Added breadcrumb navigation for embedded graphs.

src/AnimGraph/AnimGraphEditor.cc

@@ -15,7 +15,10 @@
 
 struct EditorState {
   AnimGraphResource* rootGraphResource = nullptr;
-  AnimGraphResource* currentGraphResource = nullptr;
+
+  std::vector<AnimGraphResource*> hierarchyStack;
+  size_t hierarchyStackIndex = 0;
+
   bool isGraphLoadedThisFrame = false;
 };
 
@@ -259,18 +262,25 @@ void AnimGraphEditorRenderSidebar(
 }
 
 void AnimGraphEditorClear() {
-  sEditorState.currentGraphResource = nullptr;
+  sEditorState.hierarchyStack.clear();
   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.currentGraphResource = sEditorState.rootGraphResource;
+
+  sEditorState.hierarchyStack.push_back(sEditorState.rootGraphResource);
+  sEditorState.hierarchyStack[sEditorState.hierarchyStackIndex] =
+      sEditorState.hierarchyStack.back();
 }
 
 void AnimGraphEditorUpdate(ax::NodeEditor::EditorContext* context) {
   ax::NodeEditor::SetCurrentEditor(context);
 
+  //
+  // Menu bar
+  //
   ImGui::BeginMenuBar();
   if (ImGui::Button("Save")) {
     sEditorState.rootGraphResource->SaveToFile("editor_graph.json");
@@ -289,14 +299,47 @@ void AnimGraphEditorUpdate(ax::NodeEditor::EditorContext* context) {
   memset(graph_name_buffer, 0, sizeof(graph_name_buffer));
   strncpy(
       graph_name_buffer,
-      sEditorState.currentGraphResource->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))) {
-    sEditorState.currentGraphResource->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);
 
   //
@@ -305,13 +348,13 @@ void AnimGraphEditorUpdate(ax::NodeEditor::EditorContext* context) {
   ax::NodeEditor::Begin("Graph Editor");
 
   for (size_t node_id = 0,
-              n = sEditorState.currentGraphResource->m_blend_tree_resource
-                      .GetNumNodes();
+              n = sEditorState.hierarchyStack[sEditorState.hierarchyStackIndex]
+                      ->m_blend_tree_resource.GetNumNodes();
        node_id < n;
        node_id++) {
     AnimNodeResource* node_resource =
-        sEditorState.currentGraphResource->m_blend_tree_resource.GetNode(
-            node_id);
+        sEditorState.hierarchyStack[sEditorState.hierarchyStackIndex]
+            ->m_blend_tree_resource.GetNode(node_id);
 
     if (node_id == 0 || node_id == 1) {
       // continue;
@@ -327,8 +370,8 @@ void AnimGraphEditorUpdate(ax::NodeEditor::EditorContext* context) {
 
     // Inputs
     std::vector<Socket> node_inputs =
-        sEditorState.currentGraphResource->m_blend_tree_resource
-            .GetNodeInputSockets(node_resource);
+        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(
@@ -342,8 +385,8 @@ void AnimGraphEditorUpdate(ax::NodeEditor::EditorContext* context) {
 
     // Outputs
     std::vector<Socket> node_outputs =
-        sEditorState.currentGraphResource->m_blend_tree_resource
-            .GetNodeOutputSockets(node_resource);
+        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(
@@ -364,24 +407,26 @@ void AnimGraphEditorUpdate(ax::NodeEditor::EditorContext* context) {
 
   int link_id = 0;
   for (size_t connection_id = 0,
-              n = sEditorState.currentGraphResource->m_blend_tree_resource
-                      .GetNumConnections();
+              n = sEditorState.hierarchyStack[sEditorState.hierarchyStackIndex]
+                      ->m_blend_tree_resource.GetNumConnections();
        connection_id < n;
        connection_id++) {
     const BlendTreeConnectionResource* connection_resource =
-        sEditorState.currentGraphResource->m_blend_tree_resource.GetConnection(
-            connection_id);
+        sEditorState.hierarchyStack[sEditorState.hierarchyStackIndex]
+            ->m_blend_tree_resource.GetConnection(connection_id);
 
     const AnimNodeResource* source_node_resource =
-        sEditorState.currentGraphResource->m_blend_tree_resource.GetNode(
-            connection_resource->source_node_index);
+        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.currentGraphResource->m_blend_tree_resource.GetNode(
-            connection_resource->target_node_index);
+        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());
@@ -411,8 +456,8 @@ void AnimGraphEditorUpdate(ax::NodeEditor::EditorContext* context) {
               &source_node_socket_index);
 
