include/SDL_hints.h
author Philipp Wiesemann <philipp.wiesemann@arcor.de>
Thu, 08 Jun 2017 22:40:21 +0200
changeset 11079 08bbd51693d6
parent 11077 8a29b371e2db
child 11182 27ed95cf83d6
permissions -rw-r--r--
Fixed environment variable of SDL_HINT_RENDER_LOGICAL_SIZE_MODE.
     1 /*
     2   Simple DirectMedia Layer
     3   Copyright (C) 1997-2017 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 policy for SDL_RenderSetLogicalSize.
   123  *
   124  *  This variable can be set to the following values:
   125  *    "0" or "letterbox" - Uses letterbox/sidebars to fit the entire rendering on screen
   126  *    "1" or "overscan"  - Will zoom the rendering so it fills the entire screen, allowing edges to be drawn offscreen
   127  *
   128  *  By default letterbox is used
   129  */
   130 #define SDL_HINT_RENDER_LOGICAL_SIZE_MODE       "SDL_RENDER_LOGICAL_SIZE_MODE"
   131 
   132 /**
   133  *  \brief  A variable controlling the scaling quality
   134  *
   135  *  This variable can be set to the following values:
   136  *    "0" or "nearest" - Nearest pixel sampling
   137  *    "1" or "linear"  - Linear filtering (supported by OpenGL and Direct3D)
   138  *    "2" or "best"    - Currently this is the same as "linear"
   139  *
   140  *  By default nearest pixel sampling is used
   141  */
   142 #define SDL_HINT_RENDER_SCALE_QUALITY       "SDL_RENDER_SCALE_QUALITY"
   143 
   144 /**
   145  *  \brief  A variable controlling whether updates to the SDL screen surface should be synchronized with the vertical refresh, to avoid tearing.
   146  *
   147  *  This variable can be set to the following values:
   148  *    "0"       - Disable vsync
   149  *    "1"       - Enable vsync
   150  *
   151  *  By default SDL does not sync screen surface updates with vertical refresh.
   152  */
   153 #define SDL_HINT_RENDER_VSYNC               "SDL_RENDER_VSYNC"
   154 
   155 /**
   156  *  \brief  A variable controlling whether the screensaver is enabled. 
   157  *
   158  *  This variable can be set to the following values:
   159  *    "0"       - Disable screensaver
   160  *    "1"       - Enable screensaver
   161  *
   162  *  By default SDL will disable the screensaver.
   163  */
   164 #define SDL_HINT_VIDEO_ALLOW_SCREENSAVER    "SDL_VIDEO_ALLOW_SCREENSAVER"
   165 
   166 /**
   167  *  \brief  A variable controlling whether the X11 VidMode extension should be used.
   168  *
   169  *  This variable can be set to the following values:
   170  *    "0"       - Disable XVidMode
   171  *    "1"       - Enable XVidMode
   172  *
   173  *  By default SDL will use XVidMode if it is available.
   174  */
   175 #define SDL_HINT_VIDEO_X11_XVIDMODE         "SDL_VIDEO_X11_XVIDMODE"
   176 
   177 /**
   178  *  \brief  A variable controlling whether the X11 Xinerama extension should be used.
   179  *
   180  *  This variable can be set to the following values:
   181  *    "0"       - Disable Xinerama
   182  *    "1"       - Enable Xinerama
   183  *
   184  *  By default SDL will use Xinerama if it is available.
   185  */
   186 #define SDL_HINT_VIDEO_X11_XINERAMA         "SDL_VIDEO_X11_XINERAMA"
   187 
   188 /**
   189  *  \brief  A variable controlling whether the X11 XRandR extension should be used.
   190  *
   191  *  This variable can be set to the following values:
   192  *    "0"       - Disable XRandR
   193  *    "1"       - Enable XRandR
   194  *
   195  *  By default SDL will not use XRandR because of window manager issues.
   196  */
   197 #define SDL_HINT_VIDEO_X11_XRANDR           "SDL_VIDEO_X11_XRANDR"
   198 
   199 /**
   200  *  \brief  A variable controlling whether the X11 _NET_WM_PING protocol should be supported.
   201  *
   202  *  This variable can be set to the following values:
   203  *    "0"       - Disable _NET_WM_PING
   204  *    "1"       - Enable _NET_WM_PING
   205  *
   206  *  By default SDL will use _NET_WM_PING, but for applications that know they
   207  *  will not always be able to respond to ping requests in a timely manner they can
   208  *  turn it off to avoid the window manager thinking the app is hung.
