include/SDL_hints.h
author Philipp Wiesemann <philipp.wiesemann@arcor.de>
Thu, 05 May 2016 22:04:16 +0200
changeset 10161 c0c399499591
parent 10140 6dd5f49e4a77
child 10213 f97a7faf0b58
permissions -rw-r--r--
Updated documentation of SDL_HINT_THREAD_STACK_SIZE in header file.
     1 /*
     2   Simple DirectMedia Layer
     3   Copyright (C) 1997-2016 Sam Lantinga <slouken@libsdl.org>
     4 
     5   This software is provided 'as-is', without any express or implied
     6   warranty.  In no event will the authors be held liable for any damages
     7   arising from the use of this software.
     8 
     9   Permission is granted to anyone to use this software for any purpose,
    10   including commercial applications, and to alter it and redistribute it
    11   freely, subject to the following restrictions:
    12 
    13   1. The origin of this software must not be misrepresented; you must not
    14      claim that you wrote the original software. If you use this software
    15      in a product, an acknowledgment in the product documentation would be
    16      appreciated but is not required.
    17   2. Altered source versions must be plainly marked as such, and must not be
    18      misrepresented as being the original software.
    19   3. This notice may not be removed or altered from any source distribution.
    20 */
    21 
    22 /**
    23  *  \file SDL_hints.h
    24  *
    25  *  Official documentation for SDL configuration variables
    26  *
    27  *  This file contains functions to set and get configuration hints,
    28  *  as well as listing each of them alphabetically.
    29  *
    30  *  The convention for naming hints is SDL_HINT_X, where "SDL_X" is
    31  *  the environment variable that can be used to override the default.
    32  *
    33  *  In general these hints are just that - they may or may not be
    34  *  supported or applicable on any given platform, but they provide
    35  *  a way for an application or user to give the library a hint as
    36  *  to how they would like the library to work.
    37  */
    38 
    39 #ifndef _SDL_hints_h
    40 #define _SDL_hints_h
    41 
    42 #include "SDL_stdinc.h"
    43 
    44 #include "begin_code.h"
    45 /* Set up for C function definitions, even when using C++ */
    46 #ifdef __cplusplus
    47 extern "C" {
    48 #endif
    49 
    50 /**
    51  *  \brief  A variable controlling how 3D acceleration is used to accelerate the SDL screen surface.
    52  *
    53  *  SDL can try to accelerate the SDL screen surface by using streaming
    54  *  textures with a 3D rendering engine.  This variable controls whether and
    55  *  how this is done.
    56  *
    57  *  This variable can be set to the following values:
    58  *    "0"       - Disable 3D acceleration
    59  *    "1"       - Enable 3D acceleration, using the default renderer.
    60  *    "X"       - Enable 3D acceleration, using X where X is one of the valid rendering drivers.  (e.g. "direct3d", "opengl", etc.)
    61  *
    62  *  By default SDL tries to make a best guess for each platform whether
    63  *  to use acceleration or not.
    64  */
    65 #define SDL_HINT_FRAMEBUFFER_ACCELERATION   "SDL_FRAMEBUFFER_ACCELERATION"
    66 
    67 /**
    68  *  \brief  A variable specifying which render driver to use.
    69  *
    70  *  If the application doesn't pick a specific renderer to use, this variable
    71  *  specifies the name of the preferred renderer.  If the preferred renderer
    72  *  can't be initialized, the normal default renderer is used.
    73  *
    74  *  This variable is case insensitive and can be set to the following values:
    75  *    "direct3d"
    76  *    "opengl"
    77  *    "opengles2"
    78  *    "opengles"
    79  *    "software"
    80  *
    81  *  The default varies by platform, but it's the first one in the list that
    82  *  is available on the current platform.
    83  */
    84 #define SDL_HINT_RENDER_DRIVER              "SDL_RENDER_DRIVER"
    85 
    86 /**
    87  *  \brief  A variable controlling whether the OpenGL render driver uses shaders if they are available.
    88  *
    89  *  This variable can be set to the following values:
    90  *    "0"       - Disable shaders
    91  *    "1"       - Enable shaders
    92  *
    93  *  By default shaders are used if OpenGL supports them.
    94  */
    95 #define SDL_HINT_RENDER_OPENGL_SHADERS      "SDL_RENDER_OPENGL_SHADERS"
    96 
    97 /**
    98  *  \brief  A variable controlling whether the Direct3D device is initialized for thread-safe operations.
