Minor refactor.

This is a prerequisite to properly track Node input/output connections and to compute eval order in the BlendTreeResources.

CMakeLists.txt

@@ -39,21 +39,25 @@ set(ThirdPartyIncludeDeps
         PUBLIC $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/3rdparty/sokol>
         PUBLIC $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/3rdparty/vectorial/include>
         PUBLIC $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/>
-        )
+)
 
 # Shared code by main executable and tests
 add_library(AnimTestbedCode OBJECT
         src/SyncTrack.cc
         src/SyncTrack.h
         src/ozzutils.cc
-        src/AnimGraph/AnimGraphResource.cc
-        src/AnimGraph/AnimGraphResource.h
-        src/AnimGraph/AnimGraph.cc
-        src/AnimGraph/AnimGraph.h
         src/AnimGraph/AnimGraphNodes.cc
         src/AnimGraph/AnimGraphNodes.h
         src/AnimGraph/AnimGraphData.cc
-        src/AnimGraph/AnimGraphData.h)
+        src/AnimGraph/AnimGraphData.h
+        src/AnimGraph/AnimGraphBlendTree.cc
+        src/AnimGraph/AnimGraphBlendTree.h
+        src/AnimGraph/AnimGraphStateMachine.cc
+        src/AnimGraph/AnimGraphStateMachine.h
+        src/AnimGraph/AnimNode.cc
+        src/AnimGraph/AnimNode.h
+        src/AnimGraph/AnimGraphResource.cc
+        src/AnimGraph/AnimGraphResource.h)
 
 target_include_directories(
         AnimTestbedCode
@@ -74,6 +78,7 @@ target_include_directories(
 
 target_sources(AnimTestbed PRIVATE
         src/main.cc
+        src/embedded_fonts.h
         src/SkinnedMeshRenderer.cc
         src/AnimGraph/AnimGraphEditor.cc
         src/AnimGraph/AnimGraphEditor.h
@@ -104,7 +109,7 @@ target_sources(AnimTestbed PRIVATE
         3rdparty/imgui-node-editor/imgui_extra_math.inl
         3rdparty/imgui-node-editor/crude_json.cpp
         3rdparty/imgui-node-editor/crude_json.h
-        )
+)
 
 target_link_libraries(AnimTestbed AnimTestbedCode glfw ozz_base ozz_geometry ozz_animation ${OPENGL_LIBRARIES})
 
@@ -116,16 +121,17 @@ set(ozz_offline_test_objs
         3rdparty/ozz-animation/src/animation/offline/raw_skeleton.cc
         3rdparty/ozz-animation/src/animation/offline/animation_builder.cc
         3rdparty/ozz-animation/src/animation/offline/raw_animation.cc
-        )
+)
 
 target_sources(runtests PRIVATE
         tests/AnimGraphResourceTests.cc
-        tests/AnimGraphEvalTests.cc
+        tests/AnimGraphEditorTests.cc
+        # tests/AnimGraphEvalTests.cc
         tests/NodeDescriptorTests.cc
         tests/SyncTrackTests.cc
         tests/main.cc
         ${ozz_offline_test_objs}
-        )
+)
 
 target_include_directories(
         runtests

src/AnimGraph/AnimGraph.cc

@@ -1,202 +0,0 @@
-//
-// Created by martin on 25.03.22.
-//
-
-#include "AnimGraph.h"
-
-#include <algorithm>
-#include <cstring>
-
-bool AnimGraph::init(AnimGraphContext& context) {
-  context.m_graph = this;
-
-  for (size_t i = 2; i < m_nodes.size(); i++) {
-    if (!m_nodes[i]->Init(context)) {
-      return false;
-    }
-  }
-
-  for (size_t i = 0; i < m_animdata_blocks.size(); i++) {
-    int num_soa_joints = context.m_skeleton->num_soa_joints();
-    m_animdata_blocks[i]->m_local_matrices.resize(num_soa_joints);
-  }
-
-  return true;
-}
-
-void AnimGraph::updateOrderedNodes() {
-  m_eval_ordered_nodes.clear();
-  updateOrderedNodesRecursive(0);
-}
-
-void AnimGraph::updateOrderedNodesRecursive(int node_index) {
-  AnimNode* node = m_nodes[node_index];
-  const std::vector<AnimGraphConnection>& node_input_connections =
-      m_node_input_connections[node_index];
-  for (size_t i = 0, n = node_input_connections.size(); i < n; i++) {
-    int input_node_index =
-        getAnimNodeIndex(node_input_connections.at(i).m_source_node);
-
-    if (input_node_index == 1) {
-      continue;
-    }
-
-    updateOrderedNodesRecursive(input_node_index);
-  }
-
-  if (node_index != 0) {
-    // In case we have multiple output connections from the node we here
-    // ensure that use the node evaluation that is the furthest away from
-    // the output.
-    std::vector<AnimNode*>::iterator find_iter = std::find(
-        m_eval_ordered_nodes.begin(),
-        m_eval_ordered_nodes.end(),
-        node);
-    if (find_iter != m_eval_ordered_nodes.end()) {
-      m_eval_ordered_nodes.erase(find_iter);
-    }
-
-    m_eval_ordered_nodes.push_back(node);
-  }
-}
-
-void AnimGraph::markActiveNodes() {
-  for (size_t i = 0, n = m_nodes.size(); i < n; i++) {
-    m_nodes[i]->m_state = AnimNodeEvalState::Deactivated;
-  }
-
-  const std::vector<AnimGraphConnection>& graph_output_inputs =
-      m_node_input_connections[0];
-  for (size_t i = 0, n = graph_output_inputs.size(); i < n; i++) {
-    const AnimGraphConnection& graph_input = graph_output_inputs[i];
-    AnimNode* node = graph_input.m_source_node;
-    if (node != nullptr) {
-      node->m_state = AnimNodeEvalState::Activated;
-    }
-  }
-
-  for (size_t i = m_eval_ordered_nodes.size() - 1; i > 0; i--) {
-    AnimNode* node = m_eval_ordered_nodes[i];
-    if (checkIsNodeActive(node)) {
-      int node_index = node->m_index;
-      node->MarkActiveInputs(m_node_input_connections[node_index]);
-
-      // Non-animation data inputs are always active.
-      for (size_t j = 0, nj = m_node_input_connections[node_index].size();
-           j < nj;
-           j++) {
-        const AnimGraphConnection& input =
-            m_node_input_connections[node_index][j];
-        if (input.m_source_node != nullptr
-            && input.m_target_socket.m_type
-                   != SocketType::SocketTypeAnimation) {
-          input.m_source_node->m_state = AnimNodeEvalState::Activated;
-        }
-      }
-    }
-  }
-}
-
-void AnimGraph::evalSyncTracks() {
-  for (size_t i = m_eval_ordered_nodes.size() - 1; i >= 0; i--) {
-    AnimNode* node = m_eval_ordered_nodes[i];
-    int node_index = node->m_index;
-    if (node->m_state == AnimNodeEvalState::Deactivated) {
-      continue;
-    }
-
-    node->CalcSyncTrack(m_node_input_connections[node_index]);
-  }
-}
-
-void AnimGraph::updateTime(float dt) {
-  const std::vector<AnimGraphConnection>& graph_output_inputs =
-      m_node_input_connections[0];
-  for (size_t i = 0, n = graph_output_inputs.size(); i < n; i++) {
-    AnimNode* node = graph_output_inputs[i].m_source_node;
-    if (node != nullptr) {
-      node->UpdateTime(node->m_time_now, node->m_time_now + dt);
-    }
-  }
-
-  for (size_t i = m_eval_ordered_nodes.size() - 1; i > 0; --i) {
-    AnimNode* node = m_eval_ordered_nodes[i];
-    if (node->m_state != AnimNodeEvalState::TimeUpdated) {
-      continue;
-    }
-
-    int node_index = node->m_index;
-    float node_time_now = node->m_time_now;
-    float node_time_last = node->m_time_last;
-
-    const std::vector<AnimGraphConnection>& node_input_connections =
-        m_node_input_connections[node_index];
-    for (size_t i = 0, n = node_input_connections.size(); i < n; i++) {
-      AnimNode* input_node = node_input_connections[i].m_source_node;
-
-      // Only propagate time updates via animation sockets.
-      if (input_node != nullptr
-          && node_input_connections[i].m_target_socket.m_type
-                 == SocketType::SocketTypeAnimation
-          && input_node->m_state == AnimNodeEvalState::Activated) {
-        input_node->UpdateTime(node_time_last, node_time_now);
-      }
-    }
-  }
-}
-
-void AnimGraph::evaluate(AnimGraphContext& context) {
-  for (int i = 0, n = m_eval_ordered_nodes.size(); i < n; i++) {
-    AnimNode* node = m_eval_ordered_nodes[i];
-
-    if (node->m_state == AnimNodeEvalState::Deactivated) {
-      continue;
-    }
-
-    node->Evaluate(context);
-  }
-}
-
-Socket* AnimGraph::getInputSocket(const std::string& name) {
-  for (size_t i = 0, n = m_node_output_connections[1].size(); i < n; i++) {
-    AnimGraphConnection& connection = m_node_output_connections[1][i];
-    if (connection.m_source_socket.m_name == name) {
-      return &connection.m_source_socket;
-    }
-  }
-
-  return nullptr;
-}
-
-Socket* AnimGraph::getOutputSocket(const std::string& name) {
-  for (size_t i = 0, n = m_node_input_connections[0].size(); i < n; i++) {
-    AnimGraphConnection& connection = m_node_input_connections[0][i];
-    if (connection.m_target_socket.m_name == name) {
-      return &connection.m_target_socket;
-    }
-  }
-
-  return nullptr;
-}
-
-const Socket* AnimGraph::getInputSocket(const std::string& name) const {
-  for (size_t i = 0, n = m_node_output_connections[1].size(); i < n; i++) {
-    const AnimGraphConnection& connection = m_node_output_connections[1][i];
-    if (connection.m_source_socket.m_name == name) {
-      return &connection.m_source_socket;
-    }
-  }
-
-  return nullptr;
-}
-
-const Socket* AnimGraph::getOutputSocket(const std::string& name) const {
-  for (size_t i = 0, n = m_node_input_connections[0].size(); i < n; i++) {
-    const AnimGraphConnection& connection = m_node_input_connections[0][i];
-    if (connection.m_target_socket.m_name == name) {
-      return &connection.m_target_socket;
-    }
-  }
-
-  return nullptr;
-}

src/AnimGraph/AnimGraph.h

@@ -1,231 +0,0 @@
-//
-// Created by martin on 25.03.22.
-//
-
-#ifndef ANIMTESTBED_ANIMGRAPH_H
-#define ANIMTESTBED_ANIMGRAPH_H
-
-#include "AnimGraphData.h"
-#include "AnimGraphNodes.h"
-
-//
-// AnimGraph (Runtime)
-//
-struct AnimGraph {
-  AnimData m_local_transforms;
-
-  std::vector<AnimNode*> m_nodes;
-  std::vector<AnimNode*> m_eval_ordered_nodes;
-  std::vector<std::vector<AnimGraphConnection> > m_node_input_connections;
-  std::vector<std::vector<AnimGraphConnection> > m_node_output_connections;
-  std::vector<AnimData*> m_animdata_blocks;
-  NodeDescriptorBase* m_node_descriptor = nullptr;
-  char* m_input_buffer = nullptr;
-  char* m_output_buffer = nullptr;
-  char* m_connection_data_storage = nullptr;
-  char* m_const_node_inputs = nullptr;
-
-  std::vector<Socket>& getGraphOutputs() { return m_node_descriptor->m_inputs; }
-  std::vector<Socket>& getGraphInputs() { return m_node_descriptor->m_outputs; }
-
-  AnimDataAllocator m_anim_data_allocator;
-
-  ~AnimGraph() { dealloc(); }
-
-  bool init(AnimGraphContext& context);
-  void dealloc() {
-    for (size_t i = 0; i < m_animdata_blocks.size(); i++) {
-      m_animdata_blocks[i]->m_local_matrices.vector::~vector();
-    }
-    m_animdata_blocks.clear();
-
-    m_node_input_connections.clear();
-    m_node_output_connections.clear();
-
-    delete[] m_input_buffer;
-    delete[] m_output_buffer;
-    delete[] m_connection_data_storage;
-    delete[] m_const_node_inputs;
-
-    for (int i = 0; i < m_nodes.size(); i++) {
-      delete m_nodes[i];
-    }
-    m_nodes.clear();
-
-    delete m_node_descriptor;
-  }
-
-  void updateOrderedNodes();
-  void updateOrderedNodesRecursive(int node_index);
-  void markActiveNodes();
-  bool checkIsNodeActive(AnimNode* node) {
-    return node->m_state != AnimNodeEvalState::Deactivated;
-  }
-
-  void evalSyncTracks();
-  void updateTime(float dt);
-  void evaluate(AnimGraphContext& context);
-  void resetNodeStates() {
-    for (size_t i = 0, n = m_nodes.size(); i < n; i++) {
-      m_nodes[i]->m_time_now = 0.f;
-      m_nodes[i]->m_time_last = 0.f;
-      m_nodes[i]->m_state = AnimNodeEvalState::Undefined;
-    }
-  }
-
-  Socket* getInputSocket(const std::string& name);
-  Socket* getOutputSocket(const std::string& name);
-
-  const Socket* getInputSocket(const std::string& name) const;
-  const Socket* getOutputSocket(const std::string& name) const;
-
-  /** Sets the address that is used for the specified AnimGraph input Socket.
-   *
-   * @tparam T Type of the Socket.
-   * @param name Name of the Socket.
-   * @param value_ptr Pointer where the input is fetched during evaluation.
-   */
-  template <typename T>
-  void SetInput(const char* name, T* value_ptr) {
-    m_node_descriptor->SetOutput(name, value_ptr);
-
-    for (int i = 0; i < m_node_output_connections[1].size(); i++) {
-      const AnimGraphConnection& graph_input_connection =
-          m_node_output_connections[1][i];
-
-      if (graph_input_connection.m_source_socket.m_name == name) {
-        *graph_input_connection.m_target_socket.m_reference.ptr_ptr = value_ptr;
-      }
-    }
-  }
-
-  /** Sets the address that is used for the specified AnimGraph output Socket.
-   *
-   * @tparam T Type of the Socket.
-   * @param name Name of the Socket.
-   * @param value_ptr Pointer where the graph output output is written to at the end of evaluation.
-   */
-  template <typename T>
-  void SetOutput(const char* name, T* value_ptr) {
-    m_node_descriptor->SetInput(name, value_ptr);
-
-    for (int i = 0; i < m_node_input_connections[0].size(); i++) {
-      const AnimGraphConnection& graph_output_connection =
-          m_node_input_connections[0][i];
-
-      if (graph_output_connection.m_target_socket.m_name == name) {
-        if (graph_output_connection.m_source_node == m_nodes[1]
-            && graph_output_connection.m_target_node == m_nodes[0]) {
-          std::cerr << "Error: cannot set output for direct graph input to graph "
-                       "output connections. Use GetOutptPtr for output instead!"
-                    << std::endl;
-
-          return;
-        }
-
-        *graph_output_connection.m_source_socket.m_reference.ptr_ptr =
-            value_ptr;
-
-        // Make sure all other output connections of this pin use the same output pointer
-        int source_node_index = getAnimNodeIndex(graph_output_connection.m_source_node);
-        for (int j = 0; j < m_node_output_connections[source_node_index].size(); j++) {
-          const AnimGraphConnection& source_output_connection = m_node_output_connections[source_node_index][j];
-          if (source_output_connection.m_target_node == m_nodes[0]) {
-            continue;
-          }
-
-          if (source_output_connection.m_source_socket.m_name == graph_output_connection.m_source_socket.m_name) {
-            *source_output_connection.m_target_socket.m_reference.ptr_ptr = value_ptr;
-          }
-        }
-      }
-    }
-  }
-
-  /** Returns the address that is used for the specified AnimGraph output Socket.
-   *
-   * This function is needed for connections that directly connect an AnimGraph
-   * input Socket to an output Socket of the same AnimGraph.
-   *
-   * @tparam T Type of the Socket.
-   * @param name Name of the Socket.
-   * @return Address that is used for the specified AnimGraph output Socket.
-   */
-  template <typename T>
-  T* GetOutputPtr(const char* name) {
-    for (int i = 0; i < m_node_input_connections[0].size(); i++) {
-      const AnimGraphConnection& graph_output_connection =
-          m_node_input_connections[0][i];
-      if (graph_output_connection.m_target_socket.m_name == name) {
-        return static_cast<float*>(*graph_output_connection.m_source_socket.m_reference.ptr_ptr);
-      }
-    }
-
-    return nullptr;
-  }
-
-  void* getInputPtr(const std::string& name) const {
-    const Socket* input_socket = getInputSocket(name);
-    if (input_socket != nullptr) {
-      return input_socket->m_reference.ptr;
-    }
-
-    return nullptr;
-  }
-
-  void* getOutputPtr(const std::string& name) const {
-    const Socket* input_socket = getOutputSocket(name);
-    if (input_socket != nullptr) {
-      return input_socket->m_reference.ptr;
-    }
-
-    return nullptr;
-  }
-
-  int getNodeEvalOrderIndex(const AnimNode* node) {
-    for (size_t i = 0, n = m_eval_ordered_nodes.size(); i < n; i++) {
-      if (m_eval_ordered_nodes[i] == node) {
-        return i;
-      }
-    }
-
-    return -1;
-  }
-  const AnimNode* getAnimNodeForInput(
-      size_t node_index,
-      const std::string& input_name) const {
-    assert(node_index < m_nodes.size());
-
-    const std::vector<AnimGraphConnection>& input_connection =
-        m_node_input_connections[node_index];
-    for (size_t i = 0, n = input_connection.size(); i < n; i++) {
-      if (input_connection[i].m_target_socket.m_name == input_name) {
-        return input_connection[i].m_source_node;
-      }
-    }
-
-    return nullptr;
-  }
-
-  AnimNode* getAnimNode(const char* name) {
-    for (size_t i = 0; i < m_nodes.size(); i++) {
-      if (m_nodes[i]->m_name == name) {
-        return m_nodes[i];
-      }
-    }
-
-    return nullptr;
-  }
-
-  size_t getAnimNodeIndex(AnimNode* node) {
-    for (size_t i = 0; i < m_nodes.size(); i++) {
-      if (m_nodes[i] == node) {
-        return i;
-      }
-    }
-
-    return -1;
-  }
-};
-
-#endif  //ANIMTESTBED_ANIMGRAPH_H

