GetKeyboardState problems in Age of Empires II

[Stevie Trujillo]

On Thu, 18 Apr 2013 17:39:33 +0900
Dmitry Timoshkov <dmitry at baikal.ru> wrote:

> [please don't omit wine-devel when replying]
> 
> Stevie Trujillo <stevie.trujillo at gmail.com> wrote:
> 
> > > Stevie Trujillo <stevie.trujillo at gmail.com> wrote:
> > > > Another (minor) problem raised in the bugzilla entry is that,
> > > > if a key is pressed when changing window, and released before
> > > > returning, GetKeyboardState() will claim the key is still
> > > > pressed (0x80). But this is easy to workaround, just hit the
> > > > key again inside the game and it will stop scrolling.
> > > 
> > > dlls/winex11.drv/keyboard.c,X11DRV_KeymapNotify() should take
> > > care of that, if it doesn't - please debug why (probably a bug in
> > > your WM).
> > 
> > I think this function only applies to "modifier keys". It was tested
> > with arrow keys.
> 
> It should work for all keys.
> 
> > Anyway I don't think it's a big issue, since it doesn't cause
> > any big problem, and it doesn't happen very often. It was just a
> > situation where Windows and Wine exhibited slightly different
> > behavior.
> > 
> > The first bug is much more annoying since one has to completely exit
> > the game each time.
> 
> My comment was targeting both problems that you mentioned.

Ok, I didn't understand what this function does with the arrow keys yet,
but I think I found out where the 0x40 comes from now:

In server/queue.c::update_input_key_state,
  down = (keystate == desktop->keystate) ? 0xc0 : 0x80;

When server/queue.c::set_input_key_state() is called with down=0,
0xc0 & ~0x80 = 0x40,
  keystate[key] &= ~0x80;

From dlls/winex11.drv/keyboard.c::X11DRV_KeymapNotify,
get_async_key_state does SERVER_START_REQ( get_key_state ) with
req->tid = 0. This retrieves the desktop->keystate.

When writing back changes, set_async_key_state calls
SERVER_START_REQ( set_key_state ) with req->tid = GetCurrentThreadId().
This should copy the 0x40 bits from the desktop's keystate to the
thread's keystate.