win32u: Return -1 for NUMCOLORS with 8-bit display DCs.

According to tests, GetDeviceCaps(NUMCOLORS) returns -1 for display DCs when the current display
mode is 8-bit on newer versions of Windows, which makes sense because lower bit depth display modes
are actually emulated with 32-bit modes.

Wine-Bug: https://bugs.winehq.org/show_bug.cgi?id=52679
Signed-off-by: Zhiyi Zhang <zzhang@codeweavers.com>
Signed-off-by: Huw Davies <huw@codeweavers.com>
Signed-off-by: Alexandre Julliard <julliard@winehq.org>
This commit is contained in:
Zhiyi Zhang 2022-04-18 14:55:48 +08:00 committed by Alexandre Julliard
parent bfed433024
commit a1dda8c376
2 changed files with 3 additions and 2 deletions

View File

@ -3,6 +3,7 @@
*
* Copyright 2005 Huw Davies
* Copyright 2008 Dmitry Timoshkov
* Copyright 2019-2022 Zhiyi Zhang for CodeWeavers
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
@ -2314,7 +2315,6 @@ static void test_display_dc(void)
value = GetDeviceCaps(hdc, NUMCOLORS);
if (bpps[i] > 8 || (bpps[i] == 8 && LOBYTE(LOWORD(GetVersion())) >= 6))
todo_wine_if(bpps[i] == 8 && LOBYTE(LOWORD(GetVersion())) >= 6)
ok(value == -1, "Expected -1, got %d.\n", value);
else if (bpps[i] == 8 && LOBYTE(LOWORD(GetVersion())) < 6)
ok(value > 16 && value <= 256, "Got %d.\n", value);

View File

@ -294,7 +294,8 @@ static INT CDECL nulldrv_GetDeviceCaps( PHYSDEV dev, INT cap )
case LOGPIXELSY: return get_system_dpi();
case NUMCOLORS:
bpp = NtGdiGetDeviceCaps( dev->hdc, BITSPIXEL );
return (bpp > 8) ? -1 : (1 << bpp);
/* Newer versions of Windows return -1 for 8-bit and higher */
return (bpp > 4) ? -1 : (1 << bpp);
case COLORRES:
/* The observed correspondence between BITSPIXEL and COLORRES is:
* BITSPIXEL: 8 -> COLORRES: 18