   209  *  The hint is checked in CreateWindow.
   210  */
   211 #define SDL_HINT_VIDEO_X11_NET_WM_PING      "SDL_VIDEO_X11_NET_WM_PING"
   212 
   213 /**
   214  *  \brief  A variable controlling whether the window frame and title bar are interactive when the cursor is hidden 
   215  *
   216  *  This variable can be set to the following values:
   217  *    "0"       - The window frame is not interactive when the cursor is hidden (no move, resize, etc)
   218  *    "1"       - The window frame is interactive when the cursor is hidden
   219  *
   220  *  By default SDL will allow interaction with the window frame when the cursor is hidden
   221  */
   222 #define SDL_HINT_WINDOW_FRAME_USABLE_WHILE_CURSOR_HIDDEN    "SDL_WINDOW_FRAME_USABLE_WHILE_CURSOR_HIDDEN"
   223 
   224 /**
   225  *  \brief  A variable controlling whether the windows message loop is processed by SDL 
   226  *
   227  *  This variable can be set to the following values:
   228  *    "0"       - The window message loop is not run
   229  *    "1"       - The window message loop is processed in SDL_PumpEvents()
   230  *
   231  *  By default SDL will process the windows message loop
   232  */
   233 #define SDL_HINT_WINDOWS_ENABLE_MESSAGELOOP "SDL_WINDOWS_ENABLE_MESSAGELOOP"
   234 
   235 /**
   236  *  \brief  A variable controlling whether grabbing input grabs the keyboard
   237  *
   238  *  This variable can be set to the following values:
   239  *    "0"       - Grab will affect only the mouse
   240  *    "1"       - Grab will affect mouse and keyboard
   241  *
   242  *  By default SDL will not grab the keyboard so system shortcuts still work.
   243  */
   244 #define SDL_HINT_GRAB_KEYBOARD              "SDL_GRAB_KEYBOARD"
   245 
   246 /**
   247  *  \brief  A variable setting the speed scale for mouse motion, in floating point, when the mouse is not in relative mode
   248  */
   249 #define SDL_HINT_MOUSE_NORMAL_SPEED_SCALE    "SDL_MOUSE_NORMAL_SPEED_SCALE"
   250 
   251 /**
   252  *  \brief  A variable setting the scale for mouse motion, in floating point, when the mouse is in relative mode
   253  */
   254 #define SDL_HINT_MOUSE_RELATIVE_SPEED_SCALE    "SDL_MOUSE_RELATIVE_SPEED_SCALE"
   255 
   256 /**
   257  *  \brief  A variable controlling whether relative mouse mode is implemented using mouse warping
   258  *
   259  *  This variable can be set to the following values:
   260  *    "0"       - Relative mouse mode uses raw input
   261  *    "1"       - Relative mouse mode uses mouse warping
   262  *
   263  *  By default SDL will use raw input for relative mouse mode
   264  */
   265 #define SDL_HINT_MOUSE_RELATIVE_MODE_WARP    "SDL_MOUSE_RELATIVE_MODE_WARP"
   266 
   267 /**
   268  *  \brief Allow mouse click events when clicking to focus an SDL window
   269  *
   270  *  This variable can be set to the following values:
   271  *    "0"       - Ignore mouse clicks that activate a window
   272  *    "1"       - Generate events for mouse clicks that activate a window
   273  *
   274  *  By default SDL will ignore mouse clicks that activate a window
   275  */
   276 #define SDL_HINT_MOUSE_FOCUS_CLICKTHROUGH "SDL_MOUSE_FOCUS_CLICKTHROUGH"
   277 
   278 /**
   279  *  \brief Minimize your SDL_Window if it loses key focus when in fullscreen mode. Defaults to true.
   280  *
   281  */
   282 #define SDL_HINT_VIDEO_MINIMIZE_ON_FOCUS_LOSS   "SDL_VIDEO_MINIMIZE_ON_FOCUS_LOSS"
   283 
   284 /**
   285  *  \brief  A variable controlling whether the idle timer is disabled on iOS.
   286  *
   287  *  When an iOS app does not receive touches for some time, the screen is
   288  *  dimmed automatically. For games where the accelerometer is the only input
   289  *  this is problematic. This functionality can be disabled by setting this
   290  *  hint.
