Mercurial > sdl-ios-xcode
view include/SDL_platform.h @ 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 | 993ef9ff4688 |
children | 57431b199aed |
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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 */ /* Try to get a standard set of platform defines */ #ifndef _SDL_platform_h #define _SDL_platform_h #if defined(_AIX) #undef __AIX__ #define __AIX__ 1 #endif #if defined(AMIGA) || defined(__AMIGA) || defined(__amigados__) #undef __AMIGA__ #define __AMIGA__ 1 #endif #if defined(__BEOS__) #undef __BEOS__ #define __BEOS__ 1 #endif #if defined(bsdi) || defined(__bsdi) || defined(__bsdi__) #undef __BSDI__ #define __BSDI__ 1 #endif #if defined(_arch_dreamcast) #undef __DREAMCAST__ #define __DREAMCAST__ 1 #endif #if defined(__FreeBSD__) #undef __FREEBSD__ #define __FREEBSD__ 1 #endif #if defined(hpux) || defined(__hpux) || defined(__hpux__) #undef __HPUX__ #define __HPUX__ 1 #endif #if defined(sgi) || defined(__sgi) || defined(__sgi__) || defined(_SGI_SOURCE) #undef __IRIX__ #define __IRIX__ 1 #endif #if defined(linux) || defined(__linux) || defined(__linux__) #undef __LINUX__ #define __LINUX__ 1 #endif #if defined(macintosh) #undef __MACOS__ #define __MACOS__ 1 #define TARGET_API_MAC_OS8 1 #define TARGET_API_MAC_CARBON 0 #define TARGET_API_MAC_OSX 0 #endif #if defined(__GNUC__) && (defined(__APPLE_CC__) || defined(__APPLE_CPP__)) #undef __MACOSX__ #define __MACOSX__ 1 #define TARGET_API_MAC_OS8 0 #define TARGET_API_MAC_CARBON 1 #define TARGET_API_MAC_OSX 1 #endif #if defined(__NetBSD__) #undef __NETBSD__ #define __NETBSD__ 1 #endif #if defined(__OpenBSD__) #undef __OPENBSD__ #define __OPENBSD__ 1 #endif #if defined(__OS2__) #undef __OS2__ #define __OS2__ 1 #endif #if defined(osf) || defined(__osf) || defined(__osf__) || defined(_OSF_SOURCE) #undef __OSF__ #define __OSF__ 1 #endif #if defined(__QNXNTO__) #undef __QNXNTO__ #define __QNXNTO__ 1 #endif #if defined(riscos) || defined(__riscos) || defined(__riscos__) #undef __RISCOS__ #define __RISCOS__ 1 #endif #if defined(solaris) || defined(__solaris) || defined(__solaris__) #undef __SOLARIS__ #define __SOLARIS__ 1 #endif #if defined(WIN32) || defined(_WIN32) #undef __WIN32__ #define __WIN32__ 1 #endif #endif /* _SDL_platform_h */