()
bState:OnUpdate()
bState:OnUpdate()