    99  *
   100  *  This variable can be set to the following values:
   101  *    "0"       - Thread-safety is not enabled (faster)
   102  *    "1"       - Thread-safety is enabled
   103  *
   104  *  By default the Direct3D device is created with thread-safety disabled.
   105  */
   106 #define SDL_HINT_RENDER_DIRECT3D_THREADSAFE "SDL_RENDER_DIRECT3D_THREADSAFE"
   107 
   108 /**
   109  *  \brief  A variable controlling whether to enable Direct3D 11+'s Debug Layer.
   110  *
   111  *  This variable does not have any effect on the Direct3D 9 based renderer.
   112  *
   113  *  This variable can be set to the following values:
   114  *    "0"       - Disable Debug Layer use
   115  *    "1"       - Enable Debug Layer use
   116  *
   117  *  By default, SDL does not use Direct3D Debug Layer.
   118  */
   119 #define SDL_HINT_RENDER_DIRECT3D11_DEBUG    "SDL_RENDER_DIRECT3D11_DEBUG"
   120 
   121 /**
   122  *  \brief  A variable controlling the scaling quality
   123  *
   124  *  This variable can be set to the following values:
   125  *    "0" or "nearest" - Nearest pixel sampling
   126  *    "1" or "linear"  - Linear filtering (supported by OpenGL and Direct3D)
   127  *    "2" or "best"    - Currently this is the same as "linear"
   128  *
   129  *  By default nearest pixel sampling is used
   130  */
   131 #define SDL_HINT_RENDER_SCALE_QUALITY       "SDL_RENDER_SCALE_QUALITY"
   132 
   133 /**
   134  *  \brief  A variable controlling whether updates to the SDL screen surface should be synchronized with the vertical refresh, to avoid tearing.
   135  *
   136  *  This variable can be set to the following values:
   137  *    "0"       - Disable vsync
   138  *    "1"       - Enable vsync
   139  *
   140  *  By default SDL does not sync screen surface updates with vertical refresh.
   141  */
   142 #define SDL_HINT_RENDER_VSYNC               "SDL_RENDER_VSYNC"
   143 
   144 /**
   145  *  \brief  A variable controlling whether the screensaver is enabled. 
   146  *
   147  *  This variable can be set to the following values:
   148  *    "0"       - Disable screensaver
   149  *    "1"       - Enable screensaver
   150  *
   151  *  By default SDL will disable the screensaver.
   152  */
   153 #define SDL_HINT_VIDEO_ALLOW_SCREENSAVER    "SDL_VIDEO_ALLOW_SCREENSAVER"
   154 
   155 /**
   156  *  \brief  A variable controlling whether the X11 VidMode extension should be used.
   157  *
   158  *  This variable can be set to the following values:
   159  *    "0"       - Disable XVidMode
   160  *    "1"       - Enable XVidMode
   161  *
   162  *  By default SDL will use XVidMode if it is available.
   163  */
   164 #define SDL_HINT_VIDEO_X11_XVIDMODE         "SDL_VIDEO_X11_XVIDMODE"
   165 
   166 /**
   167  *  \brief  A variable controlling whether the X11 Xinerama extension should be used.
   168  *
   169  *  This variable can be set to the following values:
   170  *    "0"       - Disable Xinerama
   171  *    "1"       - Enable Xinerama
   172  *
   173  *  By default SDL will use Xinerama if it is available.
   174  */
   175 #define SDL_HINT_VIDEO_X11_XINERAMA         "SDL_VIDEO_X11_XINERAMA"
   176 
   177 /**
   178  *  \brief  A variable controlling whether the X11 XRandR extension should be used.
   179  *
   180  *  This variable can be set to the following values:
   181  *    "0"       - Disable XRandR
   182  *    "1"       - Enable XRandR
   183  *
   184  *  By default SDL will not use XRandR because of window manager issues.
   185  */
   186 #define SDL_HINT_VIDEO_X11_XRANDR           "SDL_VIDEO_X11_XRANDR"
   187 
   188 /**
   189  *  \brief  A variable controlling whether the X11 _NET_WM_PING protocol should be supported.
   190  *
   191  *  This variable can be set to the following values:
   192  *    "0"       - Disable _NET_WM_PING
   193  *    "1"       - Enable _NET_WM_PING
   194  *
   195  *  By default SDL will use _NET_WM_PING, but for applications that know they
   196  *  will not always be able to respond to ping requests in a timely manner they can
   197  *  turn it off to avoid the window manager thinking the app is hung.
