Mercurial > sdl-ios-xcode
annotate src/joystick/dummy/SDL_sysjoystick.c @ 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 | 435c2e481299 |
| children | c9b51268668f |
| rev | line source |
|---|---|
| 0 | 1 /* |
| 2 SDL - Simple DirectMedia Layer | |
|
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b8d311d90021
Updated copyright information for 2004 (Happy New Year!)
Sam Lantinga <slouken@libsdl.org>
parents:
297
diff
changeset
|
3 Copyright (C) 1997-2004 Sam Lantinga |
| 0 | 4 |
| 5 This library is free software; you can redistribute it and/or | |
| 6 modify it under the terms of the GNU Library General Public | |
| 7 License as published by the Free Software Foundation; either | |
| 8 version 2 of the License, or (at your option) any later version. | |
| 9 | |
| 10 This library is distributed in the hope that it will be useful, | |
| 11 but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| 13 Library General Public License for more details. | |
| 14 | |
| 15 You should have received a copy of the GNU Library General Public | |
| 16 License along with this library; if not, write to the Free | |
| 17 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
| 18 | |
| 19 Sam Lantinga | |
|
252
e8157fcb3114
Updated the source with the correct e-mail address
Sam Lantinga <slouken@libsdl.org>
parents:
0
diff
changeset
|
20 slouken@libsdl.org |
| 0 | 21 */ |
| 22 | |
| 23 #ifdef SAVE_RCSID | |
| 24 static char rcsid = | |
| 25 "@(#) $Id$"; | |
| 26 #endif | |
| 27 | |
| 28 /* This is the system specific header for the SDL joystick API */ | |
| 29 | |
| 30 #include <stdio.h> /* For the definition of NULL */ | |
| 31 | |
| 32 #include "SDL_error.h" | |
| 33 #include "SDL_joystick.h" | |
| 34 #include "SDL_sysjoystick.h" | |
| 35 #include "SDL_joystick_c.h" | |
| 36 | |
| 37 /* Function to scan the system for joysticks. | |
| 38 * This function should set SDL_numjoysticks to the number of available | |
| 39 * joysticks. Joystick 0 should be the system default joystick. | |
| 40 * It should return 0, or -1 on an unrecoverable fatal error. | |
| 41 */ | |
| 42 int SDL_SYS_JoystickInit(void) | |
| 43 { | |
| 44 SDL_numjoysticks = 0; | |
| 45 return(0); | |
| 46 } | |
| 47 | |
| 48 /* Function to get the device-dependent name of a joystick */ | |
| 49 const char *SDL_SYS_JoystickName(int index) | |
| 50 { | |
| 51 SDL_SetError("Logic error: No joysticks available"); | |
| 52 return(NULL); | |
| 53 } | |
| 54 | |
| 55 /* Function to open a joystick for use. | |
| 56 The joystick to open is specified by the index field of the joystick. | |
| 57 This should fill the nbuttons and naxes fields of the joystick structure. | |
| 58 It returns 0, or -1 if there is an error. | |
| 59 */ | |
| 60 int SDL_SYS_JoystickOpen(SDL_Joystick *joystick) | |
| 61 { | |
| 62 SDL_SetError("Logic error: No joysticks available"); | |
| 63 return(-1); | |
| 64 } | |
| 65 | |
| 66 /* Function to update the state of a joystick - called as a device poll. | |
| 67 * This function shouldn't update the joystick structure directly, | |
| 68 * but instead should call SDL_PrivateJoystick*() to deliver events | |
| 69 * and update joystick device state. | |
| 70 */ | |
| 71 void SDL_SYS_JoystickUpdate(SDL_Joystick *joystick) | |
| 72 { | |
| 73 return; | |
| 74 } | |
| 75 | |
| 76 /* Function to close a joystick after use */ | |
| 77 void SDL_SYS_JoystickClose(SDL_Joystick *joystick) | |
| 78 { | |
| 79 return; | |
| 80 } | |
| 81 | |
| 82 /* Function to perform any system-specific joystick related cleanup */ | |
| 83 void SDL_SYS_JoystickQuit(void) | |
| 84 { | |
| 85 return; | |
| 86 } | |
| 87 |