[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：