   291  *
   292  *  As of SDL 2.0.4, SDL_EnableScreenSaver() and SDL_DisableScreenSaver()
   293  *  accomplish the same thing on iOS. They should be preferred over this hint.
   294  *
   295  *  This variable can be set to the following values:
   296  *    "0"       - Enable idle timer
   297  *    "1"       - Disable idle timer
   298  */
   299 #define SDL_HINT_IDLE_TIMER_DISABLED "SDL_IOS_IDLE_TIMER_DISABLED"
   300 
   301 /**
   302  *  \brief  A variable controlling which orientations are allowed on iOS.
   303  *
   304  *  In some circumstances it is necessary to be able to explicitly control
   305  *  which UI orientations are allowed.
   306  *
   307  *  This variable is a space delimited list of the following values:
   308  *    "LandscapeLeft", "LandscapeRight", "Portrait" "PortraitUpsideDown"
   309  */
   310 #define SDL_HINT_ORIENTATIONS "SDL_IOS_ORIENTATIONS"
   311 
   312 /**
   313  *  \brief  A variable controlling whether controllers used with the Apple TV
   314  *  generate UI events.
   315  *
   316  * When UI events are generated by controller input, the app will be
   317  * backgrounded when the Apple TV remote's menu button is pressed, and when the
   318  * pause or B buttons on gamepads are pressed.
   319  *
   320  * More information about properly making use of controllers for the Apple TV
   321  * can be found here:
   322  * https://developer.apple.com/tvos/human-interface-guidelines/remote-and-controllers/
   323  *
   324  *  This variable can be set to the following values:
   325  *    "0"       - Controller input does not generate UI events (the default).
   326  *    "1"       - Controller input generates UI events.
   327  */
   328 #define SDL_HINT_APPLE_TV_CONTROLLER_UI_EVENTS "SDL_APPLE_TV_CONTROLLER_UI_EVENTS"
   329 
   330 /**
   331  * \brief  A variable controlling whether the Apple TV remote's joystick axes
   332  *         will automatically match the rotation of the remote.
   333  *
   334  *  This variable can be set to the following values:
   335  *    "0"       - Remote orientation does not affect joystick axes (the default).
   336  *    "1"       - Joystick axes are based on the orientation of the remote.
   337  */
   338 #define SDL_HINT_APPLE_TV_REMOTE_ALLOW_ROTATION "SDL_APPLE_TV_REMOTE_ALLOW_ROTATION"
   339 
   340 /**
   341  *  \brief  A variable controlling whether the Android / iOS built-in
   342  *  accelerometer should be listed as a joystick device, rather than listing
   343  *  actual joysticks only.
   344  *
   345  *  This variable can be set to the following values:
   346  *    "0"       - List only real joysticks and accept input from them
   347  *    "1"       - List real joysticks along with the accelerometer as if it were a 3 axis joystick (the default).
   348  */
   349 #define SDL_HINT_ACCELEROMETER_AS_JOYSTICK "SDL_ACCELEROMETER_AS_JOYSTICK"
   350 
   351 
   352 /**
   353  *  \brief  A variable that lets you disable the detection and use of Xinput gamepad devices
   354  *
   355  *  The variable can be set to the following values:
   356  *    "0"       - Disable XInput detection (only uses direct input)
   357  *    "1"       - Enable XInput detection (the default)
   358  */
   359 #define SDL_HINT_XINPUT_ENABLED "SDL_XINPUT_ENABLED"
   360 
   361 
   362 /**
   363  *  \brief  A variable that causes SDL to use the old axis and button mapping for XInput devices.
   364  *
   365  *  This hint is for backwards compatibility only and will be removed in SDL 2.1
   366  *
   367  *  The default value is "0".  This hint must be set before SDL_Init()
   368  */
   369 #define SDL_HINT_XINPUT_USE_OLD_JOYSTICK_MAPPING "SDL_XINPUT_USE_OLD_JOYSTICK_MAPPING"
   370 
   371 
   372 /**
   373  *  \brief  A variable that lets you manually hint extra gamecontroller db entries
   374  *
   375  *  The variable should be newline delimited rows of gamecontroller config data, see SDL_gamecontroller.h
   376  *
   377  *  This hint must be set before calling SDL_Init(SDL_INIT_GAMECONTROLLER)
   378  *  You can update mappings after the system is initialized with SDL_GameControllerMappingForGUID() and SDL_GameControllerAddMapping()
   379  */
   380 #define SDL_HINT_GAMECONTROLLERCONFIG "SDL_GAMECONTROLLERCONFIG"
   381 
   382 
   383 /**
   384  *  \brief  A variable that lets you enable joystick (and gamecontroller) events even when your app is in the background.
