Re: GetKeyboardState problems in Age of Empires II

[Dmitry Timoshkov]

[please don't omit wine-devel when replying]

Stevie Trujillo  wrote:
> > Stevie Trujillo  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.

GetKeyboardState problems in Age of Empires II

[Stevie Trujillo]

On Thu, 18 Apr 2013 17:39:33 +0900
Dmitry Timoshkov  wrote:
> [please don't omit wine-devel when replying]
>
> Stevie Trujillo  wrote:
> > > Stevie Trujillo  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.

GetKeyboardState problems in Age of Empires II

[Stevie Trujillo]

I tried to make a test case now. It's tested on wine-1.5.27 since I 
don't have enough battery to compile new wine.

$ winegcc test.c -o test

Issue1, the 0x40 bit:
$ ./test.exe
00 00 00 00
00 00 00 00
*press LEFT arrow*
81 00 00 00
*release LEFT arrow*
01 00 00 00
*ALTTAB*
41 00 00 00

Issue2, LEFT ARROW remains pressed if released in another window.
$ ./test.exe
00 00 00 00
*press LEFT ARROW*
81 00 00 00
*ALTTAB*
c1 00 00 00
*RELEASE LEFT ARROW (outside Wine application)*
c1 00 00 00
*ALTTAB BACK*
c1 00 00 00
*press LEFT ARROW again (inside Wine application)*
41 00 00 00

test.c (also at http://pastie.org/7642788 if my mail client breaks it):
// based on http://www.winprog.org/tutorial/simple_window.html
#include <windows.h>
#include <stdio.h>

static const char g_szClassName[] = "myWindowClass";

static void print_keyboard_state()
{
BYTE keystate[256];
GetKeyboardState(keystate);
printf("%02x %02x %02x %02x\n", keystate[VK_LEFT], keystate[VK_UP], 
keystate[VK_RIGHT], keystate[VK_DOWN]);
}

// Step 4: the Window Procedure
static LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, WPARAM wParam, 
LPARAM lParam)
{
switch(msg)
{
    case WM_TIMER:
    	print_keyboard_state();
    break;
    case WM_CLOSE:
    	DestroyWindow(hwnd);
    break;
    case WM_DESTROY:
    	PostQuitMessage(0);
    break;
    default:
    	return DefWindowProc(hwnd, msg, wParam, lParam);
}
return 0;
}

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,
     LPSTR lpCmdLine, int nCmdShow)
{
WNDCLASSEX wc;
HWND hwnd;
MSG Msg;

//Step 1: Registering the Window Class
wc.cbSize        = sizeof(WNDCLASSEX);
wc.style         = 0;
wc.lpfnWndProc   = WndProc;
wc.cbClsExtra    = 0;
wc.cbWndExtra    = 0;
wc.hInstance     = hInstance;
wc.hIcon         = LoadIcon(NULL, IDI_APPLICATION);
wc.hCursor       = LoadCursor(NULL, IDC_ARROW);
wc.hbrBackground = (HBRUSH)(COLOR_WINDOW+1);
wc.lpszMenuName  = NULL;
wc.lpszClassName = g_szClassName;
wc.hIconSm       = LoadIcon(NULL, IDI_APPLICATION);

if(!RegisterClassEx(&wc))
    return 1;

// Step 2: Creating the Window
hwnd = CreateWindowEx(
     WS_EX_CLIENTEDGE,
     g_szClassName,
     "The title of my window",
     WS_OVERLAPPEDWINDOW,
     CW_USEDEFAULT, CW_USEDEFAULT, 240, 120,
     NULL, NULL, hInstance, NULL);

if(hwnd == NULL)
    return 1;

ShowWindow(hwnd, nCmdShow);
UpdateWindow(hwnd);

UINT id;
SetTimer(hwnd, 0, 1000, NULL);

// Step 3: The Message Loop
while(GetMessage(&Msg, NULL, 0, 0) > 0)
{
    TranslateMessage(&Msg);
    DispatchMessage(&Msg);
}
return Msg.wParam;
}