久久婷婷五月综合成人D啪 ,少妇久久久久久久久久,国产激情久久久久影院小草

(搬運工)基于Lua的State Pattern

Posted on 2012-05-07 13:58 點點滴滴閱讀(431) 評論(0) 編輯收藏引用

class.lua實現(xiàn)了在Lua中創(chuàng)建類的模擬，非常方便。class.lua參考自http://lua-users.org/wiki/SimpleLuaClasses

1
-- class.lua 

2
-- Compatible with Lua 5.1 (not 5.0). 

3

4
function class(base, init) 

5
local c = {} -- a new class instance 

6
if not init and type(base) == 'function' then

7
init = base 

8
base = nil

9
elseif type(base) == 'table' then

10
-- our new class is a shallow copy of the base class! 

11
for i,v in pairs(base) do

12
c[i] = v 

13
end

14
c._base = base 

15
end

16
-- the class will be the metatable for all its objects, 

17
-- and they will look up their methods in it. 

18
c.__index = c 

19

20
-- expose a constructor which can be called by <classname>(<args>) 

21
local mt = {} 

22
mt.__call = function(class_tbl, ...) 

23
local obj = {} 

24
setmetatable(obj,c) 

25

26
-- below 2 lines are updated based on the Comments from 'http://lua-users.org/wiki/SimpleLuaClasses' 

27
-- if init then 

28
-- init(obj,...) 

29
if class_tbl.init then

30
class_tbl.init(obj,...) 

31
else

32
-- make sure that any stuff from the base class is initialized! 

33
if base and base.init then

34
base.init(obj, ...) 

35
end

36
end

37
return obj 

38
end

39
c.init = init 

40
c.is_a = function(self, klass) 

41
local m = getmetatable(self) 

42
while m do

43
if m == klass then return true end

44
m = m._base 

45
end

46
return false 

47
end

48
setmetatable(c, mt) 

49
return c 

50
end

State基類，包含三個stub函數(shù)，enter()和exit()分別在進(jìn)入和退出state時被執(zhí)行，onUpdate()函數(shù)將會在state被激活時的每幀被執(zhí)行。

1
require "class"

2

3
State = class() 

4

5
function State:init( name ) 

6
self.name = name 

7
end

8

9
function State:enter() 

10
end

11

12
function State:onUpdate() 

13
end

14

15
function State:exit() 

16
end

StateMachine類，該類集成了Moai的MOAIThread類。MOAIThread類似于Lua中的coroutine，但是在Moai中被yield的MOAIThread，會在game loop的每幀中被自動resume，見StateMachine:updateState函數(shù)，利用此特點，來實現(xiàn)每幀執(zhí)行State:onUpdate函數(shù)。

1
require "State"

2

3
StateMachine = class() 

4

5
function StateMachine:init() 

6
self.currentState = nil

7
self.lastState = nil

8
end

9

10
function StateMachine:run() 

11
if ( self.mainThread == nil ) 

12
then

13
self.mainThread = MOAIThread.new() 

14
self.mainThread:run( self.updateState, self ) 

15
end

16
end

17

18
function StateMachine:stop() 

19
if ( self.mainThread ) 

20
then

21
self.mainThread:stop() 

22
end

23
end

24

25
function StateMachine:setCurrentState( state ) 

26
if ( state and state:is_a( State ) ) 

27
then

28
if ( state == self.currentState ) 

29
then

30
print( "WARNING @ StateMachine::setCurrentState - " .. 

31
"var state [" .. state.name .. "] is the same as current state" ) 

32
return

33
end

34
self.lastState = self.currentState 

35
self.currentState = state 

36
if ( self.lastState ) 

37
then

38
print( "exiting state [" .. self.lastState.name .. "]" ) 

39
self.lastState:exit() 

40
end

41
print( "entering state [" .. self.currentState.name .. "]" ) 

42
self.currentState:enter() 

43
else

44
print( "ERROR @ StateMachine::setCurrentState - " .. 

45
"var [state] is not a class type of State" ) 

46
end

47
end

48

49
function StateMachine:updateState() 

50
while ( true ) 

51
do

52
if ( self.currentState ~= nil ) 

53
then

54
self.currentState:onUpdate() 

55
end

56
coroutine.yield() 

57
end

58
end

如何利用State和StateMachine類的示例，首先定義兩個state。
SampleState.lua

1
require "State"

2

3
State1 = class( State ) 

4

5
function State1:init() 

6
State.init( self, "State1" ) 

7
end

8

9
function State1:enter() 

10
self.i = 0 

11
end

12

13
function State1:exit() 

14
self.i = 0 

15
end

16

17
function State1:onUpdate() 

18
print( self.name .. " is updated" ) 

19
self.i = self.i + 1 

20
print( "self.i=" .. self.i ) 

21
if ( self.i == 10 ) 

22
then

23
print( state2 ) 

24
SM:setCurrentState( state2 ) 

25
self.i = 0 

26
end

27
end

28

29
----------------------- 

30

31
State2 = class( State ) 

32

33
function State2:init() 

34
State.init( self, "State2" ) 

35
end

36

37
function State2:onUpdate() 

38
print( "State2 is updated" ) 

39
end

test.lua

1
require "StateMachine"

2
require "SampleState"

3

4
SM = StateMachine() 

5
SM:run() 

6
state1 = State1() 

7
state2 = State2() 

8
SM:setCurrentState( state1 )

點點滴滴

(搬運工)基于Lua的State Pattern

日歷

公告

留言簿(9)

隨筆分類(268)

隨筆檔案(311)

相冊

搜索

積分與排名

最新評論