src/AnimGraph/AnimGraphBlendTree.cc

@@ -0,0 +1,176 @@
+#pragma clang diagnostic push
+#pragma ide diagnostic ignored "misc-no-recursion"
+//
+// Created by martin on 17.03.24.
+//
+
+#include "AnimGraphBlendTree.h"
+
+#include <algorithm>
+
+bool AnimGraphBlendTree::Init(AnimGraphContext& context) {
+  for (size_t i = 2; i < m_nodes.size(); i++) {
+    if (!m_nodes[i]->Init(context)) {
+      return false;
+    }
+  }
+
+  for (size_t i = 0; i < m_animdata_blocks.size(); i++) {
+    int num_soa_joints = context.m_skeleton->num_soa_joints();
+    m_animdata_blocks[i]->m_local_matrices.resize(num_soa_joints);
+  }
+
+  return true;
+}
+
+void AnimGraphBlendTree::UpdateOrderedNodes() {
+  m_eval_ordered_nodes.clear();
+  UpdateOrderedNodesRecursive(0);
+}
+
+void AnimGraphBlendTree::UpdateOrderedNodesRecursive(int node_index) {
+  AnimNode* node = m_nodes[node_index];
+  const std::vector<AnimGraphConnection>& node_input_connections =
+      m_node_input_connections[node_index];
+  for (size_t i = 0, n = node_input_connections.size(); i < n; i++) {
+    if (node_input_connections[i].m_crosses_hierarchy) {
+      continue;
+    }
+
+    int input_node_index =
+        GetAnimNodeIndex(node_input_connections[i].m_source_node);
+
+    if (input_node_index == 1) {
+      continue;
+    }
+
+    UpdateOrderedNodesRecursive(input_node_index);
+  }
+
+  if (node_index != 0) {
+    // In case we have multiple output connections from the node we here
+    // ensure that use the node evaluation that is the furthest away from
+    // the output.
+    std::vector<AnimNode*>::iterator find_iter = std::find(
+        m_eval_ordered_nodes.begin(),
+        m_eval_ordered_nodes.end(),
+        node);
+    if (find_iter != m_eval_ordered_nodes.end()) {
+      m_eval_ordered_nodes.erase(find_iter);
+    }
+
+    m_eval_ordered_nodes.push_back(node);
+  }
+}
+
+void AnimGraphBlendTree::MarkActiveInputs(
+    const std::vector<AnimGraphConnection>& input_connections) {
+  for (AnimNode* node : m_nodes) {
+    if (node->m_tick_number != m_tick_number) {
+      node->m_state = AnimNodeEvalState::Deactivated;
+    }
+  }
+
+  const std::vector<AnimGraphConnection>& graph_output_inputs =
+      m_node_input_connections[0];
+  for (size_t i = 0, n = graph_output_inputs.size(); i < n; i++) {
+    const AnimGraphConnection& graph_input = graph_output_inputs[i];
+    AnimNode* node = graph_input.m_source_node;
+    if (node != nullptr) {
+      node->m_tick_number = m_tick_number;
+      node->m_state = AnimNodeEvalState::Activated;
+    }
+  }
+
+  for (int i = m_eval_ordered_nodes.size() - 1; i >= 0; i--) {
+    AnimNode* node = m_eval_ordered_nodes[i];
+    if (CheckIsNodeActive(node)) {
+      size_t node_index = GetAnimNodeIndex(node);
+      node->MarkActiveInputs(m_node_input_connections[node_index]);
+
+      // Non-animation data inputs are always active.
+      for (size_t j = 0, nj = m_node_input_connections[node_index].size();
+           j < nj;
+           j++) {
+        const AnimGraphConnection& input =
+            m_node_input_connections[node_index][j];
+        if (input.m_source_node != nullptr
+            && input.m_socket.m_type != SocketType::SocketTypeAnimation) {
+          input.m_source_node->m_state = AnimNodeEvalState::Activated;
+        }
+      }
+    }
+  }
+}
+
+void AnimGraphBlendTree::CalcSyncTrack(
+    const std::vector<AnimGraphConnection>& input_connections) {
+  for (int i = m_eval_ordered_nodes.size() - 1; i >= 0; i--) {
+    AnimNode* node = m_eval_ordered_nodes[i];
+    if (node->m_state == AnimNodeEvalState::Deactivated) {
+      continue;
+    }
+
+    node->CalcSyncTrack(m_node_input_connections[GetAnimNodeIndex(node)]);
+  }
+}
+
+void AnimGraphBlendTree::UpdateTime(float time_last, float time_now) {
+  float dt = time_now - time_last;
+
+  const std::vector<AnimGraphConnection>& graph_output_inputs =
+      m_node_input_connections[0];
+  for (const AnimGraphConnection& graph_output_input : graph_output_inputs) {
+    AnimNode* node = graph_output_input.m_source_node;
+    if (node != nullptr && node->m_state != AnimNodeEvalState::TimeUpdated) {
+      node->UpdateTime(time_last, time_now);
+    }
+  }
+
+  for (int i = m_eval_ordered_nodes.size() - 1; i >= 0; --i) {
+    AnimNode* node = m_eval_ordered_nodes[i];
+    if (node->m_state != AnimNodeEvalState::TimeUpdated) {
+      continue;
+    }
+
+    PropagateTimeToNodeInputs(node);
+  }
+
+  m_state = AnimNodeEvalState::TimeUpdated;
+}
+
+void AnimGraphBlendTree::Evaluate(AnimGraphContext& context) {
+  for (int i = 0, n = m_eval_ordered_nodes.size(); i < n; i++) {
+    AnimNode* node = m_eval_ordered_nodes[i];
+
+    if (node->m_state == AnimNodeEvalState::Deactivated) {
+      continue;
+    }
+
+    node->Evaluate(context);
+  }
+}
+
+void AnimGraphBlendTree::PropagateTimeToNodeInputs(const AnimNode* node) {
+  size_t node_index = GetAnimNodeIndex(node);
+
+  float node_time_now = node->m_time_now;
+  float node_time_last = node->m_time_last;
+
+  const std::vector<AnimGraphConnection>& node_input_connections =
+      m_node_input_connections[node_index];
+  for (const AnimGraphConnection& node_input_connection :
+       node_input_connections) {
+    AnimNode* input_node = node_input_connection.m_source_node;
+
+    // Only propagate time updates via animation sockets.
+    if (input_node != nullptr
+        && node_input_connection.m_socket.m_type
+               == SocketType::SocketTypeAnimation
+        && input_node->m_state == AnimNodeEvalState::Activated) {
+      input_node->UpdateTime(node_time_last, node_time_now);
+    }
+  }
+}
+
+#pragma clang diagnostic pop

src/AnimGraph/AnimGraphBlendTree.h

@@ -0,0 +1,213 @@
+//
+// Created by martin on 17.03.24.
+//
+
+#ifndef ANIMTESTBED_ANIMGRAPHBLENDTREE_H
+#define ANIMTESTBED_ANIMGRAPHBLENDTREE_H
+
+#include <algorithm>
+
+#include "AnimNode.h"
+
+//
+// AnimGraph (Runtime)
+//
+struct AnimGraphBlendTree : public AnimNode {
+  AnimData m_local_transforms;
+
+  std::vector<AnimNode*> m_nodes;
+  std::vector<AnimNode*> m_eval_ordered_nodes;
+  std::vector<std::vector<AnimGraphConnection> > m_node_input_connections;
+  std::vector<std::vector<AnimGraphConnection> > m_node_output_connections;
+
+  [[nodiscard]] const std::vector<AnimGraphConnection>&
+  GetGraphInputConnections() const {
+    return m_node_output_connections[1];
+  }
+
+  [[nodiscard]] const std::vector<AnimGraphConnection>&
+  GetGraphOutputConnections() const {
+    return m_node_input_connections[0];
+  }
+
+  std::vector<AnimData*> m_animdata_blocks;
+  NodeDescriptorBase* m_node_descriptor = nullptr;
+  char* m_input_buffer = nullptr;
+  char* m_output_buffer = nullptr;
+  char* m_connection_data_storage = nullptr;
+  char* m_const_node_inputs = nullptr;
+
+  std::vector<Socket>& GetGraphOutputs() { return m_node_descriptor->m_inputs; }
+  std::vector<Socket>& GetGraphInputs() { return m_node_descriptor->m_outputs; }
+
+  AnimDataAllocator m_anim_data_allocator;
+
+  ~AnimGraphBlendTree() override { dealloc(); }
+
+  void StartUpdateTick() { m_tick_number++; }
+
+  // AnimNode overrides
+  bool Init(AnimGraphContext& context) override;
+  void MarkActiveInputs(
+      const std::vector<AnimGraphConnection>& input_connections) override;
+  void CalcSyncTrack(
+      const std::vector<AnimGraphConnection>& input_connections) override;
+  void UpdateTime(float time_last, float time_now) override;
+  void Evaluate(AnimGraphContext& context) override;
+
+  void PropagateTimeToNodeInputs(const AnimNode* node);
+
+  void dealloc() {
+    for (size_t i = 0; i < m_animdata_blocks.size(); i++) {
+      m_animdata_blocks[i]->m_local_matrices.vector::~vector();
+    }
+    m_animdata_blocks.clear();
+
+    m_node_input_connections.clear();
+    m_node_output_connections.clear();
+
+    delete[] m_input_buffer;
+    delete[] m_output_buffer;
+    delete[] m_connection_data_storage;
+    delete[] m_const_node_inputs;
+
+    for (int i = 0; i < m_nodes.size(); i++) {
+      delete m_nodes[i];
+    }
+    m_nodes.clear();
+
+    delete m_node_descriptor;
+  }
+
+  void UpdateOrderedNodes();
+  void UpdateOrderedNodesRecursive(int node_index);
+  bool CheckIsNodeActive(AnimNode* node) {
+    return node->m_tick_number == m_tick_number;
+  }
+
+  void ResetNodeStates() {
+    for (size_t i = 0, n = m_nodes.size(); i < n; i++) {
+      m_nodes[i]->m_time_now = 0.f;
+      m_nodes[i]->m_time_last = 0.f;
+      m_nodes[i]->m_state = AnimNodeEvalState::Undefined;
+    }
+  }
+
+  const Socket* GetInputSocket(const std::string& name) const;
+  const Socket* GetOutputSocket(const std::string& name) const;
+
+  /** Sets the address that is used for the specified AnimGraph input Socket.
+   *
+   * @tparam T Type of the Socket.
+   * @param name Name of the Socket.
+   * @param value_ptr Pointer where the input is fetched during evaluation.
+   */
+  template <typename T>
+  void SetInput(const char* name, T* value_ptr) {
+    m_node_descriptor->SetOutput(name, value_ptr);
+
+    std::vector<size_t> connected_node_indices;
+
+    for (int i = 0; i < m_node_output_connections[1].size(); i++) {
+      const AnimGraphConnection& graph_input_connection =
+          m_node_output_connections[1][i];
+
+      if (graph_input_connection.m_source_socket_name == name) {
+        *graph_input_connection.m_socket.m_reference.ptr_ptr = value_ptr;
+      }
+    }
+  }
+
+  /** Sets the address that is used for the specified AnimGraph output Socket.
+   *
+   * We update the pointer of the outputting node. We also have to ensure that
+   * all usages of that output use the same pointer.
+   *
+   * @tparam T Type of the Socket.
+   * @param name Name of the Socket.
+   * @param value_ptr Pointer where the graph output output is written to at the end of evaluation.
+   */
+  template <typename T>
+  void SetOutput(const char* name, T* value_ptr) {
+    const auto& graph_output_connection = std::find_if(
+        GetGraphOutputConnections().begin(),
+        GetGraphOutputConnections().end(),
+        [&name](const AnimGraphConnection& connection) {
+          return connection.m_target_socket_name == name;
+        });
+
+    if (graph_output_connection == GetGraphOutputConnections().end()) {
+      std::cerr << "Error: could not find graph connection to output socket "
+                << name << "." << std::endl;
+      return;
+    }
+
+    if (graph_output_connection->m_source_node == m_nodes[1]
+        && graph_output_connection->m_target_node == m_nodes[0]) {
+      std::cerr << "Error: cannot set output for direct graph input to graph "
+                   "output connections. Use GetOutptPtr for output instead!"
+                << std::endl;
+
+      return;
+    }
+
+    size_t output_node_index =
+        GetAnimNodeIndex(graph_output_connection->m_source_node);
+
+    const std::vector<AnimGraphConnection>& node_output_connections =
+        m_node_output_connections[output_node_index];
+    for (const AnimGraphConnection& connection : node_output_connections) {
+      if (connection.m_source_socket_name
+          == graph_output_connection->m_source_socket_name) {
+        *connection.m_socket.m_reference.ptr_ptr = value_ptr;
+      }
+    }
+
+    *graph_output_connection->m_socket.m_reference.ptr_ptr = value_ptr;
+  }
+
+  /** Returns the address that is used for the specified AnimGraph output Socket.
+   *
+   * This function is needed for connections that directly connect an AnimGraph
+   * input Socket to an output Socket of the same AnimGraph.
+   *
+   * @tparam T Type of the Socket.
+   * @param name Name of the Socket.
+   * @return Address that is used for the specified AnimGraph output Socket.
+   */
+  template <typename T>
+  T* GetOutputPtr(const char* name) {
+    for (int i = 0; i < m_node_input_connections[0].size(); i++) {
+      const AnimGraphConnection& graph_output_connection =
+          m_node_input_connections[0][i];
+      if (graph_output_connection.m_target_socket_name == name) {
+        return static_cast<T*>(
+            *graph_output_connection.m_socket.m_reference.ptr_ptr);
+      }
+    }
+
+    return nullptr;
+  }
+
+  int GetAnimNodeIndex(const AnimNode* node) const {
+    for (int i = 0; i < m_nodes.size(); i++) {
+      if (m_nodes[i] == node) {
+        return i;
+      }
+    }
+
+    return -1;
+  }
+};
+
+//
+// BlendTreeSocketNode
+//
+struct BlendTreeSocketNode : public AnimNode {};
+
+template <>
+struct NodeDescriptor<BlendTreeSocketNode> : public NodeDescriptorBase {
+  NodeDescriptor(BlendTreeSocketNode* node_) {}
+};
+
+#endif  //ANIMTESTBED_ANIMGRAPHBLENDTREE_H

src/AnimGraph/AnimGraphData.h

@@ -22,8 +22,8 @@
 //
 // Data types
 //
-
 struct AnimGraph;
+struct AnimNode;
 
 struct AnimData {
   ozz::vector<ozz::math::SoaTransform> m_local_matrices;
@@ -161,7 +161,7 @@ struct Socket {
   SocketValue m_value = {0};
   std::string m_value_string;
   union SocketReference {
-    void* ptr;
+    void* ptr = nullptr;
     void** ptr_ptr;
   };
   SocketReference m_reference = {0};
@@ -260,6 +260,15 @@ SocketType GetSocketType() {
   return SocketType::SocketTypeUndefined;
 }
 