           const AnimNodeResource* source_node =
-              sEditorState.currentGraphResource->m_blend_tree_resource.GetNode(
-                  source_node_index);
+              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;
@@ -427,21 +472,21 @@ void AnimGraphEditorUpdate(ax::NodeEditor::EditorContext* context) {
               &target_node_socket_index);
 
           const AnimNodeResource* target_node =
-              sEditorState.currentGraphResource->m_blend_tree_resource.GetNode(
-                  target_node_index);
+              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;
           }
 
           const Socket* source_socket =
-              sEditorState.currentGraphResource->m_blend_tree_resource
-                  .GetNodeOutputSocketByIndex(
+              sEditorState.hierarchyStack[sEditorState.hierarchyStackIndex]
+                  ->m_blend_tree_resource.GetNodeOutputSocketByIndex(
                       source_node,
                       source_node_socket_index);
           const Socket* target_socket =
-              sEditorState.currentGraphResource->m_blend_tree_resource
-                  .GetNodeInputSocketByIndex(
+              sEditorState.hierarchyStack[sEditorState.hierarchyStackIndex]
+                  ->m_blend_tree_resource.GetNodeInputSocketByIndex(
                       target_node,
                       target_node_socket_index);
 
@@ -458,8 +503,8 @@ void AnimGraphEditorUpdate(ax::NodeEditor::EditorContext* context) {
                     ->m_inputs[target_node_socket_index]
                     .m_name;
 
-            sEditorState.currentGraphResource->m_blend_tree_resource
-                .ConnectSockets(
+            sEditorState.hierarchyStack[sEditorState.hierarchyStackIndex]
+                ->m_blend_tree_resource.ConnectSockets(
                     source_node,
                     source_socket_name,
                     target_node,
@@ -522,11 +567,12 @@ void AnimGraphEditorUpdate(ax::NodeEditor::EditorContext* context) {
       if (!node_type_name.empty()) {
         AnimNodeResource* node_resource =
             AnimNodeResourceFactory(node_type_name);
-        size_t node_id = sEditorState.currentGraphResource
-                             ->m_blend_tree_resource.GetNumNodes();
+        size_t node_id =
+            sEditorState.hierarchyStack[sEditorState.hierarchyStackIndex]
+                ->m_blend_tree_resource.GetNumNodes();
         ax::NodeEditor::SetNodePosition(node_id, popup_mouse_position);
-        sEditorState.currentGraphResource->m_blend_tree_resource.AddNode(
-            node_resource);
+        sEditorState.hierarchyStack[sEditorState.hierarchyStackIndex]
+            ->m_blend_tree_resource.AddNode(node_resource);
       }
 
       ImGui::EndPopup();
@@ -549,9 +595,10 @@ void AnimGraphEditorUpdate(ax::NodeEditor::EditorContext* context) {
 
     if (selected_node_id.Get() != 0) {
       AnimGraphEditorRenderSidebar(
-          sEditorState.currentGraphResource->m_blend_tree_resource,
-          sEditorState.currentGraphResource->m_blend_tree_resource.GetNode(
-              selected_node_id.Get()));
+          sEditorState.hierarchyStack[sEditorState.hierarchyStackIndex]
+              ->m_blend_tree_resource,
+          sEditorState.hierarchyStack[sEditorState.hierarchyStackIndex]
+              ->m_blend_tree_resource.GetNode(selected_node_id.Get()));
     }
   }
 
@@ -561,11 +608,23 @@ void AnimGraphEditorUpdate(ax::NodeEditor::EditorContext* context) {
       ax::NodeEditor::GetDoubleClickedNode();
   if (!double_clicked_node_id.Invalid) {
     AnimNodeResource* clicked_node_resource =
-        sEditorState.currentGraphResource->m_blend_tree_resource.GetNode(
-            double_clicked_node_id.Get());
+        sEditorState.hierarchyStack[sEditorState.hierarchyStackIndex]
+            ->m_blend_tree_resource.GetNode(double_clicked_node_id.Get());
     if (clicked_node_resource->m_node_type_name == "BlendTree") {
-      sEditorState.currentGraphResource =
+      AnimGraphResource* clicked_graph_resource =
           dynamic_cast<AnimGraphResource*>(clicked_node_resource);
+      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++;
+      }
+
       ax::NodeEditor::ClearSelection();
     }
   }