Add persistent shared editor tree interactions

editor/src/panels/HierarchyPanel.cpp

@@ -10,6 +10,25 @@
 #include "UI/UI.h"
 #include <imgui.h>
 
+namespace {
+
+void DrawHierarchyTreePrefix(const XCEngine::Editor::UI::TreeNodePrefixContext& context) {
+    if (!context.drawList) {
+        return;
+    }
+
+    const ImVec4 color = XCEngine::Editor::UI::NavigationTreePrefixColor(context.selected, context.hovered);
+    const float size = 9.0f;
+    const float centerX = context.min.x + (context.max.x - context.min.x) * 0.5f;
+    const float centerY = context.min.y + (context.max.y - context.min.y) * 0.5f;
+    const ImVec2 min(centerX - size * 0.5f, centerY - size * 0.5f);
+    const ImVec2 max(centerX + size * 0.5f, centerY + size * 0.5f);
+    context.drawList->AddRect(min, max, ImGui::GetColorU32(color), 1.5f);
+    context.drawList->AddLine(ImVec2(min.x, centerY), ImVec2(max.x, centerY), ImGui::GetColorU32(color), 1.0f);
+}
+
+} // namespace
+
 namespace XCEngine {
 namespace Editor {
 
@@ -122,27 +141,33 @@ void HierarchyPanel::RenderEntity(::XCEngine::Components::GameObject* gameObject
             CommitRename();
         }
     } else {
-        UI::TreeNodeOptions nodeOptions;
-        nodeOptions.selected = m_context->GetSelectionManager().IsSelected(gameObject->GetID());
-        nodeOptions.leaf = gameObject->GetChildCount() == 0;
+        UI::TreeNodeDefinition nodeDefinition;
+        nodeDefinition.options.selected = m_context->GetSelectionManager().IsSelected(gameObject->GetID());
+        nodeDefinition.options.leaf = gameObject->GetChildCount() == 0;
+        const std::string persistenceKey = std::to_string(gameObject->GetUUID());
+        nodeDefinition.persistenceKey = persistenceKey;
+        nodeDefinition.prefix.width = UI::NavigationTreePrefixWidth();
+        nodeDefinition.prefix.draw = DrawHierarchyTreePrefix;
+        nodeDefinition.callbacks.onInteraction = [this, gameObject](const UI::TreeNodeResult& node) {
+            if (node.clicked) {
+                Actions::HandleHierarchySelectionClick(*m_context, gameObject->GetID(), ImGui::GetIO().KeyCtrl);
+            }
+
+            if (node.doubleClicked) {
+                BeginRename(gameObject);
+            }
+        };
+        nodeDefinition.callbacks.onRenderExtras = [this, gameObject]() {
+            Actions::BeginHierarchyEntityDrag(gameObject);
+            Actions::AcceptHierarchyEntityDrop(*m_context, gameObject);
+            Actions::DrawHierarchyEntityContextPopup(*m_context, gameObject);
+        };
 
         const UI::TreeNodeResult node = UI::DrawTreeNode(
+            &m_treeState,
             (void*)gameObject->GetUUID(),
             gameObject->GetName().c_str(),
-            nodeOptions);
-        
-        if (node.clicked) {
-            Actions::HandleHierarchySelectionClick(*m_context, gameObject->GetID(), ImGui::GetIO().KeyCtrl);
-        }
-        
-        if (node.doubleClicked) {
-            BeginRename(gameObject);
-        }
-        
-        Actions::BeginHierarchyEntityDrag(gameObject);
-        Actions::AcceptHierarchyEntityDrop(*m_context, gameObject);
-
-        Actions::DrawHierarchyEntityContextPopup(*m_context, gameObject);
+            nodeDefinition);
         
         if (node.open) {
             for (size_t i = 0; i < gameObject->GetChildCount(); i++) {