Why another Behavior Tree framework?

Features

Disadvantages

Packages

HowTo

Installation

{  "dependencies": {    ...    "com.quabug.entities-bt.builder.graphview": "1.4.0",  },  "scopedRegistries": [    {      "name": "package.openupm.com",      "url": "https://package.openupm.com",      "scopes": [        "com.quabug"      ]    }  ]}

openupm add com.quabug.entities-bt.builder.graphview

Usage

GraphView Builder

Create behavior tree graph

Attach graph of behavior tree ontoEntity

Component Builder

Create behavior tree

Attach behavior tree ontoEntity

Serialization

Thread control

Variant

Variant Types

Variant Sources

Code Example

[BehaviorNode("867BFC14-4293-4D4E-B3F0-280AD4BAA403")]publicstructVariantNode:INodeData{publicBlobVariantReader<int>IntVariant;publicBlobVariantReaderAndWriter<float>FloatVariant;publicNodeStateTick<TNodeBlob,TBlackboard>(intindex,refTNodeBlobblob,refTBlackboardblackboard)whereTNodeBlob:struct,INodeBlobwhereTBlackboard:struct,IBlackboard{varintVariant=IntVariant.Read(index,refblob,refblackboard);// get variable valuevarfloatVariant=FloatVariant.Read(index,refblob,refblackboard);FloatVariant.Write(index,refblob,refblackboard,floatVariant+1);returnNodeState.Success;}publicvoidReset<TNodeBlob,TBlackboard>(intindex,refTNodeBlobblob,refTBlackboardbb)whereTNodeBlob:struct,INodeBlobwhereTBlackboard:struct,IBlackboard{}}

Multiple Trees

Debug

Custom behavior node

Action

// most important part of node, actual logic on runtime.[Serializable]// for debug view only[BehaviorNode("F5C2EE7E-690A-4B5C-9489-FB362C949192")]// must add this attribute to indicate a class is a `BehaviorNode`publicstructEntityMoveNode:INodeData{publicfloat3Velocity;// node data saved in `INodeBlob`publicNodeStateTick<TNodeBlob,TBlackboard>(intindex,refTNodeBlobblob,refTBlackboardbb)whereTNodeBlob:struct,INodeBlobwhereTBlackboard:struct,IBlackboard{// access and modify node datarefvartranslation=refbb.GetDataRef<Translation>();// get blackboard data by ref (read/write)vardeltaTime=bb.GetData<BehaviorTreeTickDeltaTime>();// get blackboard data by value (readonly)translation.Value+=Velocity*deltaTime.Value;returnNodeState.Running;}publicvoidReset<TNodeBlob,TBlackboard>(intindex,refTNodeBlobblob,refTBlackboardbb)whereTNodeBlob:struct,INodeBlobwhereTBlackboard:struct,IBlackboard{}}// debug view (optional)publicclassEntityMoveDebugView:BTDebugView<EntityMoveNode>{}

Decorator

// runtime behavior[Serializable]// for debug view only[BehaviorNode("A13666BD-48E3-414A-BD13-5C696F2EA87E",BehaviorNodeType.Decorate/*decorator must explicit declared*/)]publicstructRepeatForeverNode:INodeData{publicNodeStateBreakStates;publicNodeStateTick<TNodeBlob,TBlackboard>(intindex,refTNodeBlobblob,refTBlackboardblackboard)whereTNodeBlob:struct,INodeBlobwhereTBlackboard:struct,IBlackboard{// short-cut to tick first only childrenvarchildState=blob.TickChildrenReturnFirstOrDefault(index,blackboard);if(childState==0)// 0 means no child was ticked// tick an already completed `Sequence` or `Selector` will return 0{blob.ResetChildren(index,blackboard);childState=blob.TickChildrenReturnFirstOrDefault(index,blackboard);}if(BreakStates.HasFlag(childState))returnchildState;returnNodeState.Running;}publicvoidReset<TNodeBlob,TBlackboard>(intindex,refTNodeBlobblob,refTBlackboardbb)whereTNodeBlob:struct,INodeBlobwhereTBlackboard:struct,IBlackboard{}}// debug view (optional)publicclassBTDebugRepeatForever:BTDebugView<RepeatForeverNode>{}

Composite

// runtime behavior[StructLayout(LayoutKind.Explicit)]// sizeof(SelectorNode) == 0[BehaviorNode("BD4C1D8F-BA8E-4D74-9039-7D1E6010B058",BehaviorNodeType.Composite/*composite must explicit declared*/)]publicstructSelectorNode:INodeData{publicNodeStateTick<TNodeBlob,TBlackboard>(intindex,refTNodeBlobblob,refTBlackboardblackboard)whereTNodeBlob:struct,INodeBlobwhereTBlackboard:struct,IBlackboard{// tick children and break if the child state is running or success.returnblob.TickChildrenReturnLastOrDefault(index,blackboard,breakCheck: state=>state.IsRunningOrSuccess());}publicvoidReset<TNodeBlob,TBlackboard>(intindex,refTNodeBlobblob,refTBlackboardbb)whereTNodeBlob:struct,INodeBlobwhereTBlackboard:struct,IBlackboard{}}// avoid debugging view since there's nothing that needs to debug for `Selector`

