Operator Overloading Again :-(

CTile& CTile::operator =(CTile &src_tile) {  // Invoke copy ctor. You will need to write it anyway. :)  CTile result(src_tile);  // Swap the data from the copy into the current object (which is known to exist).  std::swap(result, *this);  return *this;  // At end of function, the copied object has its dtor called, which cleans up  // the data that used to exist in 'this' (since it got swapped into the copy).  // So everything works correctly here as long as the copy ctor and the dtor  // are correct.  // Meanwhile, if the copy ctor throws, the object does not get constructed,  // and you won't reach any code that changes 'this' - thus you are exception-  // safe as long as the copy ctor is. What you gained was separation of the  // logic that could throw (making copies of resources) from the logic that  // can't (assigning the resource copies to members of the current object).}

CTile& CTile::operator =(const CTile &src_tile){	// This function overloads the = operator so we can copy tiles correctly; *this is the left-hand operand(dest)	// and src_tile is the right-hand operand(src)	// If the src tile doesn't have any images, don't bother	if (!src_tile.images[0])		return *this; // return the pointer to the existing object	// Also, check to see if *this is valid        if (!this)                return *this; // return the pointer	int index = 0; // looping variable	// First we have to erase the deep stuff that's already there	for (index=0; index<MAX_TILE_IMAGES; index++)		this->images[index] = NULL;	// Copy the shallow members - no x,y because we want the tiles to keep their location and dimensions. We only 	// want to copy the image and image-related variables	this->anim_count = src_tile.anim_count;	this->anim_speed = src_tile.anim_speed;	this->curr_frame = src_tile.curr_frame;	this->next_frame = src_tile.next_frame;	this->num_frames = src_tile.num_frames;	this->width = src_tile.width;	this->height = src_tile.height;	// Now copy the deep members: the HBITMAPS	// First create 2 hdcs to use for blitting - one for the src tile and one for the dest tile	HDC dest_hdc = CreateCompatibleDC(*windraw.Get_Back_HDC()), // hdc for the dest tile		src_hdc = CreateCompatibleDC(*windraw.Get_Back_HDC());	 // hdc for the src tile	// Check the hdcs	if (!dest_hdc || !src_hdc)	{		DeleteDC(dest_hdc); // Delete the dest hdc		dest_hdc = NULL;	// Set it to NULL just in case				DeleteDC(src_hdc); // Delete the src hdc		src_hdc = NULL;	   // Set it to NULL just in case		return *this; // return the pointer	} // end if	// Create 2 old bmps to hold the old data	HBITMAP src_old_bmp = NULL,			dest_old_bmp = NULL;	// loop through all the images of each tile	for (index=0; index<MAX_TILE_IMAGES; index++)	{		// Create a compatible bitmap for the image		this->images[index] = CreateCompatibleBitmap(*windraw.Get_Back_HDC(), this->width, this->height);		// First select the frame into context and save the old one		src_old_bmp = (HBITMAP)SelectObject(src_hdc, src_tile.images[index]);		dest_old_bmp = (HBITMAP)SelectObject(dest_hdc, this->images[index]);				// Check the src_old_bmp		if (!src_old_bmp || !dest_old_bmp)		{				SelectObject(src_hdc, src_old_bmp); // Select the src old bmp back into context			DeleteObject(src_old_bmp); // Delete the src old bmp			src_old_bmp = NULL;		   // Set it to NULL			SelectObject(dest_hdc, dest_old_bmp); // Select the dest old bmp back into context			DeleteObject(dest_old_bmp); // Delete the dest old bmp			dest_old_bmp = NULL;		// Set it to NULL			this->images[index] = NULL; // Set the image to NULL			DeleteDC(dest_hdc); // Delete the dest hdc			dest_hdc = NULL;	// Set it to NULL just in case						DeleteDC(src_hdc); // Delete the src hdc			src_hdc = NULL;	   // Set it to NULL just in case 			return *this; // return the pointer		} // end if		// Blit the data from the src_hdc to the dest_hdc		BitBlt(dest_hdc, 0, 0, this->width, this->height, src_hdc, 0, 0, SRCCOPY);		// Select the old bmps back into context		SelectObject(src_hdc, src_old_bmp);		SelectObject(dest_hdc, dest_old_bmp);	} // end for	// Make sure the src_old_bmp still exists	if (src_old_bmp)	{		DeleteObject(src_old_bmp); // delete the bmp		src_old_bmp = NULL; // set it to NULL	} // end if	// Make sure the dest_old_bmp still exists	if (dest_old_bmp)	{		DeleteObject(dest_old_bmp); // delete the bmp		dest_old_bmp = NULL; // set it to NULL	} // end if	// Make sure the src_hdc still exists	if (src_hdc)	{		DeleteDC(src_hdc); // delete the hdc		src_hdc = NULL; // set it to NULL	} // end if	// Make sure the dest_hdc still exists	if (dest_hdc)	{		DeleteDC(dest_hdc); // delete the hdc		dest_hdc = NULL; // set it to NULL	} // end if	// return pointer to existing object	return *this;} // end CTile::operator=();

CTile& CTile::operator = (const CTile& rhs){    CTile copy(rhs);    copy.Swap(*this);    return *this;}void CTile::Swap(CTile& other){   // Swap elements of *this and elements of other}