+struct AnimGraphConnection {
+  AnimNode* m_source_node = nullptr;
+  std::string m_source_socket_name = "";
+  AnimNode* m_target_node = nullptr;
+  std::string m_target_socket_name = "";
+  Socket m_socket;
+  bool m_crosses_hierarchy = false;
+};
+
 struct NodeDescriptorBase {
   std::vector<Socket> m_inputs;
   std::vector<Socket> m_outputs;
@@ -311,6 +320,13 @@ struct NodeDescriptorBase {
     return *socket->m_reference.ptr_ptr;
   }
 
+  template <typename T>
+  T GetInputValue(const char* name) const {
+    const Socket* socket = FindSocket(name, m_inputs);
+    assert(GetSocketType<T>() == socket->m_type);
+    return socket->GetValue<T>();
+  }
+
   template <typename T>
   void SetInput(const char* name, T* value_ptr) {
     Socket* socket = FindSocket(name, m_inputs);
@@ -402,7 +418,7 @@ struct NodeDescriptorBase {
     return socket->GetValue<T>();
   }
 
-  virtual void UpdateFlags(){};
+  virtual void UpdateFlags() {};
 
  protected:
   Socket* FindSocket(const char* name, std::vector<Socket>& sockets) {
@@ -415,6 +431,17 @@ struct NodeDescriptorBase {
     return nullptr;
   }
 
+  const Socket* FindSocket(const char* name, const std::vector<Socket>& sockets)
+      const {
+    for (int i = 0, n = sockets.size(); i < n; i++) {
+      if (sockets[i].m_name == name) {
+        return &sockets[i];
+      }
+    }
+
+    return nullptr;
+  }
+
   int FindSocketIndex(const char* name, std::vector<Socket>& sockets) {
     for (int i = 0, n = sockets.size(); i < n; i++) {
       if (sockets[i].m_name == name) {

src/AnimGraph/AnimGraphEditor.cc

@@ -13,8 +13,17 @@
 #include "imnodes.h"
 #include "misc/cpp/imgui_stdlib.h"
 
-static AnimGraphResource sGraphGresource = AnimGraphResource();
-static bool sGraphLoadedThisFrame = false;
+struct EditorState {
+  AnimGraphResource* rootGraphResource = nullptr;
+
+  std::vector<AnimGraphResource*> hierarchyStack;
+  size_t hierarchyStackIndex = 0;
+
+  bool isGraphLoadedThisFrame = false;
+  ImVec2 mousePopupStart = {};
+};
+
+static EditorState sEditorState;
 
 ImNodesPinShape sGetSocketShapeFromSocketType(const SocketType& socket_type) {
   switch (socket_type) {
@@ -37,44 +46,41 @@ ImNodesPinShape sGetSocketShapeFromSocketType(const SocketType& socket_type) {
   return ImNodesPinShape_Quad;
 }
 
-int GetNodeInputSocketId(int node_index, int input_socket_index) {
-  return node_index * 1000 + input_socket_index;
-}
-
-int GetNodeOutputSocketId(int node_index, int output_socket_index) {
-  return node_index * 1000 + 100 + output_socket_index;
-}
-
-void NodeSocketEditor(Socket& socket) {
+bool NodeSocketEditor(Socket& socket) {
+  bool modified = false;
   int mode_current = static_cast<int>(socket.m_type);
-  ImGui::InputText("Name", &socket.m_name);
+  if (ImGui::InputText("Name", &socket.m_name)) {
+    modified = true;
+  }
   if (ImGui::Combo(
           "Type",
           &mode_current,
           SocketTypeNames,
           sizeof(SocketTypeNames) / sizeof(char*))) {
     socket.m_type = static_cast<SocketType>(mode_current);
+
+    modified = true;
   }
+
+  return modified;
 }
 
-void RemoveConnectionsForSocket(
-    AnimGraphResource& graph_resource,
-    AnimNodeResource& node_resource,
+void RemoveBlendTreeConnectionsForSocket(
+    BlendTreeResource& blend_tree_resource,
+    AnimNodeResource* node_resource,
     Socket& socket) {
-  std::vector<AnimGraphConnectionResource>::iterator iter =
-      graph_resource.m_connections.begin();
+  const BlendTreeConnectionResource* connection =
+      blend_tree_resource.FindConnectionForSocket(node_resource, socket.m_name);
+  while (connection != nullptr) {
+    blend_tree_resource.DisconnectSockets(
+        blend_tree_resource.GetNode(connection->source_node_index),
+        connection->source_socket_name,
+        blend_tree_resource.GetNode(connection->target_node_index),
+        connection->target_socket_name);
 
-  while (iter != graph_resource.m_connections.end()) {
-    // TODO adjust for refactor
-    assert(false);
-
-    //    AnimGraphConnectionResource& connection = *iter;
-    //    if (connection.m_source_node == &node_resource
-    //        && connection.m_source_socket == &socket) {
-    //      iter = sGraphGresource.m_connections.erase(iter);
-    //    } else {
-    //      iter++;
-    //    }
+    connection = blend_tree_resource.FindConnectionForSocket(
+        node_resource,
+        socket.m_name);
   }
 }
 
@@ -159,24 +165,31 @@ void SkinnedMeshWidget(SkinnedMesh* skinned_mesh) {
 }
 
 void AnimGraphEditorRenderSidebar(
-    AnimGraphResource& graph_resource,
-    AnimNodeResource& node_resource) {
-  ImGui::Text("[%s]", node_resource.m_type_name.c_str());
+    BlendTreeResource& blend_tree_resource,
+    AnimNodeResource* node_resource) {
+  ImGui::Text(
+      "[%s (%2.2f, %2.2f)]",
+      node_resource->m_node_type_name.c_str(),
+      node_resource->m_position[0],
+      node_resource->m_position[1]);
 
   char node_name_buffer[256];
   memset(node_name_buffer, 0, sizeof(node_name_buffer));
   strncpy(
       node_name_buffer,
-      node_resource.m_name.c_str(),
-      std::min(node_resource.m_name.size(), sizeof(node_name_buffer)));
+      node_resource->m_name.c_str(),
+      std::min(node_resource->m_name.size(), sizeof(node_name_buffer)));
 
   if (ImGui::InputText("Name", node_name_buffer, sizeof(node_name_buffer))) {
-    node_resource.m_name = node_name_buffer;
+    node_resource->m_name = node_name_buffer;
   }
 
-  int num_properties = node_resource.m_socket_accessor->m_properties.size();
+  int num_properties = 0;
+  if (node_resource->m_socket_accessor != nullptr) {
+    num_properties = node_resource->m_socket_accessor->m_properties.size();
+  }
   for (int i = 0; i < num_properties; i++) {
-    Socket& property = node_resource.m_socket_accessor->m_properties[i];
+    Socket& property = node_resource->m_socket_accessor->m_properties[i];
     if (property.m_type == SocketType::SocketTypeInt) {
       ImGui::InputInt(
           property.m_name.c_str(),
@@ -211,223 +224,360 @@ void AnimGraphEditorRenderSidebar(
     }
   }
 
-  if (&node_resource == &graph_resource.getGraphOutputNode()) {
+  if (node_resource == blend_tree_resource.GetGraphOutputNode()) {
     ImGui::Text("Outputs");
 
     // Graph outputs are the inputs of the output node!
-    std::vector<Socket>& outputs = node_resource.m_socket_accessor->m_inputs;
+    std::vector<Socket>& outputs = node_resource->m_socket_accessor->m_inputs;
 
     std::vector<Socket>::iterator iter = outputs.begin();
     while (iter != outputs.end()) {
       Socket& output = *iter;
       ImGui::PushID(&output);
-      NodeSocketEditor(output);
+      if (NodeSocketEditor(output)) {
+        AnimGraphResource* current_graph_resource =
+            sEditorState.hierarchyStack[sEditorState.hierarchyStackIndex];
+        current_graph_resource->m_socket_accessor->m_inputs = outputs;
+      }
+
       if (ImGui::Button("X")) {
-        RemoveConnectionsForSocket(graph_resource, node_resource, output);
+        RemoveBlendTreeConnectionsForSocket(
+            blend_tree_resource,
+            node_resource,
+            output);
         iter = outputs.erase(iter);
       } else {
         iter++;
       }
       ImGui::PopID();
     }
+
+    if (ImGui::Button("+")) {
+      AnimGraphResource* current_graph_resource =
+          sEditorState.hierarchyStack[sEditorState.hierarchyStackIndex];
+      current_graph_resource->RegisterBlendTreeOutputSocket<float>(
+          "GraphFloatOutput");
+    }
   }
 
-  if (&node_resource == &graph_resource.getGraphInputNode()) {
+  if (node_resource == blend_tree_resource.GetGraphInputNode()) {
     ImGui::Text("Inputs");
 
     // Graph inputs are the outputs of the input node!
-    std::vector<Socket>& inputs = node_resource.m_socket_accessor->m_outputs;
+    std::vector<Socket>& inputs = node_resource->m_socket_accessor->m_outputs;
 
     std::vector<Socket>::iterator iter = inputs.begin();
     while (iter != inputs.end()) {
       Socket& input = *iter;
       ImGui::PushID(&input);
-      NodeSocketEditor(input);
+      if (NodeSocketEditor(input)) {
+        AnimGraphResource* current_graph_resource =
+            sEditorState.hierarchyStack[sEditorState.hierarchyStackIndex];
+        current_graph_resource->m_socket_accessor->m_inputs = inputs;
+      }
       if (ImGui::Button("X")) {
-        RemoveConnectionsForSocket(graph_resource, node_resource, input);
+        RemoveBlendTreeConnectionsForSocket(
+            blend_tree_resource,
+            node_resource,
+            input);
         iter = inputs.erase(iter);
       } else {
         iter++;
       }
       ImGui::PopID();
     }
+
+    if (ImGui::Button("+")) {
+      AnimGraphResource* current_graph_resource =
+          sEditorState.hierarchyStack[sEditorState.hierarchyStackIndex];
+      current_graph_resource->RegisterBlendTreeInputSocket<float>(
+          "GraphFloatInput");
+    }
   }
 }
 
+void AnimGraphEditorClear() {
+  if (ax::NodeEditor::GetCurrentEditor() != nullptr) {
+    ax::NodeEditor::ClearSelection();
+  }
+
+  if (sEditorState.rootGraphResource) {
+    delete sEditorState.rootGraphResource->m_socket_accessor;
+  }
+  delete sEditorState.rootGraphResource;
+
+  sEditorState.rootGraphResource = new AnimGraphResource();
+  sEditorState.rootGraphResource->m_name = "Root";
+  sEditorState.rootGraphResource->m_graph_type_name = "BlendTree";
+  sEditorState.rootGraphResource->m_blend_tree_resource.InitGraphConnectors();
+  sEditorState.rootGraphResource->m_socket_accessor = new NodeDescriptorBase;
+
+  sEditorState.hierarchyStack.clear();
+  sEditorState.hierarchyStack.push_back(sEditorState.rootGraphResource);
+  sEditorState.hierarchyStack[sEditorState.hierarchyStackIndex] =
+      sEditorState.hierarchyStack.back();
+  sEditorState.hierarchyStackIndex = 0;
+}
+
 void AnimGraphEditorUpdate(ax::NodeEditor::EditorContext* context) {
-  ImGui::BeginMenuBar();
-  if (ImGui::Button("Save")) {
-    sGraphGresource.saveToFile("editor_graph.json");
-  }
-  if (ImGui::Button("Load")) {
-    sGraphGresource.loadFromFile("editor_graph.json");
-    sGraphLoadedThisFrame = true;
-
-    //    for (size_t i = 0, n = sGraphGresource.m_nodes.size(); i < n; i++) {
-    //      const AnimNodeResource& node_resource = sGraphGresource.m_nodes[i];
-    //      ImNodes::SetNodeGridSpacePos(
-    //          i,
-    //          ImVec2(node_resource.m_position[0], node_resource.m_position[1]));
-    //    }
-  }
-  if (ImGui::Button("Clear")) {
-    sGraphGresource.clear();
-  }
-  char graph_name_buffer[256];
-  memset(graph_name_buffer, 0, sizeof(graph_name_buffer));
-  strncpy(
-      graph_name_buffer,
-      sGraphGresource.m_name.c_str(),
-      sizeof(graph_name_buffer));
-  if (ImGui::InputText("Name", graph_name_buffer, sizeof(graph_name_buffer))) {
-    sGraphGresource.m_name = graph_name_buffer;
-  }
-
-  ImGui::EndMenuBar();
-
-  //
-  // Node editor canvas
-  //
   ax::NodeEditor::SetCurrentEditor(context);
-  ax::NodeEditor::Begin("Graph Editor");
 
-#if 1
-  for (size_t node_id = 0, n = sGraphGresource.m_nodes.size(); node_id < n;
-       node_id++) {
-    AnimNodeResource& node_resource = sGraphGresource.m_nodes[node_id];
-
-    if (node_id == 0 || node_id == 1) {
-      // continue;
-    }
-
-    if (sGraphLoadedThisFrame) {
-      ax::NodeEditor::SetNodePosition(
-          node_id,
-          ImVec2(node_resource.m_position[0], node_resource.m_position[1]));
-    }
-    ax::NodeEditor::BeginNode(node_id);
-    ImGui::Text("%s", node_resource.m_type_name.c_str());
-
-    // Inputs
-    std::vector<Socket>& node_inputs =
-        node_resource.m_socket_accessor->m_inputs;
-    for (size_t j = 0, ni = node_inputs.size(); j < ni; j++) {
-      Socket& socket = node_inputs[j];
-      ax::NodeEditor::BeginPin(
-          GetNodeInputSocketId(static_cast<int>(node_id), static_cast<int>(j)),
-          ax::NodeEditor::PinKind::Input);
-      ImGui::Text("%s", socket.m_name.c_str());
-      ax::NodeEditor::EndPin();
-    }
-
-    // Outputs
-    std::vector<Socket>& node_outputs =
-        node_resource.m_socket_accessor->m_outputs;
-    for (size_t j = 0, ni = node_outputs.size(); j < ni; j++) {
-      Socket& socket = node_outputs[j];
-      ax::NodeEditor::BeginPin(
-          GetNodeOutputSocketId(static_cast<int>(node_id), static_cast<int>(j)),
-          ax::NodeEditor::PinKind::Output);
-      ImGui::Text("%s", socket.m_name.c_str());
-      ax::NodeEditor::EndPin();
-    }
-
-    ax::NodeEditor::EndNode();
-  }
-
-  int link_id = 0;
-  for (size_t connection_id = 0, n = sGraphGresource.m_connections.size(); connection_id < n;
-       connection_id++) {
-    const AnimGraphConnectionResource& connection_resource = sGraphGresource.m_connections[connection_id];
-
-    const AnimNodeResource& source_node_resource = sGraphGresource.m_nodes[connection_resource.source_node_index];
-    int source_socket_index = source_node_resource.m_socket_accessor->GetOutputIndex(connection_resource.source_socket_name.c_str());
-
-    const AnimNodeResource& target_node_resource = sGraphGresource.m_nodes[connection_resource.target_node_index];
-    int target_socket_index = target_node_resource.m_socket_accessor->GetInputIndex(connection_resource.target_socket_name.c_str());
-
-    int source_socket_id = GetNodeOutputSocketId(static_cast<int>(connection_resource.source_node_index), source_socket_index);
-    int target_socket_id = GetNodeInputSocketId(static_cast<int>(connection_resource.target_node_index), target_socket_index);
-
-    ax::NodeEditor::Link(link_id++, source_socket_id, target_socket_id);
-  }
-
-
-#endif
-
-
-#if 1
-  // Create Connections
-  if (ax::NodeEditor::BeginCreate()) {
-    ax::NodeEditor::PinId input_pin_id, output_pin_id;
-    if (ax::NodeEditor::QueryNewLink(&input_pin_id, &output_pin_id)) {
-      if (input_pin_id && output_pin_id) {
-        if (ax::NodeEditor::AcceptNewItem()) {
-        }
-      }
-    }
-  }
-  ax::NodeEditor::EndCreate();
-#endif
-
-  ax::NodeEditor::End();
-
-  sGraphLoadedThisFrame = false;
-
-  ax::NodeEditor::SetCurrentEditor(nullptr);
-}
-
-void LegacyAnimGraphEditorUpdate() {
+  //
+  // Menu bar
+  //
   ImGui::BeginMenuBar();
   if (ImGui::Button("Save")) {
-    sGraphGresource.saveToFile("editor_graph.json");
+    sEditorState.rootGraphResource->SaveToFile("editor_graph.json");
   }
   if (ImGui::Button("Load")) {
-    sGraphGresource.loadFromFile("editor_graph.json");
-
-    for (size_t i = 0, n = sGraphGresource.m_nodes.size(); i < n; i++) {
-      const AnimNodeResource& node_resource = sGraphGresource.m_nodes[i];
-      ImNodes::SetNodeGridSpacePos(
-          i,
-          ImVec2(node_resource.m_position[0], node_resource.m_position[1]));
-    }
+    AnimGraphEditorClear();
+    sEditorState.rootGraphResource->LoadFromFile("editor_graph.json");
+    sEditorState.isGraphLoadedThisFrame = true;
   }
   if (ImGui::Button("Clear")) {
-    sGraphGresource.clear();
+    AnimGraphEditorClear();
+  }
+  if (ImGui::Button("Content")) {
+    ax::NodeEditor::NavigateToContent();
   }
   char graph_name_buffer[256];
   memset(graph_name_buffer, 0, sizeof(graph_name_buffer));
   strncpy(
       graph_name_buffer,
-      sGraphGresource.m_name.c_str(),
+      sEditorState.hierarchyStack[sEditorState.hierarchyStackIndex]
+          ->m_name.c_str(),
       sizeof(graph_name_buffer));
   if (ImGui::InputText("Name", graph_name_buffer, sizeof(graph_name_buffer))) {
-    sGraphGresource.m_name = graph_name_buffer;
+    sEditorState.hierarchyStack[sEditorState.hierarchyStackIndex]->m_name =
+        graph_name_buffer;
   }
 
