strange C++ abnomality........

[Josiah Avery <josiahavery@hotmail.com>]

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  Hello,

 

  Hopefully. someone will be able to correct me on this, but I belive that I've run into a rather perculiar limitation in ANSI compilant C++ compilers.

Consider the following example:

 

class CTriangleRenderer

{

   public:

      // blah blah...

      char * RenderVisibleSet(CPolygon**);

      char * MMX_RenderVisibleSet(CPolygon**);

      char *(*CB_RenderSet)(CPolygon**);

     // blah blah, and so forth

   private:

      void SwapRenderers(void);

     // blah blah.

 };

 

Now,humor me for a but a moment longer. Let us suppose that the rendering function used is dependant on the build version version of the project.

If the version of pre-release than 'RenderVisibleSet' is used -- else 'MMX_RenderVisibleSet' is used. In the constructor, assume the following lines are

present:

 

#ifdef __DEBUG_VERSION__

SwapRenderers();

#endif

 

and CTriangleRenderer::SwapRenderers is defined as:

{

#ifdef __DEBUG_VERSION__

 CB_RenderSet = CTriangleSet::RenderVisibleSet;

#else

 CB_RenderSet = CTriangleSet::MMX_RenderVisibleSet;

#endif

}

 

For some reason, this is illegal. You can't assign methods pointers to callbacks which reside within the class in question. I've been messing around with hacks to trying to get

it to work ( mainly casting / tweaking of compiler options ). I hope it is something that I am just overlooking, as that seems a rather... foolish limitation.

 

I hope someone can help;

Thanks in advance,

Josiah.

  

 

 

 

     

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