nanogui@linuxhacker.org

: To make sure I understand this I will outline what I will do :
: 
:  In `class WindowClass' I add sizeof (class Window*) to 
:  the extra bytes supplied by the user. The user of 
:  `class Window' must use a window class created by 
:  the WindowClass class.
: 
:  When creating a window fill in a CREATESTRUCT and pass in 
:  the first parameter of the CreateWindowEx function.
: 
:  Filter the WM_CREATE and take the object pointer from
:  the CREATESTRUCT and set in the extra bytes.
: 
:  Use the extra bytes to get the object pointer.
: 
: This makes the only change I need the macro I posted earlier plus the
: code to set a long word.

You only need the code to set a long word.  Your
earlier macro gets the length of extra bytes, it's not needed.

Greg