Added original SDK code for Alien Swarm.

public/iserverunknown.h

@@ -0,0 +1,35 @@
+//========= Copyright <20> 1996-2005, Valve Corporation, All rights reserved. ============//
+//
+// Purpose: 
+//
+// $NoKeywords: $
+//=============================================================================//
+
+#ifndef ISERVERUNKNOWN_H
+#define ISERVERUNKNOWN_H
+
+#ifdef _WIN32
+#pragma once
+#endif
+
+
+#include "ihandleentity.h"
+
+class ICollideable;
+class IServerNetworkable;
+class CBaseEntity;
+
+
+// This is the server's version of IUnknown. We may want to use a QueryInterface-like
+// mechanism if this gets big.
+class IServerUnknown : public IHandleEntity
+{
+public:
+	// Gets the interface to the collideable + networkable representation of the entity
+	virtual ICollideable*		GetCollideable() = 0;
+	virtual IServerNetworkable*	GetNetworkable() = 0;
+	virtual CBaseEntity*		GetBaseEntity() = 0;
+};
+
+
+#endif // ISERVERUNKNOWN_H