[Unity插件]Lua行为树(十三)：装饰节点完善

之前介绍了组合节点中三大常用的节点：BTSequence、BTSelector和BTParallel，一般来说，这三种就够用了，可以满足很多的需求。

接下来可以完善一下装饰节点，增加几种新的节点。

1.BTInverter

--[[
结果取反：
1.子节点返回Running，则节点返回Running
2.子节点返回Success，则节点返回Failure
3.子节点返回Failure，则节点返回Success
--]]
BTInverter = BTDecorator:New();

local this = BTInverter;
this.name = "BTInverter";

function this:New()
    local o = {};
    setmetatable(o, self);
    self.__index = self;
    o.childTasks = {};
    return o;
end

function this:OnUpdate()
    if (not self.currentChildTask) then
        self.currentChildTask = self:GetChild();
        if (not self.currentChildTask) then
            return BTTaskStatus.Failure;
        end
    end

    self.executionStatus = self.currentChildTask:OnUpdate();

    if (self.executionStatus == BTTaskStatus.Running) then
        return BTTaskStatus.Running;
    elseif (self.executionStatus == BTTaskStatus.Success) then
        return BTTaskStatus.Failure;
    else
        return BTTaskStatus.Success;
    end
end

function this:Reset()
    self.executionStatus = BTTaskStatus.Inactive;
    BTParentTask.Reset(self);
end

测试：

TestBehaviorTree2 = BTBehaviorTree:New();

local this = TestBehaviorTree2;
this.name = "TestBehaviorTree2";

function this:New()
    local o = {};
    setmetatable(o, self);
    self.__index = self;
    o:Init();
    return o;
end

function this:Init()
    local sequence = BTSequence:New();
    local inverter = BTInverter:New();
    local isNullOrEmpty = BTIsNullOrEmpty:New("123");
    local log = BTLog:New("This is a tree!!!");

    self:SetStartTask(sequence);

    inverter:AddChild(isNullOrEmpty);

    sequence:AddChild(inverter);
    sequence:AddChild(log);
end

输出：

2.BTReturnFailure

--[[
结果返回失败：
1.子节点返回Running，则节点返回Running
2.其余情况，则节点返回Failure
--]]
BTReturnFailure = BTDecorator:New();

local this = BTReturnFailure;
this.name = "BTReturnFailure";

function this:New()
    local o = {};
    setmetatable(o, self);
    self.__index = self;
    o.childTasks = {};
    return o;
end

function this:OnUpdate()
    if (not self.currentChildTask) then
        self.currentChildTask = self:GetChild();
        if (not self.currentChildTask) then
            return BTTaskStatus.Failure;
        end
    end

    self.executionStatus = self.currentChildTask:OnUpdate();

    if (self.executionStatus == BTTaskStatus.Running) then
        return BTTaskStatus.Running;
    else
        return BTTaskStatus.Failure;
    end
end

function this:Reset()
    self.executionStatus = BTTaskStatus.Inactive;
    BTParentTask.Reset(self);
end

测试：

TestBehaviorTree2 = BTBehaviorTree:New();

local this = TestBehaviorTree2;
this.name = "TestBehaviorTree2";

function this:New()
    local o = {};
    setmetatable(o, self);
    self.__index = self;
    o:Init();
    return o;
end

function this:Init()
    local selector = BTSelector:New();
    local returnFailure = BTReturnFailure:New();
    local isNullOrEmpty = BTIsNullOrEmpty:New();
    local log = BTLog:New("This is a tree!!!");

    self:SetStartTask(selector);

    returnFailure:AddChild(isNullOrEmpty);

    selector:AddChild(returnFailure);
    selector:AddChild(log);
end

输出：

3.BTUntilFailure

--[[
结果返回失败：
1.子节点返回Failure，则节点返回Failure
2.其余情况，则节点返回Running
--]]
BTUntilFailure = BTDecorator:New();

local this = BTUntilFailure;
this.name = "BTUntilFailure";

function this:New()
    local o = {};
    setmetatable(o, self);
    self.__index = self;
    o.childTasks = {};
    return o;
end

function this:OnUpdate()
    if (not self.currentChildTask) then
        self.currentChildTask = self:GetChild();
        if (not self.currentChildTask) then
            return BTTaskStatus.Failure;
        end
    end

    self.executionStatus = self.currentChildTask:OnUpdate();

    if (self.executionStatus ~= BTTaskStatus.Failure) then
        return BTTaskStatus.Running;
    else
        return BTTaskStatus.Failure;
    end
end

function this:Reset()
    self.executionStatus = BTTaskStatus.Inactive;
    BTParentTask.Reset(self);
end

测试：

TestBehaviorTree2 = BTBehaviorTree:New();

local this = TestBehaviorTree2;
this.name = "TestBehaviorTree2";

function this:New()
    local o = {};
    setmetatable(o, self);
    self.__index = self;
    o:Init();
    return o;
end

function this:Init()
    local selector = BTSelector:New();
    local untilFailure = BTUntilFailure:New();
    local action = self:GetBTActionUniversal();
    local log = BTLog:New("This is a tree!!!");

    self:SetStartTask(selector);

    untilFailure:AddChild(action);

    selector:AddChild(untilFailure);
    selector:AddChild(log);
end

function this:GetBTActionUniversal()
    local count = 1;
    local a = function ()
        if (count == 1) then
            count = count + 1;
            print("11");
            return BTTaskStatus.Success;
        elseif (count == 2) then
            count = count + 1;
            print("22");
            return BTTaskStatus.Running;
        else
            print("33");
            return BTTaskStatus.Failure;
        end
    end
    local universal = BTActionUniversal:New(nil, a);
    return universal;
end

输出：

最后给出这个系列的源码：

https://pan.baidu.com/s/1QwjozJ3dEpqNRL04oLvfHw