   ImGui::EndMenuBar();
 
+  //
+  // Breadcrumb navigation
+  //
+  for (size_t i = 0, n = sEditorState.hierarchyStack.size(); i < n; i++) {
+    AnimGraphResource* graph_resource =
+        dynamic_cast<AnimGraphResource*>(sEditorState.hierarchyStack[i]);
+    ImGui::PushID(graph_resource);
+
+    bool highlight_button = i == sEditorState.hierarchyStackIndex;
+
+    if (highlight_button) {
+      ImGui::PushStyleColor(
+          ImGuiCol_Button,
+          (ImVec4)ImColor::HSV(1. / 7.0f, 0.6f, 0.6f));
+    }
+
+    if (ImGui::Button(graph_resource->m_name.c_str())) {
+      sEditorState.hierarchyStackIndex = i;
+    }
+
+    if (highlight_button) {
+      ImGui::PopStyleColor(1);
+    }
+
+    ImGui::PopID();
+
+    if (i < n - 1) {
+      ImGui::SameLine();
+    }
+  }
+
   ImGui::Columns(2);
 
   //
   // Node editor canvas
   //
-  ImNodes::BeginNodeEditor();
+  ax::NodeEditor::Begin("Graph Editor");
+
+  for (size_t node_index = 0,
+              n = sEditorState.hierarchyStack[sEditorState.hierarchyStackIndex]
+                      ->m_blend_tree_resource.GetNumNodes();
+       node_index < n;
+       node_index++) {
+    AnimNodeResource* node_resource =
+        sEditorState.hierarchyStack[sEditorState.hierarchyStackIndex]
+            ->m_blend_tree_resource.GetNode(node_index);
+    ax::NodeEditor::NodeId node_id(node_resource);
+
+    if (sEditorState.isGraphLoadedThisFrame) {
+      ax::NodeEditor::SetNodePosition(
+          node_id,
+          ImVec2(node_resource->m_position[0], node_resource->m_position[1]));
+    }
+    ax::NodeEditor::BeginNode(node_id);
+    ImGui::Text("%s", node_resource->m_node_type_name.c_str());
+
+    // Inputs
+    std::vector<Socket> node_inputs =
+        sEditorState.hierarchyStack[sEditorState.hierarchyStackIndex]
+            ->m_blend_tree_resource.GetNodeInputSockets(node_resource);
+    for (size_t j = 0, ni = node_inputs.size(); j < ni; j++) {
+      Socket& socket = node_inputs[j];
+      ax::NodeEditor::BeginPin(
+          NodeIndexAndSocketIndexToInputPinId(
+              static_cast<int>(node_index),
+              static_cast<int>(j)),
+          ax::NodeEditor::PinKind::Input);
+      ImGui::Text("%s", socket.m_name.c_str());
+      ax::NodeEditor::EndPin();
+    }
+
+    // Outputs
+    std::vector<Socket> node_outputs =
+        sEditorState.hierarchyStack[sEditorState.hierarchyStackIndex]
+            ->m_blend_tree_resource.GetNodeOutputSockets(node_resource);
+    for (size_t j = 0, ni = node_outputs.size(); j < ni; j++) {
+      Socket& socket = node_outputs[j];
+      ax::NodeEditor::BeginPin(
+          NodeIndexAndSocketIndexToOutputPinId(
+              static_cast<int>(node_index),
+              static_cast<int>(j)),
+          ax::NodeEditor::PinKind::Output);
+      ImGui::Text("%s", socket.m_name.c_str());
+      ax::NodeEditor::EndPin();
+    }
+
+    ax::NodeEditor::EndNode();
+
+    ImVec2 node_position = ax::NodeEditor::GetNodePosition(node_id);
+    node_resource->m_position[0] = node_position.x;
+    node_resource->m_position[1] = node_position.y;
+  }
+
+  int link_id = 0;
+  for (size_t connection_id = 0,
+              n = sEditorState.hierarchyStack[sEditorState.hierarchyStackIndex]
+                      ->m_blend_tree_resource.GetNumConnections();
+       connection_id < n;
+       connection_id++) {
+    const BlendTreeConnectionResource* connection_resource =
+        sEditorState.hierarchyStack[sEditorState.hierarchyStackIndex]
+            ->m_blend_tree_resource.GetConnection(connection_id);
+
+    const AnimNodeResource* source_node_resource =
+        sEditorState.hierarchyStack[sEditorState.hierarchyStackIndex]
+            ->m_blend_tree_resource.GetNode(
+                connection_resource->source_node_index);
+    int source_socket_index =
+        source_node_resource->m_socket_accessor->GetOutputIndex(
+            connection_resource->source_socket_name.c_str());
+
+    const AnimNodeResource* target_node_resource =
+        sEditorState.hierarchyStack[sEditorState.hierarchyStackIndex]
+            ->m_blend_tree_resource.GetNode(
+                connection_resource->target_node_index);
+    int target_socket_index =
+        target_node_resource->m_socket_accessor->GetInputIndex(
+            connection_resource->target_socket_name.c_str());
+
+    int source_socket_pin_id = NodeIndexAndSocketIndexToOutputPinId(
+        static_cast<int>(connection_resource->source_node_index),
+        source_socket_index);
+    int target_socket_pin_id = NodeIndexAndSocketIndexToInputPinId(
+        static_cast<int>(connection_resource->target_node_index),
+        target_socket_index);
+
+    ax::NodeEditor::Link(
+        ax::NodeEditor::LinkId(connection_resource),
+        source_socket_pin_id,
+        target_socket_pin_id);
+  }
+
+  // Create Connections
+  if (ax::NodeEditor::BeginCreate()) {
+    ax::NodeEditor::PinId input_pin_id, output_pin_id;
+    if (ax::NodeEditor::QueryNewLink(&input_pin_id, &output_pin_id)) {
+      int source_node_index;
+      int source_node_socket_index;
+      const AnimNodeResource* source_node = nullptr;
+      const Socket* source_socket = nullptr;
+
+      if (input_pin_id) {
+        OutputPinIdToNodeIndexAndSocketIndex(
+            input_pin_id.Get(),
+            &source_node_index,
+            &source_node_socket_index);
+
+        source_node =
+            sEditorState.hierarchyStack[sEditorState.hierarchyStackIndex]
+                ->m_blend_tree_resource.GetNode(source_node_index);
+        if (source_node->m_socket_accessor->m_outputs.size()
+            < source_node_socket_index) {
+          source_node_socket_index = -1;
+        } else {
+          source_socket =
+              sEditorState.hierarchyStack[sEditorState.hierarchyStackIndex]
+                  ->m_blend_tree_resource.GetNodeOutputSocketByIndex(
+                      source_node,
+                      source_node_socket_index);
+        }
+      }
+
+      int target_node_index;
+      int target_node_socket_index;
+      const AnimNodeResource* target_node = nullptr;
+      const Socket* target_socket = nullptr;
+
+      if (output_pin_id) {
+        InputPinIdToNodeIndexAndSocketIndex(
+            output_pin_id.Get(),
+            &target_node_index,
+            &target_node_socket_index);
+
+        target_node =
+            sEditorState.hierarchyStack[sEditorState.hierarchyStackIndex]
+                ->m_blend_tree_resource.GetNode(target_node_index);
+        if (target_node->m_socket_accessor->m_inputs.size()
+            < target_node_socket_index) {
+          target_node_socket_index = -1;
+        } else {
+          target_socket =
+              sEditorState.hierarchyStack[sEditorState.hierarchyStackIndex]
+                  ->m_blend_tree_resource.GetNodeInputSocketByIndex(
+                      target_node,
+                      target_node_socket_index);
+        }
+      }
+
+      if (input_pin_id && output_pin_id) {
+        if (source_socket == nullptr || target_socket == nullptr
+            || !sEditorState.hierarchyStack[sEditorState.hierarchyStackIndex]
+                    ->m_blend_tree_resource.IsConnectionValid(
+                        source_node,
+                        source_socket->m_name,
+                        target_node,
+                        target_socket->m_name)) {
+          ax::NodeEditor::RejectNewItem();
+        } else if (ax::NodeEditor::AcceptNewItem()) {
+          sEditorState.hierarchyStack[sEditorState.hierarchyStackIndex]
+              ->m_blend_tree_resource.ConnectSockets(
+                  source_node,
+                  source_socket->m_name,
+                  target_node,
+                  target_socket->m_name);
+        }
+      }
+    }
+  }
+  ax::NodeEditor::EndCreate();
 
   // Popup menu
   {
-    const bool open_popup =
-        ImGui::IsWindowFocused(ImGuiFocusedFlags_RootAndChildWindows)
-        && ImNodes::IsEditorHovered()
-        && ImGui::IsMouseReleased(ImGuiMouseButton_Right);
+    const bool open_popup = ImGui::IsMouseReleased(ImGuiMouseButton_Right);
 
-    ImGui::PushStyleVar(ImGuiStyleVar_WindowPadding, ImVec2(8.f, 8.f));
-    if (!ImGui::IsAnyItemHovered() && open_popup) {
+    if (open_popup && ImGui::IsWindowHovered()) {
+      ax::NodeEditor::Suspend();
       ImGui::OpenPopup("add node");
+      ax::NodeEditor::Resume();
+      sEditorState.mousePopupStart = ImGui::GetMousePos();
     }
 
+    ax::NodeEditor::Suspend();
+    ImGui::PushStyleVar(ImGuiStyleVar_WindowPadding, ImVec2(8.f, 8.f));
     if (ImGui::BeginPopup("add node")) {
-      const ImVec2 click_pos = ImGui::GetMousePosOnOpeningCurrentPopup();
       std::string node_type_name = "";
       if (ImGui::MenuItem("AnimSampler")) {
         node_type_name = "AnimSampler";
@@ -457,226 +607,108 @@ void LegacyAnimGraphEditorUpdate() {
         node_type_name = "ConstScalarNode";
       }
 
-      if (node_type_name != "") {
-        AnimNodeResource node_resource =
+      if (ImGui::MenuItem("BlendTree")) {
+        node_type_name = "BlendTree";
+      }
+
+      if (!node_type_name.empty()) {
+        AnimNodeResource* node_resource =
             AnimNodeResourceFactory(node_type_name);
-        size_t node_id = sGraphGresource.m_nodes.size();
-        ImNodes::SetNodeScreenSpacePos(node_id, ImGui::GetMousePos());
-        sGraphGresource.m_nodes.push_back(node_resource);
+        ax::NodeEditor::SetNodePosition(
+            ax::NodeEditor::NodeId(node_resource),
+            sEditorState.mousePopupStart);
+        sEditorState.hierarchyStack[sEditorState.hierarchyStackIndex]
+            ->m_blend_tree_resource.AddNode(node_resource);
       }
 
       ImGui::EndPopup();
     }
-
-    ImGui::PopStyleVar(ImGuiStyleVar_WindowPadding);
+    ImGui::PopStyleVar();
+    ax::NodeEditor::Resume();
   }
 