   198  *  The hint is checked in CreateWindow.
   199  */
   200 #define SDL_HINT_VIDEO_X11_NET_WM_PING      "SDL_VIDEO_X11_NET_WM_PING"
   201 
   202 /**
   203  *  \brief  A variable controlling whether the window frame and title bar are interactive when the cursor is hidden 
   204  *
   205  *  This variable can be set to the following values:
   206  *    "0"       - The window frame is not interactive when the cursor is hidden (no move, resize, etc)
   207  *    "1"       - The window frame is interactive when the cursor is hidden
   208  *
   209  *  By default SDL will allow interaction with the window frame when the cursor is hidden
   210  */
   211 #define SDL_HINT_WINDOW_FRAME_USABLE_WHILE_CURSOR_HIDDEN    "SDL_WINDOW_FRAME_USABLE_WHILE_CURSOR_HIDDEN"
   212 
   213 /**
   214  *  \brief  A variable controlling whether the windows message loop is processed by SDL 
   215  *
   216  *  This variable can be set to the following values:
   217  *    "0"       - The window message loop is not run
   218  *    "1"       - The window message loop is processed in SDL_PumpEvents()
   219  *
   220  *  By default SDL will process the windows message loop
   221  */
   222 #define SDL_HINT_WINDOWS_ENABLE_MESSAGELOOP "SDL_WINDOWS_ENABLE_MESSAGELOOP"
   223 
   224 /**
   225  *  \brief  A variable controlling whether grabbing input grabs the keyboard
   226  *
   227  *  This variable can be set to the following values:
   228  *    "0"       - Grab will affect only the mouse
   229  *    "1"       - Grab will affect mouse and keyboard
   230  *
   231  *  By default SDL will not grab the keyboard so system shortcuts still work.
   232  */
   233 #define SDL_HINT_GRAB_KEYBOARD              "SDL_GRAB_KEYBOARD"
   234 
   235 /**
   236 *  \brief  A variable controlling whether relative mouse mode is implemented using mouse warping
   237 *
   238 *  This variable can be set to the following values:
   239 *    "0"       - Relative mouse mode uses raw input
   240 *    "1"       - Relative mouse mode uses mouse warping
   241 *
   242 *  By default SDL will use raw input for relative mouse mode
   243 */
   244 #define SDL_HINT_MOUSE_RELATIVE_MODE_WARP    "SDL_MOUSE_RELATIVE_MODE_WARP"
   245 
   246 /**
   247  *  \brief Minimize your SDL_Window if it loses key focus when in fullscreen mode. Defaults to true.
   248  *
   249  */
   250 #define SDL_HINT_VIDEO_MINIMIZE_ON_FOCUS_LOSS   "SDL_VIDEO_MINIMIZE_ON_FOCUS_LOSS"
   251 
   252 /**
   253  *  \brief  A variable controlling whether the idle timer is disabled on iOS.
   254  *
   255  *  When an iOS app does not receive touches for some time, the screen is
   256  *  dimmed automatically. For games where the accelerometer is the only input
   257  *  this is problematic. This functionality can be disabled by setting this
   258  *  hint.
   259  *
   260  *  As of SDL 2.0.4, SDL_EnableScreenSaver and SDL_DisableScreenSaver accomplish
   261  *  the same thing on iOS. They should be preferred over this hint.
   262  *
   263  *  This variable can be set to the following values:
   264  *    "0"       - Enable idle timer
   265  *    "1"       - Disable idle timer
   266  */
   267 #define SDL_HINT_IDLE_TIMER_DISABLED "SDL_IOS_IDLE_TIMER_DISABLED"
   268 
   269 /**
   270  *  \brief  A variable controlling which orientations are allowed on iOS.
   271  *
   272  *  In some circumstances it is necessary to be able to explicitly control
   273  *  which UI orientations are allowed.
   274  *
   275  *  This variable is a space delimited list of the following values:
   276  *    "LandscapeLeft", "LandscapeRight", "Portrait" "PortraitUpsideDown"
   277  */
   278 #define SDL_HINT_ORIENTATIONS "SDL_IOS_ORIENTATIONS"
   279     
   280 /**
   281  *  \brief  A variable controlling whether the Android / iOS built-in
   282  *  accelerometer should be listed as a joystick device, rather than listing
   283  *  actual joysticks only.
   284  *
   285  *  This variable can be set to the following values:
   286  *    "0"       - List only real joysticks and accept input from them
   287  *    "1"       - List real joysticks along with the accelerometer as if it were a 3 axis joystick (the default).
