Mercurial > sdl-ios-xcode
view include/SDL_config.h.minimal @ 1544:ab1e4c41ab71
Fixed bug #33
Mike Frysinger wrote:
> with libsdl-1.2.9, some games (like bomberclone) started
> segfaulting in Gentoo
[...snip...]
> the last change in the last hunk:
[...snip...]
> if i change the statement to read:
> (table[which].blit_features & GetBlitFeatures()) == GetBlitFeatures()
> bomberclone no longer segfaults on my box
Alex Volkov wrote:
> The test "(table[which].blit_features & GetBlitFeatures()) ==
> table[which].blit_features)" is correct, and the previous
> "(table[which].cpu_mmx == SDL_HasMMX())" was actually broken.
I think there is potentially a slightly different cause of the above problem.
During the introduction of the Altivec code, the blit_table struct field
'alpha' got changed from a straightforward enum to a bitmask, which makes
perfect sense by itself. However, now the table driven blitter selection code
in SDL_CalculateBlitN() can choose the wrong blitters when searching for a
NO_ALPHA blitter because of the following code:
int a_need = 0;
...
(a_need & table[which].alpha) == a_need &&
When searching through the normal_blit_2[] table, a SET_ALPHA blitter (like
Blit_RGB565_ARGB8888) can now be selected instead of a NO_ALPHA one, causing
alpha channel bits to appear in a non-alpha destination surface. I suppose this
could theoretically be an indirect cause of the segfault mentioned above.
I *think* this can be fixed by changing to
int a_need = NO_ALPHA;
| author | Sam Lantinga <slouken@libsdl.org> |
|---|---|
| date | Wed, 15 Mar 2006 15:47:49 +0000 |
| parents | 30f189cdd82b |
| children |
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/* SDL - Simple DirectMedia Layer Copyright (C) 1997-2006 Sam Lantinga This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with this library; if not, write to the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA Sam Lantinga slouken@libsdl.org */ #ifndef _SDL_config_h #define _SDL_config_h #include "SDL_platform.h" /* Add any platform that doesn't build using the configure system */ #if defined(__AMIGA__) #include "SDL_config_amiga.h" #elif defined(__DREAMCAST__) #include "SDL_config_dreamcast.h" #elif defined(__MACOS__) #include "SDL_config_macos.h" #elif defined(__MACOSX__) #include "SDL_config_macosx.h" #elif defined(__WIN32__) #include "SDL_config_win32.h" #elif defined(__OS2__) #include "SDL_config_os2.h" #else /* This is the minimal configuration that can be used to build SDL */ #include <stdarg.h> typedef signed char int8_t; typedef unsigned char uint8_t; typedef signed short int16_t; typedef unsigned short uint16_t; typedef signed int int32_t; typedef unsigned int uint32_t; typedef unsigned int size_t; typedef unsigned long uintptr_t; /* Enable the dummy audio driver (src/audio/dummy/\*.c) */ #define SDL_AUDIO_DRIVER_DUMMY 1 /* Enable the stub cdrom driver (src/cdrom/dummy/\*.c) */ #define SDL_CDROM_DISABLED 1 /* Enable the stub joystick driver (src/joystick/dummy/\*.c) */ #define SDL_JOYSTICK_DISABLED 1 /* Enable the stub shared object loader (src/loadso/dummy/\*.c) */ #define SDL_LOADSO_DISABLED 1 /* Enable the stub thread support (src/thread/generic/\*.c) */ #define SDL_THREADS_DISABLED 1 /* Enable the stub timer support (src/timer/dummy/\*.c) */ #define SDL_TIMERS_DISABLED 1 /* Enable the dummy video driver (src/video/dummy/\*.c) */ #define SDL_VIDEO_DRIVER_DUMMY 1 #endif /* platform config */ #endif /* _SDL_config_h */