-  for (size_t i = 0, n = sGraphGresource.m_nodes.size(); i < n; i++) {
-    AnimNodeResource& node_resource = sGraphGresource.m_nodes[i];
-
-    ImNodes::BeginNode(i);
-    ImGui::PushItemWidth(110.0f);
-
-    // Header
-    ImNodes::BeginNodeTitleBar();
-    if (&node_resource == &sGraphGresource.getGraphOutputNode()) {
-      ImGui::TextUnformatted("Graph Outputs");
-    } else if (&node_resource == &sGraphGresource.getGraphInputNode()) {
-      ImGui::TextUnformatted("Graph Inputs");
-    } else {
-      ImGui::TextUnformatted(node_resource.m_type_name.c_str());
-    }
-    ImNodes::EndNodeTitleBar();
-
-    // Inputs
-    std::vector<Socket>& node_inputs =
-        node_resource.m_socket_accessor->m_inputs;
-    for (size_t j = 0, ni = node_inputs.size(); j < ni; j++) {
-      Socket& socket = node_inputs[j];
-
-      ImColor socket_color = ImColor(255, 255, 255, 255);
-      if (socket.m_flags & SocketFlagAffectsTime) {
-        socket_color = ImColor(255, 128, 128, 255);
-      }
-
-      ImNodes::BeginInputAttribute(
-          GenerateInputAttributeId(i, j),
-          sGetSocketShapeFromSocketType(socket.m_type),
-          socket_color);
-      ImGui::TextUnformatted(socket.m_name.c_str());
-
-      bool socket_connected =
-          sGraphGresource.isSocketConnected(node_resource, socket.m_name);
-      if (!socket_connected && (socket.m_type == SocketType::SocketTypeFloat)) {
-        ImGui::SameLine();
-        float socket_value = socket.m_value.float_value;
-        ImGui::PushItemWidth(
-            130.0f - ImGui::CalcTextSize(socket.m_name.c_str()).x);
-        if (ImGui::DragFloat("##hidelabel", &socket_value, 0.01f)) {
-          socket.SetValue(socket_value);
-        }
-        ImGui::PopItemWidth();
-      }
-
-      if (!socket_connected && (socket.m_type == SocketType::SocketTypeInt)) {
-        ImGui::SameLine();
-        int socket_value = socket.m_value.int_value;
-        ImGui::PushItemWidth(
-            130.0f - ImGui::CalcTextSize(socket.m_name.c_str()).x);
-        if (ImGui::InputInt("##hidelabel", &socket_value, 1)) {
-          socket.SetValue(socket_value);
-        }
-        ImGui::PopItemWidth();
-      }
-
-      ImNodes::PushAttributeFlag(
-          ImNodesAttributeFlags_EnableLinkDetachWithDragClick);
-      ImNodes::EndInputAttribute();
-    }
-
-    // Outputs
-    const std::vector<Socket>& node_outputs =
-        node_resource.m_socket_accessor->m_outputs;
-    for (size_t j = 0, ni = node_outputs.size(); j < ni; j++) {
-      const Socket& socket = node_outputs[j];
-      ImNodes::BeginOutputAttribute(
-          GenerateOutputAttributeId(i, j),
-          sGetSocketShapeFromSocketType(socket.m_type),
-          ImColor(255, 255, 255, 255));
-      ImGui::TextUnformatted(socket.m_name.c_str());
-      ImNodes::PushAttributeFlag(
-          ImNodesAttributeFlags_EnableLinkDetachWithDragClick);
-      ImNodes::EndInputAttribute();
-    }
-
-    // Graph output node
-    if (i == 0) {
-      if (ImGui::Button("+Output")) {
-        AnimNodeResource& graph_output_node =
-            sGraphGresource.getGraphOutputNode();
-
-        static float bla = 0.f;
-        std::string socket_name = "Output";
-        socket_name += std::to_string(
-            graph_output_node.m_socket_accessor->m_inputs.size());
-        graph_output_node.m_socket_accessor->RegisterInput<float>(
-            socket_name.c_str(),
-            nullptr);
-      }
-    } else if (i == 1) {
-      if (ImGui::Button("+Input")) {
-        AnimNodeResource& graph_input_node =
-            sGraphGresource.getGraphInputNode();
-
-        static float bla = 0.f;
-        std::string socket_name = "Input";
-        socket_name += std::to_string(
-            graph_input_node.m_socket_accessor->m_outputs.size());
-        graph_input_node.m_socket_accessor->RegisterOutput<float>(
-            socket_name.c_str(),
-            nullptr);
-      }
-    }
-
-    // Save state in node resource
-    ImVec2 node_pos = ImNodes::GetNodeGridSpacePos(i);
-    node_resource.m_position[0] = node_pos[0];
-    node_resource.m_position[1] = node_pos[1];
-    ImGui::PopItemWidth();
-
-    ImNodes::EndNode();
-
-    // Ensure flags such as SocketFlagAffectsTime are properly set.
-    node_resource.m_socket_accessor->UpdateFlags();
-  }
-
-  for (size_t i = 0, n = sGraphGresource.m_connections.size(); i < n; i++) {
-    const AnimGraphConnectionResource& connection =
-        sGraphGresource.m_connections[i];
-    int start_attr, end_attr;
-
-    const AnimNodeResource& source_node =
-        sGraphGresource.m_nodes[connection.source_node_index];
-    int source_socket_index = source_node.m_socket_accessor->GetOutputIndex(
-        connection.source_socket_name.c_str());
-
-    const AnimNodeResource& target_node =
-        sGraphGresource.m_nodes[connection.target_node_index];
-    int target_socket_index = target_node.m_socket_accessor->GetInputIndex(
-        connection.target_socket_name.c_str());
-
-    start_attr = GenerateOutputAttributeId(
-        connection.source_node_index,
-        source_socket_index);
-    end_attr = GenerateInputAttributeId(
-        connection.target_node_index,
-        target_socket_index);
-
-    ImNodes::Link(i, start_attr, end_attr);
-  }
-
-  ImNodes::EndNodeEditor();
-
-  // Handle newly created links.
-  int start_attr, end_attr;
-  if (ImNodes::IsLinkCreated(&start_attr, &end_attr)) {
-    int node_start_id;
-    int node_start_output_index;
-    SplitOutputAttributeId(
-        start_attr,
-        &node_start_id,
-        &node_start_output_index);
-
-    int node_end_id;
-    int node_end_input_index;
-    SplitInputAttributeId(end_attr, &node_end_id, &node_end_input_index);
-
-    AnimGraphConnectionResource connection;
-    connection.source_node_index = node_start_id;
-    const AnimNodeResource& source_node =
-        sGraphGresource.m_nodes[node_start_id];
-    connection.source_socket_name =
-        source_node.m_socket_accessor->m_outputs[node_start_output_index]
-            .m_name;
-
-    connection.target_node_index = node_end_id;
-    const AnimNodeResource& target_node = sGraphGresource.m_nodes[node_end_id];
-    connection.target_socket_name =
-        target_node.m_socket_accessor->m_inputs[node_end_input_index].m_name;
-
-    sGraphGresource.m_connections.push_back(connection);
-  }
-
-  if (ImGui::IsKeyPressed(ImGuiKey_Delete, false)) {
-    std::cerr << "Delete key!" << std::endl;
-  }
-
-  // Handle link detachements.
-  int link_id = 0;
-  if (ImNodes::IsLinkDestroyed(&link_id)) {
-    sGraphGresource.m_connections.erase(
-        sGraphGresource.m_connections.begin() + link_id);
-  }
-
-  int selected_nodes[ImNodes::NumSelectedNodes()];
-  ImNodes::GetSelectedNodes(selected_nodes);
+  ax::NodeEditor::End();
 
   //
   // Sidebar
   //
   ImGui::NextColumn();
 
-  if (ImNodes::NumSelectedNodes() == 1) {
-    if (selected_nodes[0] < sGraphGresource.m_nodes.size()) {
-      AnimNodeResource& selected_node =
-          sGraphGresource.m_nodes[selected_nodes[0]];
-      AnimGraphEditorRenderSidebar(sGraphGresource, selected_node);
+  if (ax::NodeEditor::GetSelectedObjectCount() > 0) {
+    ax::NodeEditor::NodeId selected_node_id = 0;
+
+    ax::NodeEditor::GetSelectedNodes(&selected_node_id, 1);
+
+    if (selected_node_id.Get() != 0) {
+      AnimGraphEditorRenderSidebar(
+          sEditorState.hierarchyStack[sEditorState.hierarchyStackIndex]
+              ->m_blend_tree_resource,
+          selected_node_id.AsPointer<AnimNodeResource>());
     }
   }
 
   ImGui::Columns(1);
+
+  // Clear flag, however it may be re-set further down when handling double
+  // clicking into subgraphs.
+  sEditorState.isGraphLoadedThisFrame = false;
+
+  //
+  // Handle double click into subgraphs
+  //
+  ax::NodeEditor::NodeId double_clicked_node_id =
+      ax::NodeEditor::GetDoubleClickedNode();
+  if (!double_clicked_node_id.Invalid) {
+    AnimNodeResource* clicked_node_resource =
+        double_clicked_node_id.AsPointer<AnimNodeResource>();
+
+    if (clicked_node_resource != nullptr
+        && clicked_node_resource->m_node_type_name == "BlendTree") {
+      AnimGraphResource* clicked_graph_resource =
+          dynamic_cast<AnimGraphResource*>(clicked_node_resource);
+
+      assert(clicked_graph_resource != nullptr);
+
+      if (sEditorState.hierarchyStack.size()
+              > sEditorState.hierarchyStackIndex + 1
+          && sEditorState.hierarchyStack[sEditorState.hierarchyStackIndex + 1]
+                 == clicked_graph_resource) {
+        sEditorState.hierarchyStackIndex++;
+      } else {
+        sEditorState.hierarchyStack.resize(
+            sEditorState.hierarchyStackIndex + 1);
+        sEditorState.hierarchyStack.push_back(clicked_graph_resource);
+        sEditorState.hierarchyStackIndex++;
+      }
+
+      sEditorState.isGraphLoadedThisFrame = true;
+      ax::NodeEditor::ClearSelection();
+    }
+  }
+
+  ax::NodeEditor::LinkId hovered_link = ax::NodeEditor::GetHoveredLink();
+  if (!hovered_link.Invalid) {
+    BlendTreeConnectionResource* connection_resource =
+        hovered_link.AsPointer<BlendTreeConnectionResource>();
+
+    if (connection_resource && ImGui::IsKeyPressed(ImGuiKey_Delete)) {
+      BlendTreeResource* blend_tree_resource =
+          &sEditorState.hierarchyStack[sEditorState.hierarchyStackIndex]
+               ->m_blend_tree_resource;
+
+      blend_tree_resource->DisconnectSockets(
+          blend_tree_resource->GetNode(connection_resource->source_node_index),
+          connection_resource->source_socket_name,
+          blend_tree_resource->GetNode(connection_resource->target_node_index),
+          connection_resource->target_socket_name);
+
+      ax::NodeEditor::DeleteLink(hovered_link);
+    }
+  }
+
+  ax::NodeEditor::SetCurrentEditor(nullptr);
 }
 
-void AnimGraphEditorGetRuntimeGraph(AnimGraph& anim_graph) {
-  sGraphGresource.createInstance(anim_graph);
+void AnimGraphEditorGetRuntimeGraph(AnimGraphBlendTree& blend_tree) {
+  sEditorState.rootGraphResource->CreateBlendTreeInstance(blend_tree);
 }

src/AnimGraph/AnimGraphEditor.h

@@ -5,13 +5,13 @@
 #ifndef ANIMTESTBED_ANIMGRAPHEDITOR_H
 #define ANIMTESTBED_ANIMGRAPHEDITOR_H
 
-#include "AnimGraph.h"
-
 namespace ax::NodeEditor {
 struct EditorContext;
 }  // namespace ax::NodeEditor
 
 struct SkinnedMesh;
+struct AnimGraphBlendTree;
+struct SyncTrack;
 
 inline int GenerateInputAttributeId(int node_id, int input_index) {
   return ((input_index + 1) << 14) + node_id;
@@ -33,14 +33,42 @@ SplitOutputAttributeId(int attribute_id, int* node_id, int* output_index) {
   *output_index = (attribute_id >> 23) - 1;
 }
 
+inline int NodeIndexAndSocketIndexToInputPinId(
+    int node_index,
+    int input_socket_index) {
+  return node_index * 1000 + input_socket_index;
+}
+
+inline int NodeIndexAndSocketIndexToOutputPinId(
+    int node_index,
+    int output_socket_index) {
+  return node_index * 1000 + 500 + output_socket_index;
+}
+
+inline void InputPinIdToNodeIndexAndSocketIndex(
+    unsigned long input_pin_id,
+    int* node_index,
+    int* socket_index) {
+  *socket_index = input_pin_id % 1000;
+  *node_index = (input_pin_id - *socket_index) / 1000;
+}
+
+inline void OutputPinIdToNodeIndexAndSocketIndex(
+    unsigned long output_pin_id,
+    int* node_index,
+    int* socket_index) {
+  *socket_index = ((output_pin_id - 500) % 1000);
+  *node_index = (output_pin_id - *socket_index) / 1000;
+}
+
 void SyncTrackEditor(SyncTrack* sync_track);
 
 void SkinnedMeshWidget(SkinnedMesh* skinned_mesh);
 
+void AnimGraphEditorClear();
+
 void AnimGraphEditorUpdate(ax::NodeEditor::EditorContext* context);
 
-void LegacyAnimGraphEditorUpdate();
-
-void AnimGraphEditorGetRuntimeGraph(AnimGraph& anim_graph);
+void AnimGraphEditorGetRuntimeGraph(AnimGraphBlendTree& anim_graph);
 
 #endif  //ANIMTESTBED_ANIMGRAPHEDITOR_H

src/AnimGraph/AnimGraphNodes.cc

@@ -4,17 +4,77 @@
 
 #include "AnimGraphNodes.h"
 
-#include "ozz/base/log.h"
-#include "ozz/animation/runtime/blending_job.h"
+#include "AnimGraphBlendTree.h"
 #include "ozz/animation/runtime/animation.h"
+#include "ozz/animation/runtime/blending_job.h"
 #include "ozz/base/io/archive.h"
 #include "ozz/base/io/stream.h"
+#include "ozz/base/log.h"
+
+AnimNode* AnimNodeFactory(const std::string& name) {
+  AnimNode* result;
+  if (name == "Blend2") {
+    result = new Blend2Node;
+  } else if (name == "SpeedScale") {
+    result = new SpeedScaleNode;
+  } else if (name == "AnimSampler") {
+    result = new AnimSamplerNode;
+  } else if (name == "LockTranslationNode") {
+    result = new LockTranslationNode;
+  } else if (name == "BlendTree") {
+    result = new AnimGraphBlendTree;
+  } else if (name == "BlendTreeSockets") {
+    result = new BlendTreeSocketNode;
+  } else if (name == "MathAddNode") {
+    result = new MathAddNode;
+  } else if (name == "MathFloatToVec3Node") {
+    result = new MathFloatToVec3Node;
+  } else if (name == "ConstScalarNode") {
+    result = new ConstScalarNode;
+  }
+
+  if (result != nullptr) {
+    result->m_node_type_name = name;
+    return result;
+  }
+
+  std::cerr << "Invalid node type: " << name << std::endl;
+  return nullptr;
+}
+
+NodeDescriptorBase* AnimNodeDescriptorFactory(
+    const std::string& node_type_name,
+    AnimNode* node) {
+  if (node_type_name == "Blend2") {
+    return CreateNodeDescriptor<Blend2Node>(node);
+  } else if (node_type_name == "SpeedScale") {
+    return CreateNodeDescriptor<SpeedScaleNode>(node);
+  } else if (node_type_name == "AnimSampler") {
+    return CreateNodeDescriptor<AnimSamplerNode>(node);
+  } else if (node_type_name == "LockTranslationNode") {
+    return CreateNodeDescriptor<LockTranslationNode>(node);
+  } else if (node_type_name == "BlendTree") {
+    return CreateNodeDescriptor<BlendTreeSocketNode>(node);
+  } else if (node_type_name == "BlendTreeSockets") {
+    return CreateNodeDescriptor<BlendTreeSocketNode>(node);
+  } else if (node_type_name == "MathAddNode") {
+    return CreateNodeDescriptor<MathAddNode>(node);
+  } else if (node_type_name == "MathFloatToVec3Node") {
+    return CreateNodeDescriptor<MathFloatToVec3Node>(node);
+  } else if (node_type_name == "ConstScalarNode") {
+    return CreateNodeDescriptor<ConstScalarNode>(node);
+  } else {
+    std::cerr << "Invalid node type name " << node_type_name << "."
+              << std::endl;
+  }
+  return nullptr;
+}
 
 void Blend2Node::Evaluate(AnimGraphContext& context) {
-  assert (i_input0 != nullptr);
-  assert (i_input1 != nullptr);
-  assert (i_blend_weight != nullptr);
-  assert (o_output != nullptr);
+  assert(i_input0 != nullptr);
+  assert(i_input1 != nullptr);
+  assert(i_blend_weight != nullptr);
+  assert(o_output != nullptr);
 
   // perform blend
   ozz::animation::BlendingJob::Layer layers[2];
@@ -38,12 +98,10 @@ void Blend2Node::Evaluate(AnimGraphContext& context) {
 //
 // AnimSamplerNode
 //
-AnimSamplerNode::~AnimSamplerNode() noexcept {
-  m_animation = nullptr;
-}
+AnimSamplerNode::~AnimSamplerNode() noexcept { m_animation = nullptr; }
 
 bool AnimSamplerNode::Init(AnimGraphContext& context) {
-  assert (m_animation == nullptr);
+  assert(m_animation == nullptr);
   assert(!m_filename.empty());
 
   AnimGraphContext::AnimationFileMap::const_iterator animation_map_iter;
@@ -70,14 +128,14 @@ bool AnimSamplerNode::Init(AnimGraphContext& context) {
     context.m_animation_map[m_filename] = m_animation;
   }
 
-  assert (context.m_skeleton != nullptr);
+  assert(context.m_skeleton != nullptr);
   m_sampling_context.Resize(context.m_skeleton->num_joints());
 
   return true;
 }
 
 void AnimSamplerNode::Evaluate(AnimGraphContext& context) {
-  assert (o_output != nullptr);
+  assert(o_output != nullptr);
 
   ozz::animation::SamplingJob sampling_job;
   sampling_job.animation = m_animation;

src/AnimGraph/AnimGraphNodes.h

@@ -8,81 +8,12 @@
 #include <vector>
 
 #include "AnimGraphData.h"
+#include "AnimNode.h"
 #include "SyncTrack.h"
 #include "ozz/animation/runtime/sampling_job.h"
 
 struct AnimNode;
 
