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    <p>Perhaps you want to do a dynamic_cast&lt;></p> <p>You may want C++ to behave like some language with reflection such as C#. That is not true.<br> This is another post that is similar. </p> <pre><code>http://stackoverflow.com/questions/3049404/apples-oranges-and-pointers-to-the-most-derived-c-class </code></pre> <p>You may be asking something of C++ that it does not have.</p> <pre><code>class basex { public: virtual ~basex() {}; }; class middlex : public basex { public: //middlex() = default; }; int dynamic_test() { basex * cbq = new middlex; basex * cbq2 = new basex; middlex * mcp = dynamic_cast&lt;middlex *&gt;(cbq); //should suceed if (nullptr != mcp) { cout &lt;&lt; "dynamic cast worked" &lt;&lt; endl; } else { cout &lt;&lt; "dynamic cast failed" &lt;&lt; endl; } //should fail middlex * mcp2 = dynamic_cast&lt;middlex *&gt;(cbq2); if (nullptr != mcp2) { cout &lt;&lt; "dynamic cast worked" &lt;&lt; endl; } else { cout &lt;&lt; "dynamic cast failed" &lt;&lt; endl; } return 0; } </code></pre> <p>You seem like you really want to do simple casts and the member function does not seem useful </p> <p>.....................</p> <pre><code>template &lt; class T &gt; T* GetTop() </code></pre> <p>needs improvement It is simply doing a cast .... and casts require the destination type static_cast requires explicit type argument thus.. GetTop requires explicit type argument</p> <p>GetTop is a member function ... the T can be any class ... the code provided .. has no given parameters for type deduction ... the pointer your provide is ... C++ this ...thus you may call it only TopClass or derived objects. (Lets exclude complicated casts)</p> <pre><code>TopClass * top = m-&gt;GetTop(); </code></pre> <p>Compiler will try to make sense of right side .............not considering left side<br> The compiler does not consider the left side for type deduction.. there is no assistance to type deduction .. it will simply try to make sense of the right side<br> I say that because it seems you might believe the compiler will use the type TopClass for type deduction ... it will not </p> <p>This will work compile </p> <pre><code>TopClass * top = m-&gt;GetTop&lt;TopClass&gt;(); </code></pre> <p>But its doing nothing more than an explicit static_cast</p> <p>Maybe you should state what you are intending to do</p>
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    1. POHow to get top class from base class
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    1. COi know, this is working "GetTop<TopClass>();". Let's say, i have lots of derived classes and there is only one top class. Let's say, i want to pass my object to Scene function and it accepts only SceneObject. Class that does not derive SceneObject cannot be passed. MiddleClass is very easy to get because i store references to base class, but i have too many top classes and it just looks horrible to Read class Type and then cast to my right top class. So i thought there is a more clever way how to do that and have code clean and short.
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    2. COand dynamic cast is unfortunately slow. I know what i am casting, i don't need to check it.
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    3. CO@wh1sp3r Does Scene take a SceneObject or SceneObject & or SceneObject *??? Full Object, Reference, Pointer? You might want to include that code sample here. Do you have a container or array of ... SceneObject * .. or TopClass *? If are storing pointers to objects and space permits ... perhaps you can store SceneObjects seperately. Sometime integers are the same size as pointers. Perhaps you can store [Object * x, int desired] where desired is true false. Have you tested dynamic_cast a few times to make sure it is toooooo Sloooooow? Do you have immediate memory contraints.
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