Mercurial > sdl-ios-xcode
view include/SDL_error.h @ 1259:36f24cdfcda7
te: Thu, 17 Apr 2003 11:25:26 -0700
From: "Jim"
Subject: [SDL] Frame buffer patches...
Would seem that GCC 3.2.2 promotes all signed values to unsigned if any single vlaue is unsigned in an expression...
for instance when calculating an elo touch position....evertyhign is an (int) except for cach_vinfo.xres which is unsigned. THerefore if y
ou reverse the SDL_ELO_MIN_X and SDL_ELO_MAX_X values the resulging negative value pegs the expression to it's max. Attached it the accumu
lated patch to typecast the unsigned values to (int)
- *dx = (cache_vinfo.xres - (cache_vinfo.xres * (input_x - ELO_MIN_X)) / width);
+ *dx = ((int)cache_vinfo.xres - ((int)cache_vinfo.xres * (input_x - ELO_MIN_X)) / width);
and also to provide quite failure to operations which have the screen currently locked...
The touch screen I'm using the original values were exactly opposite of any position I touched on the screen - evaluating the math the expr
ession SHOULD have handled reversing the min and max values - and after casting the unsigned .xres and .yres to a signed int - worked well.
..
Jim
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Tue, 24 Jan 2006 06:36:43 +0000 |
parents | 9c55b00f8251 |
children | c9b51268668f |
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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 */ #ifdef SAVE_RCSID static char rcsid = "@(#) $Id$"; #endif /* Simple error message routines for SDL */ #ifndef _SDL_error_h #define _SDL_error_h #include "begin_code.h" /* Set up for C function definitions, even when using C++ */ #ifdef __cplusplus extern "C" { #endif /* Public functions */ extern DECLSPEC void SDLCALL SDL_SetError(const char *fmt, ...); extern DECLSPEC char * SDLCALL SDL_GetError(void); extern DECLSPEC void SDLCALL SDL_ClearError(void); /* Private error message function - used internally */ #define SDL_OutOfMemory() SDL_Error(SDL_ENOMEM) typedef enum { SDL_ENOMEM, SDL_EFREAD, SDL_EFWRITE, SDL_EFSEEK, SDL_LASTERROR } SDL_errorcode; extern DECLSPEC void SDLCALL SDL_Error(SDL_errorcode code); /* Ends C function definitions when using C++ */ #ifdef __cplusplus } #endif #include "close_code.h" #endif /* _SDL_error_h */