-enum class AnimNodeEvalState {
-  Undefined,
-  Deactivated,
-  Activated,
-  SyncTrackUpdated,
-  TimeUpdated,
-  Evaluated
-};
-
-struct AnimGraphConnection {
-  AnimNode* m_source_node = nullptr;
-  Socket m_source_socket;
-  AnimNode* m_target_node = nullptr;
-  Socket m_target_socket;
-};
-
-struct AnimNode {
-  std::string m_name;
-  std::string m_node_type_name;
-  float m_time_now = 0.f;
-  float m_time_last = 0.f;
-  size_t m_index = -1;
-  AnimNodeEvalState m_state = AnimNodeEvalState::Undefined;
-  SyncTrack m_sync_track;
-
-  virtual ~AnimNode() = default;
-
-  virtual bool Init(AnimGraphContext& context) { return true; };
-
-  virtual void MarkActiveInputs(const std::vector<AnimGraphConnection>& inputs) {
-    for (const auto & input : inputs) {
-      AnimNode* input_node = input.m_source_node;
-      if (input_node != nullptr) {
-        input_node->m_state = AnimNodeEvalState::Activated;
-      }
-    }
-  }
-
-  virtual void CalcSyncTrack(const std::vector<AnimGraphConnection>& inputs) {
-    for (const auto & input : inputs) {
-      AnimNode* input_node = input.m_source_node;
-      if (input_node != nullptr
-          && input.m_source_socket.m_type == SocketType::SocketTypeAnimation
-          && input_node->m_state != AnimNodeEvalState::Deactivated) {
-        m_sync_track = input_node->m_sync_track;
-        return;
-      }
-    }
-  }
-
-  virtual void UpdateTime(float time_last, float time_now) {
-    m_time_last = time_last;
-    m_time_now = time_now;
-    m_state = AnimNodeEvalState::TimeUpdated;
-  }
-
-  virtual void Evaluate(AnimGraphContext& context){};
-};
-
-
-//
-// BlendTreeNode
-//
-struct BlendTreeNode : public AnimNode {};
-
-template <>
-struct NodeDescriptor<BlendTreeNode> : public NodeDescriptorBase {
-  NodeDescriptor(BlendTreeNode* node_) {}
-};
-
 //
 // Blend2Node
 //
@@ -93,26 +24,27 @@ struct Blend2Node : public AnimNode {
   float* i_blend_weight = nullptr;
   bool m_sync_blend = false;
 
-  virtual void MarkActiveInputs(const std::vector<AnimGraphConnection>& inputs) override {
-    for (const auto & input : inputs) {
+  void MarkActiveInputs(
+      const std::vector<AnimGraphConnection>& input_connections) override {
+    for (const auto& input : input_connections) {
       AnimNode* input_node = input.m_source_node;
       if (input_node == nullptr) {
         continue;
       }
 
-      if (input.m_target_socket.m_name == "Input0" && *i_blend_weight < 0.999) {
+      if (input.m_target_socket_name == "Input0" && *i_blend_weight < 0.999) {
         input_node->m_state = AnimNodeEvalState::Activated;
         continue;
       }
 
-      if (input.m_target_socket.m_name == "Input1" && *i_blend_weight > 0.001) {
+      if (input.m_target_socket_name == "Input1" && *i_blend_weight > 0.001) {
         input_node->m_state = AnimNodeEvalState::Activated;
         continue;
       }
     }
   }
 
-  virtual void Evaluate(AnimGraphContext& context) override;
+  void Evaluate(AnimGraphContext& context) override;
 };
 
 template <>
@@ -139,7 +71,6 @@ struct NodeDescriptor<Blend2Node> : public NodeDescriptorBase {
   }
 };
 
-
 //
 // SpeedScaleNode
 //
@@ -155,8 +86,8 @@ struct SpeedScaleNode : public AnimNode {
   }
 
   void Evaluate(AnimGraphContext& context) override {
-    assert (i_input != nullptr);
-    assert (o_output != nullptr);
+    assert(i_input != nullptr);
+    assert(o_output != nullptr);
 
     o_output->m_local_matrices = i_input->m_local_matrices;
   };
@@ -175,7 +106,6 @@ struct NodeDescriptor<SpeedScaleNode> : public NodeDescriptorBase {
   }
 };
 
-
 //
 // AnimSamplerNode
 //
@@ -185,8 +115,8 @@ struct AnimSamplerNode : public AnimNode {
   ozz::animation::SamplingJob::Context m_sampling_context;
   ozz::animation::Animation* m_animation = nullptr;
 
-  virtual ~AnimSamplerNode();
-  virtual bool Init(AnimGraphContext& context) override;
+  ~AnimSamplerNode() noexcept override;
+  bool Init(AnimGraphContext& context) override;
   void UpdateTime(float time_last, float time_now) override {
     m_time_last = time_last;
     m_time_now = time_now;
@@ -231,7 +161,6 @@ struct NodeDescriptor<LockTranslationNode> : public NodeDescriptorBase {
   }
 };
 
-
 //
 // ConstScalarNode
 //
@@ -239,9 +168,7 @@ struct ConstScalarNode : public AnimNode {
   float* o_value = nullptr;
   float value = 0.f;
 
-  virtual void Evaluate(AnimGraphContext& context){
-    *o_value = value;
-  };
+  virtual void Evaluate(AnimGraphContext& context) { *o_value = value; };
 };
 
 template <>
@@ -252,7 +179,6 @@ struct NodeDescriptor<ConstScalarNode> : public NodeDescriptorBase {
   }
 };
 
-
 //
 // MathAddNode
 //
@@ -262,8 +188,8 @@ struct MathAddNode : public AnimNode {
   float* o_output = nullptr;
 
   void Evaluate(AnimGraphContext& context) override {
-    assert (i_input0 != nullptr);
-    assert (i_input1 != nullptr);
+    assert(i_input0 != nullptr);
+    assert(i_input1 != nullptr);
 
     *o_output = *i_input0 + *i_input1;
   }
@@ -288,9 +214,9 @@ struct MathFloatToVec3Node : public AnimNode {
   Vec3* o_output = nullptr;
 
   void Evaluate(AnimGraphContext& context) override {
-    assert (i_input0 != nullptr);
-    assert (i_input1 != nullptr);
-    assert (i_input2 != nullptr);
+    assert(i_input0 != nullptr);
+    assert(i_input1 != nullptr);
+    assert(i_input2 != nullptr);
 
     o_output->v[0] = *i_input0;
     o_output->v[1] = *i_input1;
@@ -308,60 +234,10 @@ struct NodeDescriptor<MathFloatToVec3Node> : public NodeDescriptorBase {
   }
 };
 
+AnimNode* AnimNodeFactory(const std::string& name);
 
-static inline AnimNode* AnimNodeFactory(const std::string& name) {
-  AnimNode* result;
-  if (name == "Blend2") {
-    result = new Blend2Node;
-  } else if (name == "SpeedScale") {
-    result = new SpeedScaleNode;
-  } else if (name == "AnimSampler") {
-    result = new AnimSamplerNode;
-  } else if (name == "LockTranslationNode") {
-    result = new LockTranslationNode;
-  } else if (name == "BlendTree") {
-    result = new BlendTreeNode;
-  } else if (name == "MathAddNode") {
-    result = new MathAddNode;
-  } else if (name == "MathFloatToVec3Node") {
-    result = new MathFloatToVec3Node;
-  } else if (name == "ConstScalarNode") {
-    result = new ConstScalarNode;
-  }
-
-  if (result != nullptr) {
-    result->m_node_type_name = name;
-    return result;
-  }
-
-  std::cerr << "Invalid node type: " << name << std::endl;
-  return nullptr;
-}
-
-static inline NodeDescriptorBase* AnimNodeDescriptorFactory(
+NodeDescriptorBase* AnimNodeDescriptorFactory(
     const std::string& node_type_name,
-    AnimNode* node) {
-  if (node_type_name == "Blend2") {
-    return CreateNodeDescriptor<Blend2Node>(node);
-  } else if (node_type_name == "SpeedScale") {
-    return CreateNodeDescriptor<SpeedScaleNode>(node);
-  } else if (node_type_name == "AnimSampler") {
-    return CreateNodeDescriptor<AnimSamplerNode>(node);
-  } else if (node_type_name == "LockTranslationNode") {
-    return CreateNodeDescriptor<LockTranslationNode>(node);
-  } else if (node_type_name == "BlendTree") {
-    return CreateNodeDescriptor<BlendTreeNode>(node);
-  } else if (node_type_name == "MathAddNode") {
-    return CreateNodeDescriptor<MathAddNode>(node);
-  } else if (node_type_name == "MathFloatToVec3Node") {
-    return CreateNodeDescriptor<MathFloatToVec3Node>(node);
-  } else if (node_type_name == "ConstScalarNode") {
-    return CreateNodeDescriptor<ConstScalarNode>(node);
-  } else {
-    std::cerr << "Invalid node type name " << node_type_name << "."
-              << std::endl;
-  }
-  return nullptr;
-}
+    AnimNode* node);
 
 #endif  //ANIMTESTBED_ANIMGRAPHNODES_H

src/AnimGraph/AnimGraphResource.h

@@ -1,146 +1,390 @@
 //
-// Created by martin on 04.02.22.
+// Created by martin on 17.03.24.
 //
 
 #ifndef ANIMTESTBED_ANIMGRAPHRESOURCE_H
 #define ANIMTESTBED_ANIMGRAPHRESOURCE_H
 
-#include <cstring>
-#include <iostream>
-#include <map>
-#include <string>
-#include <type_traits>
-#include <vector>
-
-#include "AnimGraph.h"
-#include "AnimGraphData.h"
+#include "3rdparty/json/json.hpp"
 #include "AnimGraphNodes.h"
-#include "SyncTrack.h"
 
-struct AnimNode;
+struct AnimGraphBlendTree;
+struct AnimGraphStateMachine;
 
 struct AnimNodeResource {
+  virtual ~AnimNodeResource() = default;
+
   std::string m_name;
-  std::string m_type_name;
+  std::string m_node_type_name;
   AnimNode* m_anim_node = nullptr;
   NodeDescriptorBase* m_socket_accessor = nullptr;
   float m_position[2] = {0.f, 0.f};
 };
 
-static inline AnimNodeResource AnimNodeResourceFactory(
-    const std::string& node_type_name) {
-  AnimNodeResource result;
-  result.m_type_name = node_type_name;
-  result.m_anim_node = AnimNodeFactory(node_type_name);
-  result.m_socket_accessor =
-      AnimNodeDescriptorFactory(node_type_name, result.m_anim_node);
-  return result;
-}
+static inline AnimNodeResource* AnimNodeResourceFactory(
+    const std::string& node_type_name);
 
-//
-// AnimGraphResource
-//
-struct AnimGraphConnectionResource {
-  size_t source_node_index = -1;
+struct BlendTreeConnectionResource {
+  int source_node_index = -1;
   std::string source_socket_name;
-  size_t target_node_index = -1;
+  int target_node_index = -1;
   std::string target_socket_name;
+
+  bool operator==(const BlendTreeConnectionResource& other) const {
+    return (
+        source_node_index == other.source_node_index
+        && target_node_index == other.target_node_index
+        && source_socket_name == other.source_socket_name
+
+        && target_socket_name == other.target_socket_name);
+  }
 };
 
-struct AnimGraphResource {
-  std::string m_name;
-  std::vector<AnimNodeResource> m_nodes;
-  std::vector<AnimGraphConnectionResource> m_connections;
+struct BlendTreeResource {
+  std::vector<std::vector<size_t> > m_node_input_connection_indices;
+  std::vector<std::vector<size_t> > m_node_inputs_subtree;
 
-  ~AnimGraphResource() {
-    for (auto & m_node : m_nodes) {
-      delete m_node.m_anim_node;
-      delete m_node.m_socket_accessor;
-    }
+  ~BlendTreeResource() { CleanupNodes(); }
+
+  void Reset() {
+    CleanupNodes();
+
+    m_connections.clear();
+
+    m_node_input_connection_indices.clear();
+    m_node_inputs_subtree.clear();
   }
 
-  AnimGraphResource() { clear(); }
+  void CleanupNodes() {
+    for (AnimNodeResource* node_resource : m_nodes) {
+      delete node_resource->m_anim_node;
+      delete node_resource->m_socket_accessor;
+      delete node_resource;
+    }
 
-  void clear();
-  void clearNodes();
-  void initGraphConnectors();
-  bool saveToFile(const char* filename) const;
-  bool loadFromFile(const char* filename);
+    m_nodes.clear();
+  }
 
-  AnimNodeResource& getGraphOutputNode() { return m_nodes[0]; }
-  AnimNodeResource& getGraphInputNode() { return m_nodes[1]; }
+  void InitGraphConnectors() {
+    AddNode(AnimNodeResourceFactory("BlendTreeSockets"));
+    AnimNodeResource* output_node = GetGraphOutputNode();
+    output_node->m_name = "Outputs";
 
-  size_t getNodeIndex(const AnimNodeResource& node_resource) const {
+    AddNode(AnimNodeResourceFactory("BlendTreeSockets"));
+    AnimNodeResource* input_node = GetGraphInputNode();
+    output_node->m_name = "Inputs";
+  }
+
+  [[nodiscard]] AnimNodeResource* GetGraphOutputNode() const {
+    return m_nodes[0];
+  }
+  [[nodiscard]] AnimNodeResource* GetGraphInputNode() const {
+    return m_nodes[1];
+  }
+
+  int GetNodeIndex(const AnimNodeResource* node_resource) const {
     for (size_t i = 0, n = m_nodes.size(); i < n; i++) {
-      if (&m_nodes[i] == &node_resource) {
+      if (m_nodes[i] == node_resource) {
         return i;
       }
     }
 
+    std::cerr << "Error: could not find node index for node resource "
+              << node_resource << std::endl;
     return -1;
   }
 
-  size_t addNode(const AnimNodeResource &node_resource) {
+  [[maybe_unused]] size_t AddNode(AnimNodeResource* node_resource) {
     m_nodes.push_back(node_resource);
+    m_node_input_connection_indices.emplace_back();
+    m_node_inputs_subtree.emplace_back();
     return m_nodes.size() - 1;
   }
 
-  bool connectSockets(
-      const AnimNodeResource& source_node,
+  [[nodiscard]] size_t GetNumNodes() const { return m_nodes.size(); }
+  [[nodiscard]] AnimNodeResource* GetNode(size_t i) { return m_nodes[i]; }
+  [[nodiscard]] const AnimNodeResource* GetNode(size_t i) const {
+    return m_nodes[i];
+  }
+  [[nodiscard]] const std::vector<AnimNodeResource*>& GetNodes() const {
+    return m_nodes;
+  }
+
+  [[nodiscard]] size_t GetNumConnections() const {
+    return m_connections.size();
+  }
+
+  [[nodiscard]] BlendTreeConnectionResource* GetConnection(size_t i) {
+    return &m_connections[i];
+  }
+
+  [[nodiscard]] const BlendTreeConnectionResource* GetConnection(
+      size_t i) const {
+    return &m_connections[i];
+  }
+
+  [[nodiscard]] const std::vector<BlendTreeConnectionResource>& GetConnections()
+      const {
+    return m_connections;
+  }
+
+  Socket* GetNodeOutputSocket(
+      const AnimNodeResource* node,
+      const std::string& output_socket_name) const;
+
+  const Socket* GetNodeOutputSocketByIndex(
+      const AnimNodeResource* node,
+      const size_t socket_output_index) const;
+
+  Socket* GetNodeInputSocket(
+      const AnimNodeResource* node,
+      const std::string& input_socket_name) const;
+
+  const Socket* GetNodeInputSocketByIndex(
+      const AnimNodeResource* node,
+      const size_t socket_input_index) const;
+
+  std::vector<Socket> GetNodeOutputSockets(const AnimNodeResource* node) const;
+  std::vector<Socket> GetNodeInputSockets(const AnimNodeResource* node) const;
+
+  bool ConnectSockets(
+      const AnimNodeResource* source_node,
       const std::string& source_socket_name,
-      const AnimNodeResource& target_node,
-      const std::string& target_socket_name) {
-    size_t source_node_index = getNodeIndex(source_node);
-    size_t target_node_index = getNodeIndex(target_node);
+      const AnimNodeResource* target_node,
+      const std::string& target_socket_name);
 
