Closes #141

luth/source/luth/core/App.cpp

@@ -426,6 +426,7 @@ namespace Luth
         m_FrameData.Shutdown();
         IOThread::Shutdown();
         JobSystem::Shutdown();
+        EventBus::FlushAll();
         Memory::TaggedPageAllocator::Get().Shutdown();
         Memory::MemoryTracker::Shutdown();
     }

luth/source/luth/events/EventBus.h

@@ -88,6 +88,18 @@ namespace Luth
             GetBus(bus).ProcessEvents();
         }
 
+        // Drop any queued events and subscribers without dispatching.
+        static void Flush(BusType bus) {
+            GetBus(bus).Flush();
+        }
+
+        // Drop all queued events and subscribers without dispatching.
+        static void FlushAll() {
+            for (size_t i = 0; i < static_cast<size_t>(BusType::COUNT); ++i) {
+                GetBus(static_cast<BusType>(i)).Flush();
+            }
+        }
+
         class BusInstance {
         public:
             template<typename T, typename... Args>
@@ -151,6 +163,20 @@ namespace Luth
                 }
             }
 
+            void Flush() {
+                std::queue<std::pair<EventPtr, EventTypeID>> pending;
+                {
+                    std::lock_guard<std::mutex> lock(m_QueueLock);
+                    pending.swap(m_EventQueue);
+                }
+
+                while (!pending.empty())
+                    pending.pop();
+
+                m_Subscribers.clear();
+                m_NextSubId = 0;
+            }
+
             template<typename T>
             static EventTypeID GetEventTypeID() {
                 static EventTypeID typeID = NextEventTypeID();