   385  *
   386  *  The variable can be set to the following values:
   387  *    "0"       - Disable joystick & gamecontroller input events when the
   388  *                application is in the background.
   389  *    "1"       - Enable joystick & gamecontroller input events when the
   390  *                application is in the background.
   391  *
   392  *  The default value is "0".  This hint may be set at any time.
   393  */
   394 #define SDL_HINT_JOYSTICK_ALLOW_BACKGROUND_EVENTS "SDL_JOYSTICK_ALLOW_BACKGROUND_EVENTS"
   395 
   396 
   397 /**
   398  *  \brief If set to "0" then never set the top most bit on a SDL Window, even if the video mode expects it.
   399  *      This is a debugging aid for developers and not expected to be used by end users. The default is "1"
   400  *
   401  *  This variable can be set to the following values:
   402  *    "0"       - don't allow topmost
   403  *    "1"       - allow topmost
   404  */
   405 #define SDL_HINT_ALLOW_TOPMOST "SDL_ALLOW_TOPMOST"
   406 
   407 
   408 /**
   409  *  \brief A variable that controls the timer resolution, in milliseconds.
   410  *
   411  *  The higher resolution the timer, the more frequently the CPU services
   412  *  timer interrupts, and the more precise delays are, but this takes up
   413  *  power and CPU time.  This hint is only used on Windows 7 and earlier.
   414  *
   415  *  See this blog post for more information:
   416  *  http://randomascii.wordpress.com/2013/07/08/windows-timer-resolution-megawatts-wasted/
   417  *
   418  *  If this variable is set to "0", the system timer resolution is not set.
   419  *
   420  *  The default value is "1". This hint may be set at any time.
   421  */
   422 #define SDL_HINT_TIMER_RESOLUTION "SDL_TIMER_RESOLUTION"
   423 
   424 
   425 /**
   426  *  \brief  A variable describing the content orientation on QtWayland-based platforms.
   427  *
   428  *  On QtWayland platforms, windows are rotated client-side to allow for custom
   429  *  transitions. In order to correctly position overlays (e.g. volume bar) and
   430  *  gestures (e.g. events view, close/minimize gestures), the system needs to
   431  *  know in which orientation the application is currently drawing its contents.
   432  *
   433  *  This does not cause the window to be rotated or resized, the application
   434  *  needs to take care of drawing the content in the right orientation (the
   435  *  framebuffer is always in portrait mode).
   436  *
   437  *  This variable can be one of the following values:
   438  *    "primary" (default), "portrait", "landscape", "inverted-portrait", "inverted-landscape"
   439  */
   440 #define SDL_HINT_QTWAYLAND_CONTENT_ORIENTATION "SDL_QTWAYLAND_CONTENT_ORIENTATION"
   441 
   442 /**
   443  *  \brief  Flags to set on QtWayland windows to integrate with the native window manager.
   444  *
   445  *  On QtWayland platforms, this hint controls the flags to set on the windows.
   446  *  For example, on Sailfish OS "OverridesSystemGestures" disables swipe gestures.
   447  *
   448  *  This variable is a space-separated list of the following values (empty = no flags):
   449  *    "OverridesSystemGestures", "StaysOnTop", "BypassWindowManager"
   450  */
   451 #define SDL_HINT_QTWAYLAND_WINDOW_FLAGS "SDL_QTWAYLAND_WINDOW_FLAGS"
   452 
   453 /**
   454 *  \brief  A string specifying SDL's threads stack size in bytes or "0" for the backend's default size
   455 *
   456 *  Use this hint in case you need to set SDL's threads stack size to other than the default.
   457 *  This is specially useful if you build SDL against a non glibc libc library (such as musl) which
   458 *  provides a relatively small default thread stack size (a few kilobytes versus the default 8MB glibc uses).
   459 *  Support for this hint is currently available only in the pthread, Windows, and PSP backend.
   460 */
   461 #define SDL_HINT_THREAD_STACK_SIZE              "SDL_THREAD_STACK_SIZE"
   462 
   463 /**
   464  *  \brief If set to 1, then do not allow high-DPI windows. ("Retina" on Mac and iOS)
   465  */
   466 #define SDL_HINT_VIDEO_HIGHDPI_DISABLED "SDL_VIDEO_HIGHDPI_DISABLED"
   467 
   468 /**
   469  *  \brief A variable that determines whether ctrl+click should generate a right-click event on Mac
   470  *
   471  *  If present, holding ctrl while left clicking will generate a right click
   472  *  event when on Mac.
