[AD] GFX_SAFE under Windows

["Eric Botcazou" <ebotcazou@xxxxxxxxxx>]

There are two reports (the first on the AL mailing list, the second at
SourceForge) on the failure by Allegro to properly set the GFX_SAFE graphic
mode under Windows. Basically, fullscreen 320x200x8 is not a reliable mode
under DirectX 3 and may even hang Allegro.

I recently posted a patch which should prevent Allegro from simply hanging
in this case, but I'm unsure of that.
I'm wondering if it wouldn't be better to change the way GFX_SAFE behaves
under Windows; as Windows is a windowed OS (!), it would be more consistent
to use the GFX_DIRECTX_WIN windowed driver instead of the fullscreen one;
the windowed driver is now quite complete (asm color conversion from and to
every color depth, MMX optimizations if supported) and, with a slight
modification, will work on every graphic card.

But GFX_SAFE first tries to set a GFX_AUTODETECTed mode, and under Windows
GFX_AUTODETECT means fullscreen.
So either we also change the behaviour of GFX_AUTODETECT under Windows or
we'll have to change the behaviour of GFX_SAFE.

What do you think about that ?

--
Eric Botcazou
ebotcazou@xxxxxxxxxx