Add support for event subscription (delegates)

code/qcommon/delegate.cpp

@@ -0,0 +1,52 @@
+/*
+===========================================================================
+Copyright (C) 2025 the OpenMoHAA team
+
+This file is part of OpenMoHAA source code.
+
+OpenMoHAA source code is free software; you can redistribute it
+and/or modify it under the terms of the GNU General Public License as
+published by the Free Software Foundation; either version 2 of the License,
+or (at your option) any later version.
+
+OpenMoHAA source code is distributed in the hope that it will be
+useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with OpenMoHAA source code; if not, write to the Free Software
+Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+===========================================================================
+*/
+
+#include "delegate.h"
+
+uint64_t DelegateHandle::currentHandle = 0;
+
+DelegateHandle::DelegateHandle()
+    : handle(GenerateDelegateID())
+{}
+
+bool DelegateHandle::operator==(const DelegateHandle& other) const
+{
+    return handle == other.handle;
+}
+
+bool DelegateHandle::operator!=(const DelegateHandle& other) const
+{
+    return handle != other.handle;
+}
+
+uint64_t DelegateHandle::GenerateDelegateID()
+{
+    uint64_t handle;
+
+    handle = ++currentHandle;
+
+    if (handle == 0) {
+        handle = ++currentHandle;
+    }
+
+    return handle;
+}