Mercurial > sdl-ios-xcode
view src/video/nanox/SDL_nxwm.c @ 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 | d910939febfa |
children | 782fd950bd46 c121d94672cb a1b03ba2fcd0 |
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/* SDL - Simple DirectMedia Layer Copyright (C) 1997-2004 Sam Lantinga Copyright (C) 2001 Hsieh-Fu Tsai This library is free software; you can redistribute it and/or modify it under the terms of the GNU Library General Public License as published by the Free Software Foundation; either version 2 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 Library General Public License for more details. You should have received a copy of the GNU Library General Public License along with this library; if not, write to the Free Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA Sam Lantinga slouken@libsdl.org Hsieh-Fu Tsai clare@setabox.com */ #include "SDL_config.h" #include "SDL_syswm.h" #include "../../events/SDL_events_c.h" #include "SDL_nxwm_c.h" void NX_SetCaption (_THIS, const char * title, const char * icon) { Dprintf ("enter NX_SetCaption\n") ; // Lock the event thread, in multi-threading environments SDL_Lock_EventThread () ; if (SDL_Window) GrSetWindowTitle (SDL_Window, title) ; SDL_Unlock_EventThread () ; Dprintf ("leave NX_SetCaption\n") ; } int NX_GetWMInfo (_THIS, SDL_SysWMinfo * info) { Dprintf ("enter NX_GetWMInfo\n") ; if (info -> version.major <= SDL_MAJOR_VERSION) { info -> window = SDL_Window ; return 1 ; } else { SDL_SetError("Application not compiled with SDL %d.%d\n", SDL_MAJOR_VERSION, SDL_MINOR_VERSION) ; return -1 ; } Dprintf ("leave NX_GetWMInfo\n") ; }