[Unity插件]Lua行为树(六)：打印树结构

经过前面的文章，已经把行为树中的四种基本类型节点介绍了下。接下来可以整理一下，打印一下整棵行为树。注意点如下：

1.可以把BTBehaviorTree也当作一种节点，这样就可以方便地进行行为树嵌套了

2.可以在BTBehaviorTree中的SetStartTask、BTParentTask中的AddChild，即在设置节点和添加节点时对节点的信息进行打印

以下面这棵行为树为例：

BTTask.lua

 BTTask = {};

 local this = BTTask;

 function this:New()

     local o = {};

     setmetatable(o, self);

     self.__index = self;

     o.executionStatus = BTTaskStatus.Inactive;   --该节点的执行状态

     o.root = nil;                                 --根节点

     o.parent = nil;                               --父节点

     o.layer = ;                                 --第几层

     o.index = ;                                 --父节点下的第几个节点

     o.name = "BTTask";                           --该节点名字

     return o;

 end

 function this:ToString()

     local root = "root:";

     if (self.root) then

         root = root .. self.root.name;

     else

         root = root .. "nil";

     end

     local parent = "parent:";

     if (self.parent) then

         parent = parent .. self.parent.name;

     else

         parent = parent .. "nil";

     end

     local layer = "layer:" .. self.layer;

     local index = "index:" .. self.index;

     local name = "name:" .. self.name;

     print(root .. " " .. parent .. " " .. layer .. " " .. index .. " " .. name);

 end

BTParentTask.lua

 BTParentTask = BTTask:New();

 local this = BTParentTask;

 function this:New()

     local o = {};

     setmetatable(o, self);

     self.__index = self;

     o.currentChildIndex = ;  --当前运行到第几个子节点

     o.currentChildTask = nil; --当前运行的子节点

     o.childTasks = {};        --子节点列表

     return o;

 end

 --添加子节点

 function this:AddChild(task)

     local index = #self.childTasks + ;

     task.index = index;

     task.layer = self.layer + ;

     task.parent = self;

     task.root = self.root;

     self.childTasks[index] = task;

     if (BTBehaviorManager.isPrintTaskInfo) then

         print(task:ToString());

     end

 end

 --是否有子节点

 function this:HasChild()

     if (#self.childTasks > ) then

         return true;

     else

         return false;

     end

 end

 --获取子节点数目

 function this:GetChildCount()

     return #self.childTasks;

 end

 --获取下一个要执行的子节点

 function this:GetNextChild()

     if (#self.childTasks >= (self.currentChildIndex + )) then

         self.currentChildIndex = self.currentChildIndex + ;

         return self.childTasks[self.currentChildIndex];

     end

     return nil;

 end

 --重置

 function this:Reset()

     self.currentChildIndex = ;

     self.currentChildTask = nil;

 end

BTBehaviorTree.lua

 --[[

 树的根节点

 --]]

 BTBehaviorTree = BTTask:New();

 local this = BTBehaviorTree;

 function this:New()

     local o = {};

     setmetatable(o, self);

     self.__index = self;

     return o;

 end

 function this:SetStartTask(task)

     task.root = self;

     task.parent = self;

     task.layer = self.layer + ;

     self.startTask = task;

     if (BTBehaviorManager.isPrintTaskInfo) then

         print(task:ToString());

     end

 end

 function this:OnUpdate()

     if (self.startTask) then

         return self.startTask:OnUpdate();

     end

 end

TestBehaviorTree.lua

 TestBehaviorTree = BTBehaviorTree:New();

 local this = TestBehaviorTree;

 this.name = "TestBehaviorTree";

 function this:New()

     local o = {};

     setmetatable(o, self);

     self.__index = self;

     self:Init();

     return o;

 end

 function this:Init()

     local repeater = BTRepeater:New();

     local selector = BTSelector:New();

     local sequence = BTSequence:New();

     local isNullOrEmpty = BTIsNullOrEmpty:New("");

     local log = BTLog:New("This is a empty string!!!");

     local log2 = BTLog:New("This is not a empty string");

     self:SetStartTask(repeater);

     repeater:AddChild(selector);

     selector:AddChild(sequence);

     selector:AddChild(log2);

     sequence:AddChild(isNullOrEmpty);

     sequence:AddChild(log);

 end

打印如下：