📌 Unity 최종 프로젝트

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📌 Behavior Tree Graph View Editor 제작

KiwiCoder의 BehaviorTree Editor를 참고하며 만들고 있는 중이다.

➔ Editor Image

Editor

UI Builder

Inspector

Create Menu

➔ Editor Code

BehaviorTree.cs

[CreateAssetMenu()]
public class BehaviorTree : ScriptableObject
{
    public Node rootNode;
    public Node.E_NodeState treeState = Node.E_NodeState.Running;
    public List<Node> nodes = new List<Node>();

    public Node.E_NodeState Update()
    {
        if (rootNode.state == Node.E_NodeState.Running)
        {
            treeState = rootNode.Update();
        }
        
        return treeState;
    }

    // 노드 객체 생성
    public Node CreateNode(System.Type type)
    {
        Node node = ScriptableObject.CreateInstance(type) as Node;
        
        if (node == null)
            Debug.LogError("node CreateInstance failed");

        node.name = type.Name;
        node.guid = GUID.Generate().ToString();
        nodes.Add(node);
        
        AssetDatabase.AddObjectToAsset(node, this);
        AssetDatabase.SaveAssets();

        return node;
    }

    // 노드 삭제
    public void DeleteNode(Node node)
    {
        nodes.Remove(node);
        AssetDatabase.RemoveObjectFromAsset(node);
        AssetDatabase.SaveAssets();
    }
}

BehaviorTreeEditor.cs

public class BehaviorTreeEditor : EditorWindow
{
    private BehaviorTreeView _treeView;
    private InspectorView _inspectorView;
    
    [MenuItem("BehaviorTree/BehaviorTree Editor")]
    public static void OpenWindow()
    {
        BehaviorTreeEditor wnd = GetWindow<BehaviorTreeEditor>();
        wnd.titleContent = new GUIContent("BehaviorTreeEditor");
    }

    public void CreateGUI()
    {
        // Each editor window contains a root VisualElement object
        VisualElement root = rootVisualElement;

        // Instantiate UXML
        var visualTree = AssetDatabase.LoadAssetAtPath<VisualTreeAsset>("Assets/__Scripts__/__Core__/Behavior Tree/Editor/BehaviorTreeEditor.uxml");
        visualTree.CloneTree(root);
        
        // Allocate StyleSheet 
        var styleSheet = AssetDatabase.LoadAssetAtPath<StyleSheet>("Assets/__Scripts__/__Core__/Behavior Tree/Editor/BehaviorTreeEditor.uss");
        root.styleSheets.Add(styleSheet);

        _treeView = root.Q<BehaviorTreeView>();
        _inspectorView = root.Q<InspectorView>();
        
        OnSelectionChange();
    }

    // 선택시 변경 이벤트 함수
    private void OnSelectionChange()
    {
        BehaviorTree tree = Selection.activeObject as BehaviorTree;

        if (tree)
        {
            _treeView.PopulateView(tree);
        }
    }
}

BehaviorTreeView.cs

public class BehaviorTreeView : GraphView
{
    private BehaviorTree _tree;
    
    public new class UxmlFactory : UxmlFactory<BehaviorTreeView, GraphView.UxmlTraits> { }
    public BehaviorTreeView()
    {
        Insert(0, new GridBackground()); // 백그라운드 드로우
        
        this.AddManipulator(new ContentZoomer());
        this.AddManipulator(new ContentDragger());
        this.AddManipulator(new SelectionDragger());
        this.AddManipulator(new RectangleSelector());
        
        var styleSheet = AssetDatabase.LoadAssetAtPath<StyleSheet>("Assets/__Scripts__/__Core__/Behavior Tree/Editor/BehaviorTreeEditor.uss");
        styleSheets.Add(styleSheet); // 스타일 시트 직접참조
    }

    internal void PopulateView(BehaviorTree tree)
    {
        _tree = tree;

        graphViewChanged -= OnGraphViewChanged;
        DeleteElements(graphElements);  // 두 개 이상 생성 대비 삭제
        graphViewChanged += OnGraphViewChanged;
        
        _tree.nodes.ForEach(n => CreateNodeView(n)); // 다시 생성
    }
    
    // 뷰 체인지 이벤트 함수
    private GraphViewChange OnGraphViewChanged(GraphViewChange graphViewChange)
    {
        if (graphViewChange.elementsToRemove != null)
        {
            graphViewChange.elementsToRemove.ForEach(element =>
            {
                if (element is NodeView nodeView)
                    _tree.DeleteNode(nodeView.node);
            });
        }

        return graphViewChange;
    }
    
    // 메뉴 재정의
    public override void BuildContextualMenu(ContextualMenuPopulateEvent evt)
    {
        {
            var types = TypeCache.GetTypesDerivedFrom<LeafAction>();
            foreach (var type in types)
            {
                evt.menu.AppendAction($"[{type.BaseType.Name}] {type.Name}", (t) => CreateNode(type));
            }
        }

        {
            var types = TypeCache.GetTypesDerivedFrom<Composite>();
            foreach (var type in types)
            {
                evt.menu.AppendAction($"[{type.BaseType.Name}] {type.Name}", (t) => CreateNode(type));
            }
        }

        {
            var types = TypeCache.GetTypesDerivedFrom<Decorator>();
            foreach (var type in types)
            {
                evt.menu.AppendAction($"[{type.BaseType.Name}] {type.Name}", (t) => CreateNode(type));
            }
        }
    }

    private void CreateNode(System.Type type)
    {
        Node node = _tree.CreateNode(type);
        CreateNodeView(node);
    }

    private void CreateNodeView(Node node)
    {
        NodeView nodeView = new NodeView(node);
        AddElement(nodeView);
    }
}

InspectorView.cs

public class InspectorView : VisualElement
{
    public new class UxmlFactory : UxmlFactory<InspectorView, VisualElement.UxmlTraits> {}
    
    public InspectorView()
    {
        
    }
}

NodeView.cs

public class NodeView : UnityEditor.Experimental.GraphView.Node
{
    public Node node;

    public NodeView(Node node)
    {
        this.node = node;
        this.title = node.name;
        this.viewDataKey = node.guid;

        style.left = node.position.x;
        style.top = node.position.y;
    }

    public override void SetPosition(Rect newPos)
    {
        base.SetPosition(newPos);
        
        node.position.x = newPos.xMin;
        node.position.y = newPos.yMin;
    }
    
    
}

SplitView.cs

public class SplitView : TwoPaneSplitView
{
    public new class UxmlFactory : UxmlFactory<SplitView, TwoPaneSplitView.UxmlTraits> { }
}

BehaviorTreeEditor.uss

GridBackground 
{
    --gird-background-color: rgb(40, 40, 40);
    --line-color: rgba(193, 196, 192, 0.1);
    --thick-line-color: rgba(193, 196, 192, 0.1);
    --spacing: 15;
}

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📌 출저

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