====== C and C++ Signatures ======
//(A question was asked regarding using a C++ method instead of a C function for use in a C callback.)//

I'm going to go off memory here, I'm pretty sure this is correct but
forgive me if it isn't 100%.

>error C2664: 'glutIdleFunc' : cannot convert parameter 1 from 'void (void)' to 'void  (__cdecl *)(void)' \\
>        None of the functions with this name in scope match the target type

> glutIdleFunc(display); \\
> void Assignment_1bv2::display()

Declare your assignment display method in your class as static, or
create C-style callbacks (that can then call your class), like so:

<code cpp>
void cstyledisplay()
{
  myclass.display();
}

glutIdleFunc(cstyledisplay);
</code>

Where myclass is your global instance.

Or a static that calls the global instance...

<code cpp>
class assignment2
{
  public:
   static void cstyledisplay()
   {
     myclass.display();
   }
   void display()
   {
    ...
   }
};
</code>

Where myclass is your global instance.

This is typically how you would implement C and C++ interaction in real world applications, so it's a pretty common practice.

> I'm not sure how to troubleshoot this, since putting everything in one cpp file doesn't give me this error.

I'm willing to bet that this is unrelated; you've gone from C functions to C++ methods. They have different signatures. Even if you were to use a type cast in the function call(don't), it wouldn't work (and would likely crash) because non-static C++ methods still have a "this" pointer on the stack, whereas C functions don't.

 --- //[[tjgrant@tatewake.com|Terence J. Grant]] 08/31/2006 09:58//