X-Git-Url: http://git.tdb.fi/?a=blobdiff_plain;f=source%2Fgame%2Fhandle.h;h=1808654f5e13ee4b60dd05ad633bab1b4249b75d;hb=b81c61ce06116727ebaef489f174fac6e0be6760;hp=d384f35c3c1fae6f29b1871a4c955079078d3e75;hpb=248d62f7240d342982ade65a510be912b867fe49;p=libs%2Fgame.git

diff --git a/source/game/handle.h b/source/game/handle.h
index d384f35..1808654 100644
--- a/source/game/handle.h
+++ b/source/game/handle.h
@@ -1,6 +1,7 @@
 #ifndef MSP_GAME_HANDLE_H_
 #define MSP_GAME_HANDLE_H_
 
+#include <functional>
 #include <stdexcept>
 #include "pool.h"
 
@@ -23,21 +24,30 @@ protected:
 
 public:
 	Handle() = default;
-
-	static Handle from_object(T *o) { Handle h; h.ptr = o; return h; }
+	Handle(nullptr_t) { }
 
 	template<typename U>
 		requires std::is_base_of_v<T, U>
 	Handle(const Handle<U> &other): ptr(other.ptr) { }
 
+	static Handle from_object(T *o) { Handle h; h.ptr = o; return h; }
+
 	T *get() const { return ptr; }
 	T &operator*() const { return *ptr; }
 	T *operator->() const { return ptr; }
 	explicit operator bool() const { return ptr; }
 
 	bool operator==(const Handle &other) const = default;
+	bool operator<(const Handle &other) const { return std::less<T *const>()(ptr, other.ptr); }
 };
 
+template<typename T, typename U>
+	requires std::is_base_of_v<U, T>
+Handle<T> dynamic_handle_cast(Handle<U> h)
+{
+	return Handle<T>::from_object(dynamic_cast<T *>(h.get()));
+}
+
 } // namespace Msp::Game
 
 #endif