Add **Behavior Tree** asset type and editing

Source/Engine/AI/BehaviorTree.cpp

@@ -0,0 +1,161 @@
+// Copyright (c) 2012-2023 Wojciech Figat. All rights reserved.
+
+#include "BehaviorTree.h"
+#include "BehaviorTreeNode.h"
+#include "BehaviorTreeNodes.h"
+#include "Engine/Content/Factories/BinaryAssetFactory.h"
+#include "Engine/Scripting/Scripting.h"
+#include "Engine/Serialization/JsonSerializer.h"
+#include "Engine/Serialization/MemoryReadStream.h"
+#include "Engine/Threading/Threading.h"
+#include "FlaxEngine.Gen.h"
+
+REGISTER_BINARY_ASSET(BehaviorTree, "FlaxEngine.BehaviorTree", false);
+
+BehaviorTreeGraphNode::~BehaviorTreeGraphNode()
+{
+    SAFE_DELETE(Instance);
+}
+
+bool BehaviorTreeGraph::Load(ReadStream* stream, bool loadMeta)
+{
+    if (VisjectGraph<BehaviorTreeGraphNode>::Load(stream, loadMeta))
+        return true;
+
+    // Build node instances hierarchy
+    for (Node& node : Nodes)
+    {
+        if (auto* nodeCompound = ScriptingObject::Cast<BehaviorTreeCompoundNode>(node.Instance))
+        {
+            for (const GraphBox* childBox : node.Boxes[1].Connections)
+            {
+                const Node* child = childBox ? (Node*)childBox->Parent : nullptr;
+                if (child && child->Instance)
+                {
+                    nodeCompound->Children.Add(child->Instance);
+                }
+            }
+        }
+    }
+
+    return false;
+}
+
+void BehaviorTreeGraph::Clear()
+{
+    VisjectGraph<BehaviorTreeGraphNode>::Clear();
+
+    Root = nullptr;
+}
+
+bool BehaviorTreeGraph::onNodeLoaded(Node* n)
+{
+    if (n->GroupID == 19 && (n->TypeID == 1 || n->TypeID == 2))
+    {
+        // Create node instance object
+        ScriptingTypeHandle type = Scripting::FindScriptingType((StringAnsiView)n->Values[0]);
+        if (!type)
+            type = Scripting::FindScriptingType(StringAnsi((StringView)n->Values[0]));
+        if (type)
+        {
+            n->Instance = (BehaviorTreeNode*)Scripting::NewObject(type);
+            const Variant& data = n->Values[1];
+            if (data.Type == VariantType::Blob)
+                JsonSerializer::LoadFromBytes(n->Instance, Span<byte>((byte*)data.AsBlob.Data, data.AsBlob.Length), FLAXENGINE_VERSION_BUILD);
+
+            // Find root node
+            if (!Root && n->Instance && BehaviorTreeRootNode::TypeInitializer == type)
+                Root = (BehaviorTreeRootNode*)n->Instance;
+        }
+        else
+        {
+            const String name = n->Values[0].ToString();
+            if (name.HasChars())
+                LOG(Error, "Missing type '{0}'", name);
+        }
+    }
+
+    return VisjectGraph<BehaviorTreeGraphNode>::onNodeLoaded(n);
+}
+
+BehaviorTree::BehaviorTree(const SpawnParams& params, const AssetInfo* info)
+    : BinaryAsset(params, info)
+{
+}
+
+BytesContainer BehaviorTree::LoadSurface()
+{
+    if (WaitForLoaded())
+        return BytesContainer();
+    ScopeLock lock(Locker);
+    if (!LoadChunks(GET_CHUNK_FLAG(0)))
+    {
+        const auto data = GetChunk(0);
+        BytesContainer result;
+        result.Copy(data->Data);
+        return result;
+    }
+    LOG(Warning, "\'{0}\' surface data is missing.", ToString());
+    return BytesContainer();
+}
+
+#if USE_EDITOR
+
+bool BehaviorTree::SaveSurface(const BytesContainer& data)
+{
+    // Wait for asset to be loaded or don't if last load failed
+    if (LastLoadFailed())
+    {
+        LOG(Warning, "Saving asset that failed to load.");
+    }
+    else if (WaitForLoaded())
+    {
+        LOG(Error, "Asset loading failed. Cannot save it.");
+        return true;
+    }
+
+    ScopeLock lock(Locker);
+
+    // Set Visject Surface data
+    GetOrCreateChunk(0)->Data.Copy(data);
+
+    // Save
+    AssetInitData assetData;
+    assetData.SerializedVersion = 1;
+    if (SaveAsset(assetData))
+    {
+        LOG(Error, "Cannot save \'{0}\'", ToString());
+        return true;
+    }
+
+    return false;
+}
+
+#endif
+
+Asset::LoadResult BehaviorTree::load()
+{
+    // Load graph
+    const auto surfaceChunk = GetChunk(0);
+    if (surfaceChunk == nullptr)
+        return LoadResult::MissingDataChunk;
+    MemoryReadStream surfaceStream(surfaceChunk->Get(), surfaceChunk->Size());
+    if (Graph.Load(&surfaceStream, true))
+    {
+        LOG(Warning, "Failed to load graph \'{0}\'", ToString());
+        return LoadResult::Failed;
+    }
+
+    return LoadResult::Ok;
+}
+
+void BehaviorTree::unload(bool isReloading)
+{
+    // Clear resources
+    Graph.Clear();
+}
+
+AssetChunksFlag BehaviorTree::getChunksToPreload() const
+{
+    return GET_CHUNK_FLAG(0);
+}