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** Copyright (C) 2008-2012 NVIDIA Corporation.
** Copyright (C) 2017 The Qt Company Ltd.
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#pragma once
#ifndef QT3DS_RENDER_TAGGED_POINTER_H
#define QT3DS_RENDER_TAGGED_POINTER_H
#include "Qt3DSRender.h"
#include "foundation/StringTable.h"

namespace qt3ds {
namespace render {

    // User's will need to define specialize this struct in order
    // to de-tag a pointer.
    template <typename TDataType>
    struct SPointerTag
    {
        /* Expected API for runtime RTTI
        static CRegisteredString GetTag() { return g_dtype_specific_string; }
        */
    };

    // A pointer tagged with an identifier so we can have generic
    // user data that is still somewhat typesafe.
    struct STaggedPointer
    {
        void *m_UserData;
        QT3DSU32 m_Tag;
        STaggedPointer()
            : m_UserData(NULL)
            , m_Tag(0)
        {
        }

        STaggedPointer(void *inUserData, QT3DSU32 inTag)
            : m_UserData(inUserData)
            , m_Tag(inTag)
        {
        }

        template <typename TDataType>
        STaggedPointer(TDataType *inType)
            : m_UserData(reinterpret_cast<void *>(inType))
            , m_Tag(SPointerTag<TDataType>::GetTag())
        {
        }

        template <typename TDataType>
        TDataType *DynamicCast() const
        {
            if (m_Tag == SPointerTag<TDataType>::GetTag())
                return reinterpret_cast<TDataType *>(m_UserData);
            return NULL;
        }
    };
}
}

#endif