-    if (source_node_index >= m_nodes.size()
-        || target_node_index >= m_nodes.size()) {
-      std::cerr << "Cannot connect nodes: could not find nodes." << std::endl;
+  bool DisconnectSockets(
+      const AnimNodeResource* source_node,
+      const std::string& source_socket_name,
+      const AnimNodeResource* target_node,
+      const std::string& target_socket_name);
+
+  bool IsConnectionValid(
+      const AnimNodeResource* source_node,
+      const std::string& source_socket_name,
+      const AnimNodeResource* target_node,
+      const std::string& target_socket_name) const;
+
+  const BlendTreeConnectionResource* FindConnectionForSocket(
+      const AnimNodeResource* node,
+      const std::string& socket_name) const;
+
+  bool IsSocketConnected(
+      const AnimNodeResource* node,
+      const std::string& socket_name) const {
+    const BlendTreeConnectionResource* connection =
+        FindConnectionForSocket(node, socket_name);
+    return connection != nullptr;
+  }
+
+  std::vector<Socket*> GetConstantNodeInputs(
+      std::vector<NodeDescriptorBase*>& instance_node_descriptors) const {
+    std::vector<Socket*> result;
+
+    for (size_t i = 0; i < m_nodes.size(); i++) {
+      for (size_t j = 0,
+                  num_inputs = instance_node_descriptors[i]->m_inputs.size();
+           j < num_inputs;
+           j++) {
+        Socket& input = instance_node_descriptors[i]->m_inputs[j];
+
+        if (*input.m_reference.ptr_ptr == nullptr) {
+          memcpy(
+              &input.m_value,
+              &m_nodes[i]->m_socket_accessor->m_inputs[j].m_value,
+              sizeof(Socket::SocketValue));
+          result.push_back(&input);
+        }
+      }
+    }
+
+    return result;
+  }
+
+  size_t GetNodeIndexForOutputSocket(const std::string& socket_name) const {
+    for (size_t i = 0; i < m_connections.size(); i++) {
+      const BlendTreeConnectionResource& connection = m_connections[i];
+      if (connection.target_node_index == 0
+          && connection.target_socket_name == socket_name) {
+        return connection.source_node_index;
+      }
+    }
+
+    std::cerr << "Error: could not find a node connected to output '"
+              << socket_name << "'." << std::endl;
+
+    return -1;
+  }
+
+  size_t GetNodeIndexForInputSocket(const std::string& socket_name) const {
+    for (size_t i = 0; i < m_connections.size(); i++) {
+      const BlendTreeConnectionResource& connection = m_connections[i];
+      if (connection.source_node_index == 1
+          && connection.source_socket_name == socket_name) {
+        return connection.target_node_index;
+      }
+    }
+
+    std::cerr << "Error: could not find a node connected to input '"
+              << socket_name << "'." << std::endl;
+
+    return -1;
+  }
+
+  void UpdateTreeTopologyInfo();
+
+  [[nodiscard]] const std::vector<size_t>& GetNodeEvalOrder() const {
+    return m_node_eval_order;
+  }
+
+ private:
+  void UpdateNodeEvalOrder() {
+    m_node_eval_order.clear();
+    UpdateNodeEvalOrderRecursive(0);
+  }
+  void UpdateNodeEvalOrderRecursive(size_t node_index);
+  void UpdateNodeSubtrees();
+
+  std::vector<AnimNodeResource*> m_nodes;
+  std::vector<BlendTreeConnectionResource> m_connections;
+  std::vector<size_t> m_node_eval_order;
+};
+
+struct StateMachineTransitionResources {
+  size_t source_state_index = -1;
+  size_t target_state_index = -1;
+  float blend_time = 0.f;
+  bool sync_blend = false;
+};
+
+struct StateMachineResource {
+  std::vector<AnimNodeResource> m_states;
+  std::vector<StateMachineTransitionResources> m_transitions;
+};
+
+struct AnimGraphResource : AnimNodeResource {
+  std::string m_graph_type_name;
+
+  BlendTreeResource m_blend_tree_resource;
+  typedef std::pair<const AnimNodeResource*, std::string> NodeSocketPair;
+  typedef std::map<NodeSocketPair, int> NodeSocketDataOffsetMap;
+
+  StateMachineResource m_state_machine_resource;
+
+  void Clear() { m_blend_tree_resource.Reset(); }
+  bool SaveToFile(const char* filename) const;
+  bool LoadFromFile(const char* filename);
+
+  void CreateBlendTreeInstance(AnimGraphBlendTree& result) const;
+
+  template <typename T>
+  bool RegisterBlendTreeInputSocket(const std::string& socket_name) {
+    Socket socket;
+    socket.m_name = socket_name;
+    socket.m_type = GetSocketType<T>();
+    socket.m_type_size = sizeof(T);
+
+    return RegisterBlendTreeInputSocket(socket);
+  }
+
+  bool RegisterBlendTreeInputSocket(const Socket& socket) {
+    AnimNodeResource* input_node = m_blend_tree_resource.GetGraphInputNode();
+
+    std::vector<Socket> input_sockets =
+        input_node->m_socket_accessor->m_outputs;
+    std::vector<Socket>::const_iterator iter = std::find_if(
+        input_sockets.begin(),
+        input_sockets.end(),
+        [&socket](const Socket& input_socket) {
+          return socket.m_name == input_socket.m_name;
+        });
+
+    if (iter != input_sockets.end()) {
+      std::cerr << "Error: cannot register input socket as socket with name '"
+                << socket.m_name << "' already exists!" << std::endl;
       return false;
     }
 
-    Socket* source_socket =
-        source_node.m_socket_accessor->GetOutputSocket(source_socket_name.c_str());
-    Socket* target_socket =
-        target_node.m_socket_accessor->GetInputSocket(target_socket_name.c_str());
-
-    if (source_socket == nullptr || target_socket == nullptr) {
-      std::cerr << "Cannot connect nodes: could not find sockets." << std::endl;
-      return false;
-    }
-
-    AnimGraphConnectionResource connection;
-    connection.source_node_index = source_node_index;
-    connection.source_socket_name = source_socket_name;
-    connection.target_node_index = target_node_index;
-    connection.target_socket_name = target_socket_name;
-    m_connections.push_back(connection);
+    input_node->m_socket_accessor->m_outputs.push_back(socket);
+    m_socket_accessor->m_inputs = input_node->m_socket_accessor->m_outputs;
 
     return true;
   }
 
-  bool isSocketConnected(
-      const AnimNodeResource& node,
-      const std::string& socket_name) {
-    size_t node_index = getNodeIndex(node);
-    for (const auto & connection : m_connections) {
-      if ((connection.source_node_index == node_index
-           && connection.source_socket_name == socket_name)
-          || ((connection.target_node_index == node_index)
-              && connection.target_socket_name == socket_name)) {
-        return true;
-      }
-    }
+  template <typename T>
+  bool RegisterBlendTreeOutputSocket(const std::string& socket_name) {
+    Socket socket;
+    socket.m_name = socket_name;
+    socket.m_type = GetSocketType<T>();
+    socket.m_type_size = sizeof(T);
 
-    return false;
+    return RegisterBlendTreeOutputSocket(socket);
   }
 
-  void createInstance(AnimGraph& result) const;
+  bool RegisterBlendTreeOutputSocket(const Socket& socket) {
+    AnimNodeResource* output_node = m_blend_tree_resource.GetGraphOutputNode();
 
-  void createRuntimeNodeInstances(AnimGraph& instance) const;
-  void prepareGraphIOData(AnimGraph& instance) const;
-  void setRuntimeNodeProperties(AnimGraph& instance) const;
-  std::vector<Socket*> getConstNodeInputs(std::vector<NodeDescriptorBase*>& instance_node_descriptors) const;
+    std::vector<Socket> output_sockets =
+        output_node->m_socket_accessor->m_inputs;
+    std::vector<Socket>::const_iterator iter = std::find_if(
+        output_sockets.begin(),
+        output_sockets.end(),
+        [&socket](const Socket& input_socket) {
+          return socket.m_name == input_socket.m_name;
+        });
+
+    if (iter != output_sockets.end()) {
+      return false;
+    }
+
+    output_node->m_socket_accessor->m_inputs.push_back(socket);
+    m_socket_accessor->m_outputs = output_node->m_socket_accessor->m_inputs;
+
+    return true;
+  }
+
+  void CreateStateMachineInstance(AnimGraphStateMachine& result) const;
+
+ private:
+  // BlendTree
+  bool SaveBlendTreeResourceToFile(const char* filename) const;
+  void CreateBlendTreeRuntimeNodeInstances(AnimGraphBlendTree& result) const;
+  void PrepareBlendTreeIOData(
+      AnimGraphBlendTree& instance,
+      NodeSocketDataOffsetMap& node_offset_map) const;
+  void CreateBlendTreeConnectionInstances(
+      AnimGraphBlendTree& instance,
+      NodeSocketDataOffsetMap& node_offset_map) const;
+  void SetRuntimeNodeProperties(AnimGraphBlendTree& result) const;
+
+  bool SaveStateMachineResourceToFile(const char* filename) const;
+  bool LoadStateMachineResourceFromJson(nlohmann::json const& json_data);
 };
 
+static inline AnimNodeResource* AnimNodeResourceFactory(
+    const std::string& node_type_name) {
+  AnimNodeResource* result;
+
+  if (node_type_name == "BlendTree") {
+    AnimGraphResource* blend_tree_resource = new AnimGraphResource();
+    blend_tree_resource->m_blend_tree_resource.InitGraphConnectors();
+    result = blend_tree_resource;
+  } else {
+    result = new AnimNodeResource();
+  }
+
+  result->m_node_type_name = node_type_name;
+
+  if (node_type_name == "BlendTreeSockets") {
+    result->m_anim_node = AnimNodeFactory("BlendTree");
+    result->m_socket_accessor = new NodeDescriptorBase();
+  } else {
+    result->m_anim_node = AnimNodeFactory(node_type_name);
+    result->m_socket_accessor =
+        AnimNodeDescriptorFactory(node_type_name, result->m_anim_node);
+  }
+
+  return result;
+}
+
 #endif  //ANIMTESTBED_ANIMGRAPHRESOURCE_H

src/AnimGraph/AnimGraphStateMachine.cc

@@ -0,0 +1,28 @@
+//
+// Created by martin on 17.03.24.
+//
+
+#include "AnimGraphStateMachine.h"
+
+bool AnimGraphStateMachine::Init(AnimGraphContext& context) {
+  assert(false && !"Not yet implemented!");
+  return false;
+}
+
+void AnimGraphStateMachine::MarkActiveInputs(
+    const std::vector<AnimGraphConnection>& input_connections) {
+  assert(false && !"Not yet implemented!");
+}
+
+void AnimGraphStateMachine::CalcSyncTrack(
+    const std::vector<AnimGraphConnection>& input_connections) {
+  assert(false && !"Not yet implemented!");
+}
+
+void AnimGraphStateMachine::UpdateTime(float time_last, float time_now) {
+  assert(false && !"Not yet implemented!");
+}
+
+void AnimGraphStateMachine::Evaluate(AnimGraphContext& context) {
+  assert(false && !"Not yet implemented!");
+}

src/AnimGraph/AnimGraphStateMachine.h

@@ -0,0 +1,35 @@
+//
+// Created by martin on 17.03.24.
+//
+
+#ifndef ANIMTESTBED_ANIMGRAPHSTATEMACHINE_H
+#define ANIMTESTBED_ANIMGRAPHSTATEMACHINE_H
+
+#include "AnimGraphNodes.h"
+
+struct Transition {
+  AnimNode* m_source_state = nullptr;
+  AnimNode* m_target_state = nullptr;
+
+  float m_blend_time = 0.f;
+  bool m_sync_blend = false;
+};
+
+struct AnimGraphStateMachine : public AnimNode {
+  std::vector<AnimNode> m_states;
+  std::vector<Transition> m_transitions;
+  std::vector<std::vector<Transition*> > m_state_out_transitions;
+
+  AnimNode* m_next_state = nullptr;
+  AnimNode* m_current_state = nullptr;
+  Transition* m_active_transition = nullptr;
+
+  bool Init(AnimGraphContext& context);
+  void MarkActiveInputs(const std::vector<AnimGraphConnection>& input_connections) override;
+  void CalcSyncTrack(const std::vector<AnimGraphConnection>& input_connections) override;
+  void UpdateTime(float time_last, float time_now) override;
+  void Evaluate(AnimGraphContext& context) override;
+};
+
+
+#endif  //ANIMTESTBED_ANIMGRAPHSTATEMACHINE_H

src/AnimGraph/AnimNode.cc

@@ -0,0 +1,5 @@
+//
+// Created by martin on 17.03.24.
+//
+
+#include "AnimNode.h"

src/AnimGraph/AnimNode.h

@@ -0,0 +1,76 @@
+//
+// Created by martin on 17.03.24.
+//
+
+#ifndef ANIMTESTBED_ANIMNODE_H
+#define ANIMTESTBED_ANIMNODE_H
+
+#include <string>
+#include <vector>
+
+#include "AnimGraphData.h"
+#include "SyncTrack.h"
+
+struct AnimNode;
+
+enum class AnimNodeEvalState {
+  Undefined,
+  Deactivated,
+  Activated,
+  SyncTrackUpdated,
+  TimeUpdated,
+  Evaluated
+};
+
+struct AnimNode {
+  std::string m_name;
+  std::string m_node_type_name;
+  int m_tick_number = 0;
+  AnimNodeEvalState m_state = AnimNodeEvalState::Undefined;
+
+  float m_time_now = 0.f;
+  float m_time_last = 0.f;
+  SyncTrack m_sync_track;
+
+  virtual ~AnimNode() = default;
+
+  virtual bool Init(AnimGraphContext& context) {
+    m_time_now = 0.f;
+    m_time_last = 0.f;
+    return true;
+  };
+
+  virtual void MarkActiveInputs(
+      const std::vector<AnimGraphConnection>& input_connections) {
+    for (const auto& input : input_connections) {
+      AnimNode* input_node = input.m_source_node;
+      if (input_node != nullptr) {
+        input_node->m_tick_number = m_tick_number;
+        input_node->m_state = AnimNodeEvalState::Activated;
+      }
+    }
+  }
+
+  virtual void CalcSyncTrack(
+      const std::vector<AnimGraphConnection>& input_connections) {
+    for (const auto& input : input_connections) {
+      AnimNode* input_node = input.m_source_node;
+      if (input_node != nullptr
+          && input.m_socket.m_type == SocketType::SocketTypeAnimation
+          && input_node->m_state != AnimNodeEvalState::Deactivated) {
+        m_sync_track = input_node->m_sync_track;
+        return;
+      }
+    }
+  }
+
+  virtual void UpdateTime(float time_last, float time_now) {
+    m_time_last = time_last;
+    m_time_now = time_now;
+    m_state = AnimNodeEvalState::TimeUpdated;
+  }
+
+  virtual void Evaluate(AnimGraphContext& context){};
+};
+
+#endif  //ANIMTESTBED_ANIMNODE_H

src/main.cc

@@ -16,13 +16,17 @@
 #define GLFW_INCLUDE_NONE
 #include <iostream>
 
+#include "3rdparty/imgui-node-editor/imgui_node_editor.h"
 #include "3rdparty/json/json.hpp"
+#include "AnimGraph/AnimGraphBlendTree.h"
+#include "AnimGraph/AnimGraphData.h"
 #include "Camera.h"
 #include "GLFW/glfw3.h"
 #include "SkinnedMesh.h"
+#include "SkinnedMeshRenderer.h"
 #include "SkinnedMeshResource.h"
+#include "embedded_fonts.h"
 #include "src/AnimGraph/AnimGraphEditor.h"
-#include "3rdparty/imgui-node-editor/imgui_node_editor.h"
 
 const int Width = 1024;
 const int Height = 768;
@@ -49,7 +53,6 @@ static void draw_imgui(ImDrawData*);
 #include <cmath>  // fmodf
 #include <fstream>
 
-#include "SkinnedMeshRenderer.h"
 #include "ozz/animation/runtime/animation.h"
 #include "ozz/animation/runtime/sampling_job.h"
 #include "ozz/animation/runtime/skeleton.h"
@@ -156,14 +159,10 @@ struct Viewport {
     this->pass = sg_make_pass(&offscreen_pass_desc);
 
     sg_pipeline_desc gl_pipeline_desc = {
-        .depth = {
-            .compare = SG_COMPAREFUNC_LESS_EQUAL,
-            .write_enabled = true
-        },
+        .depth = {.compare = SG_COMPAREFUNC_LESS_EQUAL, .write_enabled = true},
         .cull_mode = SG_CULLMODE_BACK,
-        .sample_count = cMSAASampleCount
-    };
-//    this->pip = sg_make_pipeline(gl_pipeline_desc);
+        .sample_count = cMSAASampleCount};
+    //    this->pip = sg_make_pipeline(gl_pipeline_desc);
   }
 };
 
@@ -171,13 +170,6 @@ struct ApplicationConfig {
   int window_position[2] = {100, 30};
   int window_size[2] = {1000, 600};
 
-  struct LegacyGraphEditor {
-    bool visible = false;
-    int position[2] = {20, 20};
-    int size[2] = {800, 500};
-  };
-  LegacyGraphEditor legacy_graph_editor;
-
   struct GraphEditor {
     bool visible = false;
     int position[2] = {20, 20};
@@ -186,7 +178,7 @@ struct ApplicationConfig {
     ax::NodeEditor::EditorContext* context = nullptr;
   };
   GraphEditor graph_editor;
-  
+
   struct SkinnedMeshWidget {
     bool visible = false;
     int position[2] = {20, 20};
@@ -223,18 +215,12 @@ void to_json(nlohmann::json& j, const ApplicationConfig& config) {
   j["main_window"]["size"][0] = config.window_size[0];
   j["main_window"]["size"][1] = config.window_size[1];
 
