#5347: Fix a crash in scene::getNodeIndices when a primitive without …

…a parent is encountered.

Protect the calling EntityInspector code against out_of_range exceptions that might be thrown by getNodeIndices.

libs/scene/SelectionIndex.cpp

@@ -115,18 +115,24 @@ std::pair<std::size_t, std::size_t> getNodeIndices(const scene::INodePtr& node)
 	}
 	else if (Node_isPrimitive(node))
 	{
-		scene::INodePtr parent = node->getParent();
+		auto parent = node->getParent();
 
-		// Node is a primitive, find parent entity and child index
-		EntityFindIndexWalker walker(parent);
-		GlobalSceneGraph().root()->traverse(walker);
+		// In rare cases, such as when a drag-selection brush is deleted
+		// but still selected, we might reach this point with a primitive
+		// node without a parent. At least we shouldn't crash.
+		if (parent)
+		{
+			// Node is a primitive, find parent entity and child index
+			EntityFindIndexWalker walker(parent);
+			GlobalSceneGraph().root()->traverse(walker);
 
-		result.first = walker.getIndex(); // might throw
+			result.first = walker.getIndex(); // might throw
 
-		PrimitiveFindIndexWalker brushWalker(node);
-		parent->traverse(brushWalker);
+			PrimitiveFindIndexWalker brushWalker(node);
+			parent->traverse(brushWalker);
 
-		result.second = walker.getIndex(); // might throw
+			result.second = walker.getIndex(); // might throw
+		}
 	}
 	else
 	{

radiant/ui/einspector/EntityInspector.cpp

@@ -1197,9 +1197,17 @@ void EntityInspector::getEntityFromSelectionSystem()
         scene::INodePtr selectedNodeParent = selectedNode->getParent();
         changeSelectedEntity(selectedNodeParent);
 
-        auto indices = scene::getNodeIndices(selectedNode);
+        try
+        {
+            auto indices = scene::getNodeIndices(selectedNode);
 
-        _primitiveNumLabel->SetLabelText(fmt::format(_("Entity {0}, Primitive {1}"), indices.first, indices.second));
+            _primitiveNumLabel->SetLabelText(fmt::format(_("Entity {0}, Primitive {1}"), indices.first, indices.second));
+        }
+        catch (const std::out_of_range& ex)
+        {
+            rWarning() << ex.what() << std::endl;
+            _primitiveNumLabel->SetLabelText("-");
+        }
     }
 }