Mercurial > sdl-ios-xcode
view src/video/xbios/SDL_xbios_blowup.h @ 3899:081aecdb0911 SDL-1.2
From: Gabriel Gambetta
To: SDL Mailing List <sdl@libsdl.org>
Date: Fri, 17 Nov 2006 00:39:29 -0200
Subject: [SDL] Alpha blending bug - fixed?
It turns out mm5 never got the correct value. This failed :
[...]
"movd %1, %%mm5\n\t"
: : "m" (amask), "m" (sf->Ashift) );
mm5 got 0xFF000018 instead of 0x00000018. However I did this :
Uint32 ashift = sf->Ashift;
[...]
"movd %1, %%mm5\n\t"
: : "m" (amask), "m" (ashift) );
and everything worked fine.
The only thing I could find out was that ashift is 32-bit aligned but
sf->Ashift isn't:
printf("ashift %8X [%d]\n", &ashift, (int)(&ashift) % 4);
printf("sf->Ashift %8X [%d]\n", &sf->Ashift, (int)(&sf->Ashift) % 4);
ashift at BFF0E0C4 [0]
sf->Ashift at 08AFB9CD [1]
Could this be the problem? If it is, the fix is extremely trivial.
Should I submit a patch?
--Gabriel
author | Ryan C. Gordon <icculus@icculus.org> |
---|---|
date | Tue, 21 Nov 2006 23:17:00 +0000 |
parents | d910939febfa |
children | 782fd950bd46 c121d94672cb a1b03ba2fcd0 |
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/* SDL - Simple DirectMedia Layer Copyright (C) 1997-2004 Sam Lantinga 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 */ #include "SDL_config.h" /* Blowup extension definitions Patrice Mandin */ #ifndef _SDL_xbios_blowup_h #define _SDL_xbios_blowup_h #include "SDL_xbios.h" /*--- Types ---*/ typedef struct { /* 64 bytes */ unsigned short enabled; /* Extended mode enabled ? 0=yes, <>0=no */ unsigned short dummy10[6]; unsigned short registers_0E; /* value for register 0xffff820e */ unsigned short registers_10; /* value for register 0xffff8210 */ unsigned short dummy11[23]; /* 64 bytes */ unsigned short width; /* width-1 */ unsigned short height; /* height-1 */ unsigned short dummy20; unsigned long screensize; /* screensize in bytes */ unsigned short dummy21[8]; unsigned short virtual; /* Virtual screen ? */ unsigned short virwidth; /* Virtual screen width */ unsigned short virheight; /* Virtual screen height */ unsigned short dummy22; unsigned short monitor; /* Monitor defined for this mode */ unsigned short extension; /* Extended mode defined ? 0=yes, 1=no */ unsigned short dummy23[13]; /* 64 bytes */ unsigned short dummy30; unsigned short registers_82[6]; /* values for registers 0xffff8282-8c */ unsigned short dummy31[9]; unsigned short dummy32; unsigned short registers_A2[6]; /* values for registers 0xffff82a2-ac */ unsigned short dummy33[9]; /* 64 bytes */ unsigned short registers_C0; /* value for register 0xffff82c0 */ unsigned short registers_C2; /* value for register 0xffff82c2 */ unsigned short dummy40[30]; } __attribute__((packed)) blow_mode_t; typedef struct { blow_mode_t blowup_modes[10]; unsigned char num_mode[6]; unsigned long dummy; unsigned short montype; } __attribute__((packed)) blow_cookie_t; /*--- Functions prototypes ---*/ void SDL_XBIOS_BlowupInit(_THIS, blow_cookie_t *cookie_blow); #endif /* _SDL_xbios_blowup_h */