   288  */
   289 #define SDL_HINT_ACCELEROMETER_AS_JOYSTICK "SDL_ACCELEROMETER_AS_JOYSTICK"
   290 
   291 
   292 /**
   293  *  \brief  A variable that lets you disable the detection and use of Xinput gamepad devices
   294  *
   295  *  The variable can be set to the following values:
   296  *    "0"       - Disable XInput detection (only uses direct input)
   297  *    "1"       - Enable XInput detection (the default)
   298  */
   299 #define SDL_HINT_XINPUT_ENABLED "SDL_XINPUT_ENABLED"
   300 
   301 
   302 /**
   303  *  \brief  A variable that causes SDL to use the old axis and button mapping for XInput devices.
   304  *
   305  *  This hint is for backwards compatibility only and will be removed in SDL 2.1
   306  *
   307  *  The default value is "0".  This hint must be set before SDL_Init()
   308  */
   309 #define SDL_HINT_XINPUT_USE_OLD_JOYSTICK_MAPPING "SDL_XINPUT_USE_OLD_JOYSTICK_MAPPING"
   310 
   311 
   312 /**
   313  *  \brief  A variable that lets you manually hint extra gamecontroller db entries
   314  *
   315  *  The variable should be newline delimited rows of gamecontroller config data, see SDL_gamecontroller.h
   316  *
   317  *  This hint must be set before calling SDL_Init(SDL_INIT_GAMECONTROLLER)
   318  *  You can update mappings after the system is initialized with SDL_GameControllerMappingForGUID() and SDL_GameControllerAddMapping()
   319  */
   320 #define SDL_HINT_GAMECONTROLLERCONFIG "SDL_GAMECONTROLLERCONFIG"
   321 
   322 
   323 /**
   324  *  \brief  A variable that lets you enable joystick (and gamecontroller) events even when your app is in the background.
   325  *
   326  *  The variable can be set to the following values:
   327  *    "0"       - Disable joystick & gamecontroller input events when the
   328  *                application is in the background.
   329  *    "1"       - Enable joystick & gamecontroller input events when the
   330  *                application is in the background.
   331  *
   332  *  The default value is "0".  This hint may be set at any time.
   333  */
   334 #define SDL_HINT_JOYSTICK_ALLOW_BACKGROUND_EVENTS "SDL_JOYSTICK_ALLOW_BACKGROUND_EVENTS"
   335 
   336 
   337 /**
   338  *  \brief If set to "0" then never set the top most bit on a SDL Window, even if the video mode expects it.
   339  *      This is a debugging aid for developers and not expected to be used by end users. The default is "1"
   340  *
   341  *  This variable can be set to the following values:
   342  *    "0"       - don't allow topmost
   343  *    "1"       - allow topmost
   344  */
   345 #define SDL_HINT_ALLOW_TOPMOST "SDL_ALLOW_TOPMOST"
   346 
   347 
   348 /**
   349  *  \brief A variable that controls the timer resolution, in milliseconds.
   350  *
   351  *  The higher resolution the timer, the more frequently the CPU services
   352  *  timer interrupts, and the more precise delays are, but this takes up
   353  *  power and CPU time.  This hint is only used on Windows 7 and earlier.
   354  *
   355  *  See this blog post for more information:
   356  *  http://randomascii.wordpress.com/2013/07/08/windows-timer-resolution-megawatts-wasted/
   357  *
   358  *  If this variable is set to "0", the system timer resolution is not set.
   359  *
   360  *  The default value is "1". This hint may be set at any time.
   361  */
   362 #define SDL_HINT_TIMER_RESOLUTION "SDL_TIMER_RESOLUTION"
   363 
   364 
   365 
   366 /**
   367 *  \brief  A string specifying SDL's threads stack size in bytes or "0" for the backend's default size
   368 *
   369 *  Use this hint in case you need to set SDL's threads stack size to other than the default.
   370 *  This is specially useful if you build SDL against a non glibc libc library (such as musl) which
   371 *  provides a relatively small default thread stack size (a few kilobytes versus the default 8MB glibc uses).
   372 *  Support for this hint is currently available only in the pthread, Windows, and PSP backend.
