Hey,

I'm trying to embed an Allegro display into my application so I can make a scene editor in C# with Windows Forms. There's only one small problem: the callback method used in al_win_add_window_callback or al_win_remove_window_callback doesn't let me return an LRESULT... Which means I can't suppress some events (namely WM_MOUSEACTIVATE).

There is an easy fix, though!

The callback method should be declared as so:

bool (*callback)(ALLEGRO_DISPLAY *, UINT, WPARAM, LPARAM, LRESULT*, void *)

When the callback returns true, return the LRESULT (which hopefully was assigned to by the callback) instead of TRUE as is done here:

   for (i = 0; i < _al_vector_size(&win_display->msg_callbacks); ++i) {
      ALLEGRO_DISPLAY_WIN_CALLBACK *ptr = _al_vector_ref(&win_display->msg_callbacks, i);
      if ((ptr->proc)(d, message, wParam, lParam, ptr->userdata))
         return TRUE;
   }

(This is in the window_callback method defined in wwindow.c; I would give line numbers but my copy of Allegro is out of date right now).

This is necessary for a multitude of WM_* messages. WM_MOUSEACTIVATE, for example, expects a special return value. Right now, MA_ACTIVATE is always returned.

I can submit a patch very soon if this API change is acceptable. I don't know if anyone else other than me uses this method, anyway .

edit: I've attached a patch that should provide the extra functionality. Everything works fine on my end (including ex_menu).