[Unity插件]Lua行为树(九)：条件节点调整

先看一下之前的条件节点是怎么设计的：

BTConditional.lua

 BTConditional = BTTask:New();
 
 local this = BTConditional;
 this.taskType = BTTaskType.Conditional;
 
 function this:New()
     local o = {};
     setmetatable(o, self);
     self.__index = self;
     return o;
 end

BTIsNullOrEmpty.lua

 --[[
 参考BehaviorDesigner-Conditional-IsNullOrEmpty
 --]]
 BTIsNullOrEmpty = BTConditional:New();
 
 local this = BTIsNullOrEmpty;
 this.name = "BTIsNullOrEmpty";
 
 function this:New(text)
     local o = {};
     setmetatable(o, self);
     self.__index = self;
     o.text = text;
     return o;
 end
 
 function this:OnUpdate()
     if (not self.text or self.text == "") then
         return BTTaskStatus.Success;
     else
         return BTTaskStatus.Failure;
     end
 end

由上可见，条件节点就是判断条件然后返回成功或者失败，而且也只会有这两种状态，这和if的逻辑是一样的，因此可以改进一下。

BTConditional.lua

 BTConditional = BTTask:New();
 
 local this = BTConditional;
 this.taskType = BTTaskType.Conditional;
 
 function this:New()
     local o = {};
     setmetatable(o, self);
     self.__index = self;
     return o;
 end
 
 function this:OnUpdate()
     if (self:Check()) then
         return BTTaskStatus.Success;
     else
         return BTTaskStatus.Failure;
     end
 end
 
 function this:Check()
     return false;
 end

BTIsNullOrEmpty.lua

 --[[
 参考BehaviorDesigner-Conditional-IsNullOrEmpty
 --]]
 BTIsNullOrEmpty = BTConditional:New();
 
 local this = BTIsNullOrEmpty;
 this.name = "BTIsNullOrEmpty";
 
 function this:New(text)
     local o = {};
     setmetatable(o, self);
     self.__index = self;
     o.text = text;
     return o;
 end
 
 function this:Check()
     if (not self.text or self.text == "") then
         return true;
     else
         return false;
     end
 end

TestBehaviorTree.lua

 TestBehaviorTree = BTBehaviorTree:New();
 
 local this = TestBehaviorTree;
 this.name = "TestBehaviorTree";
 
 function this:New()
     local o = {};
     setmetatable(o, self);
     self.__index = self;
     o:Init();
     return o;
 end
 
 function this:Init()
     local sequence = BTSequence:New();
     local isNullOrEmpty = BTIsNullOrEmpty:New();
     local log = BTLog:New("This is log!!!");
     log.name = "log";
 
     self:SetStartTask(sequence);
 
     sequence:AddChild(isNullOrEmpty);
     sequence:AddChild(log);
 end

打印如下：