[AD] win32 screen change problem.

[aj <aj@xxxxxxxxxx>]

winXP
alg 4.1.14
screen driver  GFX_DIRECTX_WINDOWED


i have a situation where the user wishes to change the screen properties 
whilst my allegro application is still running..
the user is adding a second monitor, so the original screen properties W, 
H, Depth  do not change.
the allegro window (still running on the original monitor) goes black..
i have moved the mouse over the window, that would cause a total screen 
redraw, but nothing occurs, nor does it crash.. so i can only presume that 
the ALLEGRO_SCREEN var is  still OK, however nothing is 
visible..  therefore with my limited knowledge of how the directX surface 
scheme works in allegro i can only guess its that the directX surface is 
lost during the screen switch (when user turns on the dual monitor) and not 
able to be re-initialized or  the allegro app has not attempted to 
re-initialize (or re-acquire) a new directX surface, possibly because it is 
unaware of it going missing ? ?

i have checked MSDN for info, and apparently applications receive the 
WM_DISPLAYCHANGE message with the W, H, Depth  packed in the lParam and wParam.
as the W,H,D of the original screen do not change, i am not sure if the app 
would receive the message, (problem 1).

if this is the case,  possible solution would be for  allegro to act on the 
WM_DISPLAYCHANGE message and re-acquire its directX surfaces.

however if the app never receives the WM_DISPLAYCHANGE message, possible 
due to the fact that W,H,D of the original monitor has not changed,  how 
can i force the re-acquiring of the directX surfaces ?


aj.