   373 */
   374 #define SDL_HINT_THREAD_STACK_SIZE              "SDL_THREAD_STACK_SIZE"
   375 
   376 /**
   377  *  \brief If set to 1, then do not allow high-DPI windows. ("Retina" on Mac and iOS)
   378  */
   379 #define SDL_HINT_VIDEO_HIGHDPI_DISABLED "SDL_VIDEO_HIGHDPI_DISABLED"
   380 
   381 /**
   382  *  \brief A variable that determines whether ctrl+click should generate a right-click event on Mac
   383  *
   384  *  If present, holding ctrl while left clicking will generate a right click
   385  *  event when on Mac.
   386  */
   387 #define SDL_HINT_MAC_CTRL_CLICK_EMULATE_RIGHT_CLICK "SDL_MAC_CTRL_CLICK_EMULATE_RIGHT_CLICK"
   388 
   389 /**
   390 *  \brief  A variable specifying which shader compiler to preload when using the Chrome ANGLE binaries
   391 *
   392 *  SDL has EGL and OpenGL ES2 support on Windows via the ANGLE project. It
   393 *  can use two different sets of binaries, those compiled by the user from source
   394 *  or those provided by the Chrome browser. In the later case, these binaries require
   395 *  that SDL loads a DLL providing the shader compiler.
   396 *
   397 *  This variable can be set to the following values:
   398 *    "d3dcompiler_46.dll" - default, best for Vista or later.
   399 *    "d3dcompiler_43.dll" - for XP support.
   400 *    "none" - do not load any library, useful if you compiled ANGLE from source and included the compiler in your binaries.
   401 *
   402 */
   403 #define SDL_HINT_VIDEO_WIN_D3DCOMPILER              "SDL_VIDEO_WIN_D3DCOMPILER"
   404 
   405 /**
   406 *  \brief  A variable that is the address of another SDL_Window* (as a hex string formatted with "%p").
   407 *  
   408 *  If this hint is set before SDL_CreateWindowFrom() and the SDL_Window* it is set to has
   409 *  SDL_WINDOW_OPENGL set (and running on WGL only, currently), then two things will occur on the newly 
   410 *  created SDL_Window:
   411 *
   412 *  1. Its pixel format will be set to the same pixel format as this SDL_Window.  This is
   413 *  needed for example when sharing an OpenGL context across multiple windows.
   414 *
   415 *  2. The flag SDL_WINDOW_OPENGL will be set on the new window so it can be used for
   416 *  OpenGL rendering.
   417 *
   418 *  This variable can be set to the following values:
   419 *    The address (as a string "%p") of the SDL_Window* that new windows created with SDL_CreateWindowFrom() should
   420 *    share a pixel format with.
   421 */
   422 #define SDL_HINT_VIDEO_WINDOW_SHARE_PIXEL_FORMAT    "SDL_VIDEO_WINDOW_SHARE_PIXEL_FORMAT"
   423 
   424 /**
   425  *  \brief A URL to a WinRT app's privacy policy
   426  *
   427  *  All network-enabled WinRT apps must make a privacy policy available to its
   428  *  users.  On Windows 8, 8.1, and RT, Microsoft mandates that this policy be
   429  *  be available in the Windows Settings charm, as accessed from within the app.
   430  *  SDL provides code to add a URL-based link there, which can point to the app's
   431  *  privacy policy.
   432  *
   433  *  To setup a URL to an app's privacy policy, set SDL_HINT_WINRT_PRIVACY_POLICY_URL
   434  *  before calling any SDL_Init functions.  The contents of the hint should
   435  *  be a valid URL.  For example, "http://www.example.com".
   436  *
   437  *  The default value is "", which will prevent SDL from adding a privacy policy
   438  *  link to the Settings charm.  This hint should only be set during app init.
   439  *
   440  *  The label text of an app's "Privacy Policy" link may be customized via another
   441  *  hint, SDL_HINT_WINRT_PRIVACY_POLICY_LABEL.
   442  *
   443  *  Please note that on Windows Phone, Microsoft does not provide standard UI
   444  *  for displaying a privacy policy link, and as such, SDL_HINT_WINRT_PRIVACY_POLICY_URL
   445  *  will not get used on that platform.  Network-enabled phone apps should display
   446  *  their privacy policy through some other, in-app means.
   447  */
   448 #define SDL_HINT_WINRT_PRIVACY_POLICY_URL "SDL_WINRT_PRIVACY_POLICY_URL"
   449 
   450 /** \brief Label text for a WinRT app's privacy policy link
   451  *
   452  *  Network-enabled WinRT apps must include a privacy policy.  On Windows 8, 8.1, and RT,
   453  *  Microsoft mandates that this policy be available via the Windows Settings charm.