   473  */
   474 #define SDL_HINT_MAC_CTRL_CLICK_EMULATE_RIGHT_CLICK "SDL_MAC_CTRL_CLICK_EMULATE_RIGHT_CLICK"
   475 
   476 /**
   477 *  \brief  A variable specifying which shader compiler to preload when using the Chrome ANGLE binaries
   478 *
   479 *  SDL has EGL and OpenGL ES2 support on Windows via the ANGLE project. It
   480 *  can use two different sets of binaries, those compiled by the user from source
   481 *  or those provided by the Chrome browser. In the later case, these binaries require
   482 *  that SDL loads a DLL providing the shader compiler.
   483 *
   484 *  This variable can be set to the following values:
   485 *    "d3dcompiler_46.dll" - default, best for Vista or later.
   486 *    "d3dcompiler_43.dll" - for XP support.
   487 *    "none" - do not load any library, useful if you compiled ANGLE from source and included the compiler in your binaries.
   488 *
   489 */
   490 #define SDL_HINT_VIDEO_WIN_D3DCOMPILER              "SDL_VIDEO_WIN_D3DCOMPILER"
   491 
   492 /**
   493 *  \brief  A variable that is the address of another SDL_Window* (as a hex string formatted with "%p").
   494 *  
   495 *  If this hint is set before SDL_CreateWindowFrom() and the SDL_Window* it is set to has
   496 *  SDL_WINDOW_OPENGL set (and running on WGL only, currently), then two things will occur on the newly 
   497 *  created SDL_Window:
   498 *
   499 *  1. Its pixel format will be set to the same pixel format as this SDL_Window.  This is
   500 *  needed for example when sharing an OpenGL context across multiple windows.
   501 *
   502 *  2. The flag SDL_WINDOW_OPENGL will be set on the new window so it can be used for
   503 *  OpenGL rendering.
   504 *
   505 *  This variable can be set to the following values:
   506 *    The address (as a string "%p") of the SDL_Window* that new windows created with SDL_CreateWindowFrom() should
   507 *    share a pixel format with.
   508 */
   509 #define SDL_HINT_VIDEO_WINDOW_SHARE_PIXEL_FORMAT    "SDL_VIDEO_WINDOW_SHARE_PIXEL_FORMAT"
   510 
   511 /**
   512  *  \brief A URL to a WinRT app's privacy policy
   513  *
   514  *  All network-enabled WinRT apps must make a privacy policy available to its
   515  *  users.  On Windows 8, 8.1, and RT, Microsoft mandates that this policy be
   516  *  be available in the Windows Settings charm, as accessed from within the app.
   517  *  SDL provides code to add a URL-based link there, which can point to the app's
   518  *  privacy policy.
   519  *
   520  *  To setup a URL to an app's privacy policy, set SDL_HINT_WINRT_PRIVACY_POLICY_URL
   521  *  before calling any SDL_Init() functions.  The contents of the hint should
   522  *  be a valid URL.  For example, "http://www.example.com".
   523  *
   524  *  The default value is "", which will prevent SDL from adding a privacy policy
   525  *  link to the Settings charm.  This hint should only be set during app init.
   526  *
   527  *  The label text of an app's "Privacy Policy" link may be customized via another
   528  *  hint, SDL_HINT_WINRT_PRIVACY_POLICY_LABEL.
   529  *
   530  *  Please note that on Windows Phone, Microsoft does not provide standard UI
   531  *  for displaying a privacy policy link, and as such, SDL_HINT_WINRT_PRIVACY_POLICY_URL
   532  *  will not get used on that platform.  Network-enabled phone apps should display
   533  *  their privacy policy through some other, in-app means.
   534  */
   535 #define SDL_HINT_WINRT_PRIVACY_POLICY_URL "SDL_WINRT_PRIVACY_POLICY_URL"
   536 
   537 /** \brief Label text for a WinRT app's privacy policy link
   538  *
   539  *  Network-enabled WinRT apps must include a privacy policy.  On Windows 8, 8.1, and RT,
   540  *  Microsoft mandates that this policy be available via the Windows Settings charm.
   541  *  SDL provides code to add a link there, with its label text being set via the
   542  *  optional hint, SDL_HINT_WINRT_PRIVACY_POLICY_LABEL.