-  j["legacy_graph_editor"]["visible"] = config.legacy_graph_editor.visible;
-  j["legacy_graph_editor"]["position"][0] = config.legacy_graph_editor.position[0];
-  j["legacy_graph_editor"]["position"][1] = config.legacy_graph_editor.position[1];
-  j["legacy_graph_editor"]["size"][0] = config.legacy_graph_editor.size[0];
-  j["legacy_graph_editor"]["size"][1] = config.legacy_graph_editor.size[1];
-
   j["graph_editor"]["visible"] = config.graph_editor.visible;
   j["graph_editor"]["position"][0] = config.graph_editor.position[0];
   j["graph_editor"]["position"][1] = config.graph_editor.position[1];
   j["graph_editor"]["size"][0] = config.graph_editor.size[0];
   j["graph_editor"]["size"][1] = config.graph_editor.size[1];
-  
+
   j["skinned_mesh_widget"]["visible"] = config.skinned_mesh_widget.visible;
   j["skinned_mesh_widget"]["position"][0] =
       config.skinned_mesh_widget.position[0];
@@ -280,29 +266,11 @@ void from_json(const nlohmann::json& j, ApplicationConfig& config) {
     }
   }
 
-  if (j.contains("legacy_graph_editor")) {
-    if (j["legacy_graph_editor"].contains("visible")) {
-      config.legacy_graph_editor.visible = j["legacy_graph_editor"]["visible"];
-    }
-
-    if (j["legacy_graph_editor"].contains("position")
-        and j["legacy_graph_editor"]["position"].size() == 2) {
-      config.legacy_graph_editor.position[0] = j["legacy_graph_editor"]["position"].at(0);
-      config.legacy_graph_editor.position[1] = j["legacy_graph_editor"]["position"].at(1);
-    }
-
-    if (j["legacy_graph_editor"].contains("size")
-        and j["legacy_graph_editor"]["size"].size() == 2) {
-      config.legacy_graph_editor.size[0] = j["legacy_graph_editor"]["size"].at(0);
-      config.legacy_graph_editor.size[1] = j["legacy_graph_editor"]["size"].at(1);
-    }
-  }
-
   if (j.contains("graph_editor")) {
     if (j["graph_editor"].contains("visible")) {
       config.graph_editor.visible = j["graph_editor"]["visible"];
     }
-    
+
     if (j["graph_editor"].contains("position")
         and j["graph_editor"]["position"].size() == 2) {
       config.graph_editor.position[0] = j["graph_editor"]["position"].at(0);
@@ -315,7 +283,7 @@ void from_json(const nlohmann::json& j, ApplicationConfig& config) {
       config.graph_editor.size[1] = j["graph_editor"]["size"].at(1);
     }
   }
-  
+
   if (j.contains("skinned_mesh_widget")) {
     if (j["skinned_mesh_widget"].contains("visible")) {
       config.skinned_mesh_widget.visible = j["skinned_mesh_widget"]["visible"];
@@ -529,7 +497,9 @@ int main() {
 
   // setup sokol_gfx and sokol_time
   stm_setup();
-  sg_desc desc = {.logger = {.func = slog_func}, .context {.sample_count = cMSAASampleCount}};
+  sg_desc desc = {
+      .logger = {.func = slog_func},
+      .context{.sample_count = cMSAASampleCount}};
   sg_setup(&desc);
   assert(sg_isvalid());
 
@@ -550,11 +520,12 @@ int main() {
   skinned_mesh_resource.createInstance(skinned_mesh);
   skinned_mesh.SetCurrentAnimation(0);
 
-  AnimGraph anim_graph;
+  AnimGraphBlendTree anim_graph;
   AnimGraphContext anim_graph_context;
   AnimData anim_graph_output;
   anim_graph_output.m_local_matrices.resize(
       skinned_mesh.m_skeleton.num_soa_joints());
+  AnimGraphEditorClear();
 
   state.time.factor = 1.0f;
 
@@ -566,7 +537,20 @@ int main() {
   ImGuiIO& io = ImGui::GetIO();
   io.ConfigFlags |= ImGuiConfigFlags_DockingEnable;
   io.IniFilename = "ATPImgui.ini";
-  io.Fonts->AddFontDefault();
+
+  //io.Fonts->AddFontDefault();
+  ImFontConfig font_config;
+  font_config.OversampleH = 4;
+  font_config.OversampleV = 4;
+  font_config.GlyphExtraSpacing.x = 1.0f;
+  io.Fonts->AddFontFromMemoryCompressedTTF(
+      //      roboto_medium_ttf_compressed_data,
+      //      roboto_medium_ttf_compressed_size,
+      droid_sans_ttf_compressed_data,
+      droid_sans_ttf_compressed_size,
+      14,
+      &font_config);
+
   io.KeyMap[ImGuiKey_Tab] = GLFW_KEY_TAB;
   io.KeyMap[ImGuiKey_LeftArrow] = GLFW_KEY_LEFT;
   io.KeyMap[ImGuiKey_RightArrow] = GLFW_KEY_RIGHT;
@@ -673,7 +657,8 @@ int main() {
   // Graph Editor
   gApplicationConfig.graph_editor.config.SettingsFile = "graph_editor.json";
   gApplicationConfig.graph_editor.config.NavigateButtonIndex = 2;
-  gApplicationConfig.graph_editor.context = ax::NodeEditor::CreateEditor(&gApplicationConfig.graph_editor.config);
+  gApplicationConfig.graph_editor.context =
+      ax::NodeEditor::CreateEditor(&gApplicationConfig.graph_editor.config);
 
   // draw loop
   while (!glfwWindowShouldClose(w)) {
@@ -795,9 +780,6 @@ int main() {
             &gApplicationConfig.animation_player_widget.visible);
 
         ImGui::Separator();
-        ImGui::Checkbox(
-            "Legacy Graph Editor",
-            &gApplicationConfig.legacy_graph_editor.visible);
 
         ImGui::Checkbox(
             "ImGui Demo",
@@ -811,12 +793,12 @@ int main() {
 
         AnimGraphEditorGetRuntimeGraph(anim_graph);
         anim_graph_context.m_skeleton = &skinned_mesh.m_skeleton;
-        anim_graph.init(anim_graph_context);
+        anim_graph.Init(anim_graph_context);
 
         // For simplicity use first animation data output
         const std::vector<Socket>& graph_output_sockets =
-            anim_graph.getGraphOutputs();
-        for (const auto & output : graph_output_sockets) {
+            anim_graph.GetGraphOutputs();
+        for (const auto& output : graph_output_sockets) {
           if (output.m_type == SocketType::SocketTypeAnimation) {
             anim_graph.SetOutput(output.m_name.c_str(), &anim_graph_output);
           }
@@ -845,7 +827,8 @@ int main() {
 
         ImGui::Begin("Viewport", &gApplicationConfig.viewport_widget.visible);
 
-        if (ImGui::IsWindowHovered() && ImGui::IsMouseDown(ImGuiMouseButton_Right)) {
+        if (ImGui::IsWindowHovered()
+            && ImGui::IsMouseDown(ImGuiMouseButton_Right)) {
           if (gControlMode == ControlMode::ControlModeNone) {
             gControlMode = ControlMode::ControlModeFPS;
             Camera_CalcFromMatrix(&state.camera, &state.camera.mtxView[0]);
@@ -854,8 +837,10 @@ int main() {
         }
 
         ImVec2 viewport_widget_size = ImGui::GetWindowSize();
-        gApplicationConfig.viewport_widget.size[0] = static_cast<int>(viewport_widget_size.x);
-        gApplicationConfig.viewport_widget.size[1] = static_cast<int>(viewport_widget_size.y);
+        gApplicationConfig.viewport_widget.size[0] =
+            static_cast<int>(viewport_widget_size.x);
+        gApplicationConfig.viewport_widget.size[1] =
+            static_cast<int>(viewport_widget_size.y);
 
         ImGui::Text(
             "Viewport size: %d, %d",
@@ -869,12 +854,16 @@ int main() {
         if (static_cast<float>(current_size[0]) != content_size[0]
             || static_cast<float>(current_size[1]) != content_size[1]
             || offscreen_viewport.pass.id == 0) {
-          offscreen_viewport.Resize(static_cast<int>(content_size[0]), static_cast<int>(content_size[1]));
+          offscreen_viewport.Resize(
+              static_cast<int>(content_size[0]),
+              static_cast<int>(content_size[1]));
         }
 
         ImGui::Image(
             (ImTextureID)(uintptr_t)offscreen_viewport.color_image.id,
-            ImVec2(static_cast<float>(offscreen_viewport.size[0]), static_cast<float>(offscreen_viewport.size[1])),
+            ImVec2(
+                static_cast<float>(offscreen_viewport.size[0]),
+                static_cast<float>(offscreen_viewport.size[1])),
             ImVec2(0.0f, 1.0f),
             ImVec2(1.0f, 0.0f));
 
@@ -897,13 +886,17 @@ int main() {
       if (gApplicationConfig.skinned_mesh_widget.visible) {
         ImGui::SetNextWindowPos(
             ImVec2(
-                static_cast<float>(gApplicationConfig.skinned_mesh_widget.position[0]),
-                static_cast<float>(gApplicationConfig.skinned_mesh_widget.position[1])),
+                static_cast<float>(
+                    gApplicationConfig.skinned_mesh_widget.position[0]),
+                static_cast<float>(
+                    gApplicationConfig.skinned_mesh_widget.position[1])),
             ImGuiCond_FirstUseEver);
         ImGui::SetNextWindowSize(
             ImVec2(
-                static_cast<float>(gApplicationConfig.skinned_mesh_widget.size[0]),
-                static_cast<float>(gApplicationConfig.skinned_mesh_widget.size[1])),
+                static_cast<float>(
+                    gApplicationConfig.skinned_mesh_widget.size[0]),
+                static_cast<float>(
+                    gApplicationConfig.skinned_mesh_widget.size[1])),
             ImGuiCond_FirstUseEver);
 
         ImGui::Begin(
@@ -930,13 +923,17 @@ int main() {
       if (gApplicationConfig.animation_player_widget.visible) {
         ImGui::SetNextWindowPos(
             ImVec2(
-                static_cast<float>(gApplicationConfig.animation_player_widget.position[0]),
-                static_cast<float>(gApplicationConfig.animation_player_widget.position[1])),
+                static_cast<float>(
+                    gApplicationConfig.animation_player_widget.position[0]),
+                static_cast<float>(
+                    gApplicationConfig.animation_player_widget.position[1])),
             ImGuiCond_FirstUseEver);
         ImGui::SetNextWindowSize(
             ImVec2(
-                static_cast<float>(gApplicationConfig.animation_player_widget.size[0]),
-                static_cast<float>(gApplicationConfig.animation_player_widget.size[1])),
+                static_cast<float>(
+                    gApplicationConfig.animation_player_widget.size[0]),
+                static_cast<float>(
+                    gApplicationConfig.animation_player_widget.size[1])),
             ImGuiCond_FirstUseEver);
 
         ImGui::Begin(
@@ -1015,8 +1012,8 @@ int main() {
 
       if (state.ozz.animation != nullptr) {
         state.ozz.sampling_job.animation = state.ozz.animation;
-        state.ozz.sampling_job.ratio =
-            static_cast<float>(state.time.absolute) / state.ozz.animation->duration();
+        state.ozz.sampling_job.ratio = static_cast<float>(state.time.absolute)
+                                       / state.ozz.animation->duration();
         state.ozz.sampling_job.context = &skinned_mesh.m_sampling_context;
         state.ozz.sampling_job.output =
             ozz::make_span(skinned_mesh.m_local_matrices);
@@ -1031,9 +1028,10 @@ int main() {
 
       if (state.time.use_graph && !anim_graph.m_nodes.empty()
           && state.time.anim_update_time > 0.) {
-        anim_graph.markActiveNodes();
-        anim_graph.updateTime(state.time.anim_update_time);
-        anim_graph.evaluate(anim_graph_context);
+        // TODO: update for new API after embedding refactor
+        // anim_graph.MarkActiveNodes();
+        // anim_graph.UpdateTime()pdateTime(state.time.anim_update_time);
+        // anim_graph.evaluate(anim_graph_context);
         skinned_mesh.m_local_matrices = anim_graph_output.m_local_matrices;
 
         skinned_mesh.CalcModelMatrices();
@@ -1080,37 +1078,6 @@ int main() {
       ImGui::End();
     }
 
-    // Legacy Animation Graph Editor
-    if (gApplicationConfig.legacy_graph_editor.visible) {
-      ImGui::SetNextWindowPos(
-          ImVec2(
-              gApplicationConfig.legacy_graph_editor.position[0],
-              gApplicationConfig.legacy_graph_editor.position[1]),
-          ImGuiCond_FirstUseEver);
-      ImGui::SetNextWindowSize(
-          ImVec2(
-              gApplicationConfig.legacy_graph_editor.size[0],
-              gApplicationConfig.legacy_graph_editor.size[1]),
-          ImGuiCond_FirstUseEver);
-
-      ImGui::Begin(
-          "Legacy Graph Editor",
-          &gApplicationConfig.legacy_graph_editor.visible,
-          ImGuiWindowFlags_MenuBar);
-
-      ImVec2 graph_editor_position = ImGui::GetWindowPos();
-      gApplicationConfig.legacy_graph_editor.position[0] = graph_editor_position.x;
-      gApplicationConfig.legacy_graph_editor.position[1] = graph_editor_position.y;
-
-      ImVec2 graph_editor_size = ImGui::GetWindowSize();
-      gApplicationConfig.legacy_graph_editor.size[0] = graph_editor_size.x;
-      gApplicationConfig.legacy_graph_editor.size[1] = graph_editor_size.y;
-
-      LegacyAnimGraphEditorUpdate();
-
-      ImGui::End();
-    }
-
     // 3. Show the ImGui test window. Most of the sample code is in ImGui::ShowDemoWindow()
     if (gApplicationConfig.show_imgui_demo_window) {
       ImGui::SetNextWindowPos(ImVec2(460, 20), ImGuiCond_FirstUseEver);

tests/AnimGraphEditorTests.cc

@@ -0,0 +1,40 @@
+#include "AnimGraph/AnimGraphEditor.h"
+#include "catch.hpp"
+
+TEST_CASE("Node Socket To InputPin Conversion", "[animGraphEditor]") {
+  int node_index = 321;
+  int socket_index = 221;
+  long socket_id;
+
+  socket_id = NodeIndexAndSocketIndexToInputPinId(node_index, socket_index);
+
+  int node_index_resolved;
+  int socket_index_resolved;
+
+  InputPinIdToNodeIndexAndSocketIndex(
+      socket_id,
+      &node_index_resolved,
+      &socket_index_resolved);
+
+  CHECK(node_index == node_index_resolved);
+  CHECK(socket_index == socket_index_resolved);
+}
+
+TEST_CASE("Node Socket To OutputPin Conversion", "[animGraphEditor]") {
+  int node_index = 321;
+  int socket_index = 221;
+  long socket_id;
+
+  socket_id = NodeIndexAndSocketIndexToOutputPinId(node_index, socket_index);
+
+  int node_index_resolved;
+  int socket_index_resolved;
+
+  OutputPinIdToNodeIndexAndSocketIndex(
+      socket_id,
+      &node_index_resolved,
+      &socket_index_resolved);
+
+  CHECK(node_index == node_index_resolved);
+  CHECK(socket_index == socket_index_resolved);
+}

tests/AnimGraphEvalTests.cc

@@ -3,8 +3,8 @@
 //
 
 #include "AnimGraph/AnimGraph.h"
+#include "AnimGraph/AnimGraphBlendTreeResource.h"
 #include "AnimGraph/AnimGraphEditor.h"
-#include "AnimGraph/AnimGraphResource.h"
 #include "catch.hpp"
 #include "ozz/animation/offline/animation_builder.h"
 #include "ozz/animation/offline/raw_animation.h"
@@ -141,7 +141,7 @@ TEST_CASE_METHOD(
     SimpleAnimFixture,
     "AnimGraphSimpleEval",
     "[AnimGraphEvalTests]") {
-  AnimGraphResource graph_resource;
+  AnimGraphBlendTreeResource graph_resource;
 
   // Add nodes
   size_t trans_x_node_index =