   454  *  SDL provides code to add a link there, with its label text being set via the
   455  *  optional hint, SDL_HINT_WINRT_PRIVACY_POLICY_LABEL.
   456  *
   457  *  Please note that a privacy policy's contents are not set via this hint.  A separate
   458  *  hint, SDL_HINT_WINRT_PRIVACY_POLICY_URL, is used to link to the actual text of the
   459  *  policy.
   460  *
   461  *  The contents of this hint should be encoded as a UTF8 string.
   462  *
   463  *  The default value is "Privacy Policy".  This hint should only be set during app
   464  *  initialization, preferably before any calls to SDL_Init.
   465  *
   466  *  For additional information on linking to a privacy policy, see the documentation for
   467  *  SDL_HINT_WINRT_PRIVACY_POLICY_URL.
   468  */
   469 #define SDL_HINT_WINRT_PRIVACY_POLICY_LABEL "SDL_WINRT_PRIVACY_POLICY_LABEL"
   470 
   471 /** \brief Allows back-button-press events on Windows Phone to be marked as handled
   472  *
   473  *  Windows Phone devices typically feature a Back button.  When pressed,
   474  *  the OS will emit back-button-press events, which apps are expected to
   475  *  handle in an appropriate manner.  If apps do not explicitly mark these
   476  *  events as 'Handled', then the OS will invoke its default behavior for
   477  *  unhandled back-button-press events, which on Windows Phone 8 and 8.1 is to
   478  *  terminate the app (and attempt to switch to the previous app, or to the
   479  *  device's home screen).
   480  *
   481  *  Setting the SDL_HINT_WINRT_HANDLE_BACK_BUTTON hint to "1" will cause SDL
   482  *  to mark back-button-press events as Handled, if and when one is sent to
   483  *  the app.
   484  *
   485  *  Internally, Windows Phone sends back button events as parameters to
   486  *  special back-button-press callback functions.  Apps that need to respond
   487  *  to back-button-press events are expected to register one or more
   488  *  callback functions for such, shortly after being launched (during the
   489  *  app's initialization phase).  After the back button is pressed, the OS
   490  *  will invoke these callbacks.  If the app's callback(s) do not explicitly
   491  *  mark the event as handled by the time they return, or if the app never
   492  *  registers one of these callback, the OS will consider the event
   493  *  un-handled, and it will apply its default back button behavior (terminate
   494  *  the app).
   495  *
   496  *  SDL registers its own back-button-press callback with the Windows Phone
   497  *  OS.  This callback will emit a pair of SDL key-press events (SDL_KEYDOWN
   498  *  and SDL_KEYUP), each with a scancode of SDL_SCANCODE_AC_BACK, after which
   499  *  it will check the contents of the hint, SDL_HINT_WINRT_HANDLE_BACK_BUTTON.
   500  *  If the hint's value is set to "1", the back button event's Handled
   501  *  property will get set to 'true'.  If the hint's value is set to something
   502  *  else, or if it is unset, SDL will leave the event's Handled property
   503  *  alone.  (By default, the OS sets this property to 'false', to note.)
   504  *
   505  *  SDL apps can either set SDL_HINT_WINRT_HANDLE_BACK_BUTTON well before a
   506  *  back button is pressed, or can set it in direct-response to a back button
   507  *  being pressed.
   508  *
   509  *  In order to get notified when a back button is pressed, SDL apps should
   510  *  register a callback function with SDL_AddEventWatch(), and have it listen
   511  *  for SDL_KEYDOWN events that have a scancode of SDL_SCANCODE_AC_BACK.
   512  *  (Alternatively, SDL_KEYUP events can be listened-for.  Listening for
   513  *  either event type is suitable.)  Any value of SDL_HINT_WINRT_HANDLE_BACK_BUTTON
   514  *  set by such a callback, will be applied to the OS' current
   515  *  back-button-press event.
   516  *
   517  *  More details on back button behavior in Windows Phone apps can be found
   518  *  at the following page, on Microsoft's developer site:
   519  *  http://msdn.microsoft.com/en-us/library/windowsphone/develop/jj247550(v=vs.105).aspx
   520  */
   521 #define SDL_HINT_WINRT_HANDLE_BACK_BUTTON "SDL_WINRT_HANDLE_BACK_BUTTON"
   522 
   523 /**
   524  *  \brief  A variable that dictates policy for fullscreen Spaces on Mac OS X.
   525  *
   526  *  This hint only applies to Mac OS X.
