view include/begin_code.h @ 1212:7663bb0f52c7

To: sdl@libsdl.org From: Christian Walther <cwalther@gmx.ch> Date: Thu, 15 Dec 2005 21:19:53 +0100 Subject: [SDL] More mouse enhancements for Mac OS X The attached patch brings two more enhancements to mouse handling on Mac OS X (Quartz): 1. Currently, after launching an SDL application, SDL's notion of the mouse position is stuck in the top left corner (0,0) until the first time the mouse is moved. That's because the UpdateMouse() function isn't implemented in the Quartz driver. This patch adds it. 2. When grabbing input while the mouse cursor is hidden, the function CGAssociateMouseAndMouseCursorPosition(0) is called, which prevents the system's notion of the mouse location from moving (and therefore leaving the SDL window) even when the mouse is moved. However, apparently the Wacom tablet driver (and maybe other special pointing device drivers) doesn't care about that setting and still allows the mouse location to go outside of the window. Interestingly, the system cursor, which is made visible by the existing code in SDL in that case, does not follow the mouse location, but appears in the middle of the SDL window. The mouse location being outside of the window however means that mouse button events go to background applications (or the dock or whatever is there), which is very confusing to the user who sees no cursor outside of the SDL window. I have not found any way of intercepting these events (and that's probably by design, as "normal" applications shouldn't prevent the user from bringing other applications' windows to the front by clicking on them). An idea would be placing a fully transparent, screen-filling window in front of everything, but I fear that this might affect rendering performance (by doing unnecessary compositing, using up memory, or whatever). The deluxe solution to the problem would be talking to the tablet driver using AppleEvents to tell it to constrain its mapped area to the window (see Wacom's "TabletEventDemo" sample app, http://www.wacomeng.com/devsupport/mac/downloads.html), but I think that the bloat that solution would add to SDL would outweigh its usefulness. What I did instead in my patch is reassociating mouse and cursor when the mouse leaves the window while an invisible grab is in effect, and restoring the grab when the window is entered. That way, the grab can still be effectively broken by a tablet, but at least it's obvious to the user that it is broken. That change is minimal - it doesn't affect operation with a mouse (or a trackpad), and the code that it adds is not executed on every PumpEvents() call, only when entering and leaving the window. Unless there are any concerns about the patch, please apply. Feel free to shorten the lengthy comment in SDL_QuartzEvents.m if you think it's too verbose. Thanks -Christian
author Ryan C. Gordon <icculus@icculus.org>
date Mon, 02 Jan 2006 00:31:00 +0000
parents 173c063d4f55
children d910939febfa
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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
*/

/* This file sets things up for C dynamic library function definitions,
   static inlined functions, and structures aligned at 4-byte alignment.
   If you don't like ugly C preprocessor code, don't look at this file. :)
*/

/* This shouldn't be nested -- included it around code only. */
#ifdef _begin_code_h
#error Nested inclusion of begin_code.h
#endif
#define _begin_code_h

/* Make sure the correct platform symbols are defined */
#if !defined(WIN32) && defined(_WIN32)
#define WIN32
#endif /* Windows */

/* Some compilers use a special export keyword */
#ifndef DECLSPEC
# ifdef __BEOS__
#  if defined(__GNUC__)
#   define DECLSPEC	__declspec(dllexport)
#  else
#   define DECLSPEC	__declspec(export)
#  endif
# else
# ifdef WIN32
#  ifdef __BORLANDC__
#   ifdef BUILD_SDL
#    define DECLSPEC 
#   else
#    define DECLSPEC __declspec(dllimport)
#   endif
#  else
#   define DECLSPEC	__declspec(dllexport)
#  endif
# else
# ifdef __OS2__
#  ifdef __WATCOMC__
#   ifdef BUILD_SDL
#    define DECLSPEC __declspec(dllexport)
#   else
#  define DECLSPEC
# endif
#  else
#   define DECLSPEC
#  endif
# else
#  define DECLSPEC
# endif
# endif
# endif
#endif

/* By default SDL uses the C calling convention */
#ifndef SDLCALL
#if defined(WIN32) && !defined(__GNUC__)
#define SDLCALL __cdecl
#else
#ifdef __OS2__
/* But on OS/2, we use the _System calling convention */
/* to be compatible with every compiler */
#define SDLCALL _System
#else
#define SDLCALL
#endif
#endif
#endif /* SDLCALL */

/* Removed DECLSPEC on Symbian OS because SDL cannot be a DLL in EPOC */
#ifdef __SYMBIAN32__ 
#undef DECLSPEC
#define DECLSPEC
#endif /* __SYMBIAN32__ */

/* Force structure packing at 4 byte alignment.
   This is necessary if the header is included in code which has structure
   packing set to an alternate value, say for loading structures from disk.
   The packing is reset to the previous value in close_code.h
 */
#if defined(_MSC_VER) || defined(__MWERKS__) || defined(__BORLANDC__)
#ifdef _MSC_VER
#pragma warning(disable: 4103)
#endif
#ifdef __BORLANDC__
#pragma nopackwarning
#endif
#pragma pack(push,4)
#elif (defined(__MWERKS__) && defined(macintosh))
#pragma options align=mac68k4byte
#pragma enumsalwaysint on
#endif /* Compiler needs structure packing set */

/* Set up compiler-specific options for inlining functions */
#ifndef SDL_INLINE_OKAY
#ifdef __GNUC__
#define SDL_INLINE_OKAY
#else
/* Add any special compiler-specific cases here */
#if defined(_MSC_VER) || defined(__BORLANDC__) || \
    defined(__DMC__) || defined(__SC__) || \
    defined(__WATCOMC__) || defined(__LCC__) || \
    defined(__DECC)
#ifndef __inline__
#define __inline__	__inline
#endif
#define SDL_INLINE_OKAY
#else
#if !defined(__MRC__) && !defined(_SGI_SOURCE)
#define __inline__ inline
#define SDL_INLINE_OKAY
#endif /* Not a funky compiler */
#endif /* Visual C++ */
#endif /* GNU C */
#endif /* SDL_INLINE_OKAY */

/* If inlining isn't supported, remove "__inline__", turning static
   inlined functions into static functions (resulting in code bloat
   in all files which include the offending header files)
*/
#ifndef SDL_INLINE_OKAY
#define __inline__
#endif

/* Apparently this is needed by several Windows compilers */
#if !defined(__MACH__)
#ifndef NULL
#ifdef __cplusplus
#define NULL 0
#else
#define NULL ((void *)0)
#endif
#endif /* NULL */
#endif /* ! MacOS X - breaks precompiled headers */