EntityQuery

publicstructSomeNode:INodeData{// read-only accessBlobVariantReader<int>IntVariable;// read-write access (there's no write-only access)BlobVariantWriter<float>FloatVariable;// read-write accessBlobVariantReaderAndWriter<double>FloatVariable;// leave method attribute to be empty and will generate right access of this methodpublicNodeStateTick<TNodeBlob,TBlackboard>(intindex,refTNodeBlobblob,refTBlackboardblackboard)whereTNodeBlob:struct,INodeBlobwhereTBlackboard:struct,IBlackboard{// generate `[ReadOnly(typeof(ReadOnlyComponent)]` on `Tick` methodbb.GetData<ReadOnlyComponent>();// generate `[ReadWrite(typeof(ReadWriteComponent)]` on `Tick` methodbb.GetDataRef<ReadWriteComponent>();returnNodeState.Success;}// or manually declare right access types for this method[EntitiesBT.Core.ReadWrite(typeof(ReadWriteComponentData))][EntitiesBT.Core.ReadOnly(typeof(ReadOnlyComponentData))]publicvoidReset<TNodeBlob,TBlackboard>(intindex,refTNodeBlobblob,refTBlackboardbb)whereTNodeBlob:struct,INodeBlobwhereTBlackboard:struct,IBlackboard{// generate `[ReadOnly(typeof(ReadOnlyComponent)]` on `Reset` methodbb.GetData<ReadOnlyComponent>();// generate `[ReadWrite(typeof(ReadWriteComponent)]` on `Reset` methodbb.GetDataRef<ReadWriteComponent>();// ...}}

publicstaticclassExtension{[ReadOnly(typeof(FooComponent)),ReadWrite(typeof(BarComponent))]publicstaticvoidCall<[ReadWrite]T,[ReadOnly]U>([ReadOnly]Typetype){/* ... */}}publicstructSomeNode:INodeData{// leave method attribute to be empty to generate automaticallypublicNodeStateTick<TNodeBlob,TBlackboard>(intindex,refTNodeBlobblob,refTBlackboardblackboard)whereTNodeBlob:struct,INodeBlobwhereTBlackboard:struct,IBlackboard{// the following call will generate access attributes on `Tick` as below:// [ReadOnly(typeof(FooComponent))]// [ReadWrite(typeof(BarComponent))]// [ReadWrite(typeof(int))]// [ReadOnly(typeof(float))]// [ReadOnly(typeof(long))]Extension.Call<int,float>(typeof(long));returnNodeState.Success;}}

Advanced: customize debug view

Advanced: access other node data

Advanced: behavior tree component

[BehaviorTreeComponent]// mark a component data as `BehaviorTreeComponent`publicstructBehaviorTreeTickDeltaTime:IComponentData{publicfloatValue;}[UpdateBefore(typeof(VirtualMachineSystem))]publicclassBehaviorTreeDeltaTimeSystem:ComponentSystem{protectedoverridevoidOnUpdate(){Entities.ForEach((refBehaviorTreeTickDeltaTimedeltaTime)=>deltaTime.Value=Time.DeltaTime);}}

Advanced: virtual node builder

publicclassBTSequence:BTNode<SequenceNode>{[Tooltip("Enable this will re-evaluate node state from the first child until running node instead of skip to the running node directly.")][SerializeField]privatebool_recursiveResetStatesBeforeTick;publicoverrideINodeDataBuilderSelf=>_recursiveResetStatesBeforeTick// add `RecursiveResetStateNode` as the parent of `this` node?newBTVirtualDecorator<RecursiveResetStateNode>(this):base.Self;}

Data Structure

publicstructNodeBlob{// default data (serializable data)publicBlobArray<int>Types;// type id of behavior node, generated from `Guid` of `BehaviorNodeAttribute`publicBlobArray<int>EndIndices;// range of node branch must be in [nodeIndex, nodeEndIndex)publicBlobArray<int>Offsets;// data offset of `DefaultDataBlob` of this nodepublicBlobArray<byte>DefaultDataBlob;// nodes data// runtime only data (only exist on runtime)publicBlobArray<NodeState>States;// nodes states// initialize from `DefaultDataBlob`publicBlobArray<byte>RuntimeDataBlob;// same as `DefaultNodeData` but only available at runtime and will reset to `DefaultNodeData` once reset.}