   527  *
   528  *  The variable can be set to the following values:
   529  *    "0"       - Disable Spaces support (FULLSCREEN_DESKTOP won't use them and
   530  *                SDL_WINDOW_RESIZABLE windows won't offer the "fullscreen"
   531  *                button on their titlebars).
   532  *    "1"       - Enable Spaces support (FULLSCREEN_DESKTOP will use them and
   533  *                SDL_WINDOW_RESIZABLE windows will offer the "fullscreen"
   534  *                button on their titlebars).
   535  *
   536  *  The default value is "1". Spaces are disabled regardless of this hint if
   537  *   the OS isn't at least Mac OS X Lion (10.7). This hint must be set before
   538  *   any windows are created.
   539  */
   540 #define SDL_HINT_VIDEO_MAC_FULLSCREEN_SPACES    "SDL_VIDEO_MAC_FULLSCREEN_SPACES"
   541 
   542 /**
   543 *  \brief  When set don't force the SDL app to become a foreground process
   544 *
   545 *  This hint only applies to Mac OS X.
   546 *
   547 */
   548 #define SDL_HINT_MAC_BACKGROUND_APP    "SDL_MAC_BACKGROUND_APP"
   549 
   550 /**
   551  *  \brief Allow mouse click events when clicking to focus an SDL window
   552  *
   553  *  This hint only applies to Mac OS X.
   554  */
   555 #define SDL_HINT_MAC_MOUSE_FOCUS_CLICKTHROUGH "SDL_MAC_MOUSE_FOCUS_CLICKTHROUGH"
   556 
   557 /**
   558  * \brief Android APK expansion main file version. Should be a string number like "1", "2" etc.
   559  *
   560  * Must be set together with SDL_HINT_ANDROID_APK_EXPANSION_PATCH_FILE_VERSION.
   561  *
   562  * If both hints were set then SDL_RWFromFile() will look into expansion files
   563  * after a given relative path was not found in the internal storage and assets.
   564  *
   565  * By default this hint is not set and the APK expansion files are not searched.
   566  */
   567 #define SDL_HINT_ANDROID_APK_EXPANSION_MAIN_FILE_VERSION "SDL_ANDROID_APK_EXPANSION_MAIN_FILE_VERSION"
   568  
   569 /**
   570  * \brief Android APK expansion patch file version. Should be a string number like "1", "2" etc.
   571  *
   572  * Must be set together with SDL_HINT_ANDROID_APK_EXPANSION_MAIN_FILE_VERSION.
   573  *
   574  * If both hints were set then SDL_RWFromFile() will look into expansion files
   575  * after a given relative path was not found in the internal storage and assets.
   576  *
   577  * By default this hint is not set and the APK expansion files are not searched.
   578  */
   579 #define SDL_HINT_ANDROID_APK_EXPANSION_PATCH_FILE_VERSION "SDL_ANDROID_APK_EXPANSION_PATCH_FILE_VERSION"
   580 
   581 /**
   582  * \brief A variable to control whether certain IMEs should handle text editing internally instead of sending SDL_TEXTEDITING events.
   583  *
   584  * The variable can be set to the following values:
   585  *   "0"       - SDL_TEXTEDITING events are sent, and it is the application's
   586  *               responsibility to render the text from these events and 
   587  *               differentiate it somehow from committed text. (default)
   588  *   "1"       - If supported by the IME then SDL_TEXTEDITING events are not sent, 
   589  *               and text that is being composed will be rendered in its own UI.
   590  */
   591 #define SDL_HINT_IME_INTERNAL_EDITING "SDL_IME_INTERNAL_EDITING"
   592 
   593  /**
   594  * \brief A variable to control whether mouse and touch events are to be treated together or separately
   595  *
   596  * The variable can be set to the following values:
   597  *   "0"       - Mouse events will be handled as touch events, and touch will raise fake mouse
   598  *               events. This is the behaviour of SDL <= 2.0.3. (default)
   599  *   "1"       - Mouse events will be handled separately from pure touch events.
   600  *
   601  * The value of this hint is used at runtime, so it can be changed at any time.
   602  */
   603 #define SDL_HINT_ANDROID_SEPARATE_MOUSE_AND_TOUCH "SDL_ANDROID_SEPARATE_MOUSE_AND_TOUCH"
   604 
   605 /**
   606  *  \brief override the binding element for keyboard inputs for Emscripten builds
   607  *
   608  * This hint only applies to the emscripten platform
   609  *
   610  * The variable can be one of
   611  *    "#window"      - The javascript window object (this is the default)
   612  *    "#document"    - The javascript document object
   613  *    "#screen"      - the javascript window.screen object
   614  *    "#canvas"      - the WebGL canvas element
   615  *    any other string without a leading # sign applies to the element on the page with that ID.
   616  */
   617 #define SDL_HINT_EMSCRIPTEN_KEYBOARD_ELEMENT   "SDL_EMSCRIPTEN_KEYBOARD_ELEMENT"
   618 
   619 /**
   620  *  \brief Tell SDL not to catch the SIGINT or SIGTERM signals.
   621  *
   622  * This hint only applies to Unix-like platforms.
   623  *
   624  * The variable can be set to the following values:
   625  *   "0"       - SDL will install a SIGINT and SIGTERM handler, and when it
   626  *               catches a signal, convert it into an SDL_QUIT event.
   627  *   "1"       - SDL will not install a signal handler at all.
   628  */
   629 #define SDL_HINT_NO_SIGNAL_HANDLERS   "SDL_NO_SIGNAL_HANDLERS"
   630 
   631 /**
   632  *  \brief Tell SDL not to generate window-close events for Alt+F4 on Windows.
   633  *
   634  * The variable can be set to the following values:
   635  *   "0"       - SDL will generate a window-close event when it sees Alt+F4.
   636  *   "1"       - SDL will only do normal key handling for Alt+F4.
   637  */
   638 #define SDL_HINT_WINDOWS_NO_CLOSE_ON_ALT_F4	"SDL_WINDOWS_NO_CLOSE_ON_ALT_F4"
   639 
   640 /**
   641  *  \brief  An enumeration of hint priorities
   642  */
   643 typedef enum
   644 {
   645     SDL_HINT_DEFAULT,
   646     SDL_HINT_NORMAL,
   647     SDL_HINT_OVERRIDE
   648 } SDL_HintPriority;
   649 
   650 
   651 /**
   652  *  \brief Set a hint with a specific priority
   653  *
   654  *  The priority controls the behavior when setting a hint that already
   655  *  has a value.  Hints will replace existing hints of their priority and
   656  *  lower.  Environment variables are considered to have override priority.
   657  *
   658  *  \return SDL_TRUE if the hint was set, SDL_FALSE otherwise
   659  */
   660 extern DECLSPEC SDL_bool SDLCALL SDL_SetHintWithPriority(const char *name,
   661                                                          const char *value,
   662                                                          SDL_HintPriority priority);
   663 
   664 /**
   665  *  \brief Set a hint with normal priority
   666  *
   667  *  \return SDL_TRUE if the hint was set, SDL_FALSE otherwise
   668  */
   669 extern DECLSPEC SDL_bool SDLCALL SDL_SetHint(const char *name,
   670                                              const char *value);
   671 
   672 /**
   673  *  \brief Get a hint
   674  *
   675  *  \return The string value of a hint variable.
   676  */
   677 extern DECLSPEC const char * SDLCALL SDL_GetHint(const char *name);
   678 
   679 /**
   680  *  \brief Add a function to watch a particular hint
   681  *
   682  *  \param name The hint to watch
   683  *  \param callback The function to call when the hint value changes
   684  *  \param userdata A pointer to pass to the callback function
   685  */
   686 typedef void (*SDL_HintCallback)(void *userdata, const char *name, const char *oldValue, const char *newValue);
   687 extern DECLSPEC void SDLCALL SDL_AddHintCallback(const char *name,
   688                                                  SDL_HintCallback callback,
   689                                                  void *userdata);
   690 
   691 /**
   692  *  \brief Remove a function watching a particular hint
   693  *
   694  *  \param name The hint being watched
   695  *  \param callback The function being called when the hint value changes
   696  *  \param userdata A pointer being passed to the callback function
   697  */
   698 extern DECLSPEC void SDLCALL SDL_DelHintCallback(const char *name,
   699                                                  SDL_HintCallback callback,
   700                                                  void *userdata);
   701 
   702 /**
   703  *  \brief  Clear all hints
   704  *
   705  *  This function is called during SDL_Quit() to free stored hints.
   706  */
   707 extern DECLSPEC void SDLCALL SDL_ClearHints(void);
   708 
   709 
   710 /* Ends C function definitions when using C++ */
   711 #ifdef __cplusplus
   712 }
   713 #endif
   714 #include "close_code.h"
   715 
   716 #endif /* _SDL_hints_h */
   717 
   718 /* vi: set ts=4 sw=4 expandtab: */