   543  *
   544  *  Please note that a privacy policy's contents are not set via this hint.  A separate
   545  *  hint, SDL_HINT_WINRT_PRIVACY_POLICY_URL, is used to link to the actual text of the
   546  *  policy.
   547  *
   548  *  The contents of this hint should be encoded as a UTF8 string.
   549  *
   550  *  The default value is "Privacy Policy".  This hint should only be set during app
   551  *  initialization, preferably before any calls to SDL_Init().
   552  *
   553  *  For additional information on linking to a privacy policy, see the documentation for
   554  *  SDL_HINT_WINRT_PRIVACY_POLICY_URL.
   555  */
   556 #define SDL_HINT_WINRT_PRIVACY_POLICY_LABEL "SDL_WINRT_PRIVACY_POLICY_LABEL"
   557 
   558 /** \brief Allows back-button-press events on Windows Phone to be marked as handled
   559  *
   560  *  Windows Phone devices typically feature a Back button.  When pressed,
   561  *  the OS will emit back-button-press events, which apps are expected to
   562  *  handle in an appropriate manner.  If apps do not explicitly mark these
   563  *  events as 'Handled', then the OS will invoke its default behavior for
   564  *  unhandled back-button-press events, which on Windows Phone 8 and 8.1 is to
   565  *  terminate the app (and attempt to switch to the previous app, or to the
   566  *  device's home screen).
   567  *
   568  *  Setting the SDL_HINT_WINRT_HANDLE_BACK_BUTTON hint to "1" will cause SDL
   569  *  to mark back-button-press events as Handled, if and when one is sent to
   570  *  the app.
   571  *
   572  *  Internally, Windows Phone sends back button events as parameters to
   573  *  special back-button-press callback functions.  Apps that need to respond
   574  *  to back-button-press events are expected to register one or more
   575  *  callback functions for such, shortly after being launched (during the
   576  *  app's initialization phase).  After the back button is pressed, the OS
   577  *  will invoke these callbacks.  If the app's callback(s) do not explicitly
   578  *  mark the event as handled by the time they return, or if the app never
   579  *  registers one of these callback, the OS will consider the event
   580  *  un-handled, and it will apply its default back button behavior (terminate
   581  *  the app).
   582  *
   583  *  SDL registers its own back-button-press callback with the Windows Phone
   584  *  OS.  This callback will emit a pair of SDL key-press events (SDL_KEYDOWN
   585  *  and SDL_KEYUP), each with a scancode of SDL_SCANCODE_AC_BACK, after which
   586  *  it will check the contents of the hint, SDL_HINT_WINRT_HANDLE_BACK_BUTTON.
   587  *  If the hint's value is set to "1", the back button event's Handled
   588  *  property will get set to 'true'.  If the hint's value is set to something
   589  *  else, or if it is unset, SDL will leave the event's Handled property
   590  *  alone.  (By default, the OS sets this property to 'false', to note.)
   591  *
   592  *  SDL apps can either set SDL_HINT_WINRT_HANDLE_BACK_BUTTON well before a
   593  *  back button is pressed, or can set it in direct-response to a back button
   594  *  being pressed.
   595  *
   596  *  In order to get notified when a back button is pressed, SDL apps should
   597  *  register a callback function with SDL_AddEventWatch(), and have it listen
   598  *  for SDL_KEYDOWN events that have a scancode of SDL_SCANCODE_AC_BACK.
   599  *  (Alternatively, SDL_KEYUP events can be listened-for.  Listening for
   600  *  either event type is suitable.)  Any value of SDL_HINT_WINRT_HANDLE_BACK_BUTTON
   601  *  set by such a callback, will be applied to the OS' current
   602  *  back-button-press event.
   603  *
   604  *  More details on back button behavior in Windows Phone apps can be found
   605  *  at the following page, on Microsoft's developer site:
   606  *  http://msdn.microsoft.com/en-us/library/windowsphone/develop/jj247550(v=vs.105).aspx
   607  */
   608 #define SDL_HINT_WINRT_HANDLE_BACK_BUTTON "SDL_WINRT_HANDLE_BACK_BUTTON"
   609 
   610 /**
   611  *  \brief  A variable that dictates policy for fullscreen Spaces on Mac OS X.
   612  *
   613  *  This hint only applies to Mac OS X.
   614  *
   615  *  The variable can be set to the following values:
   616  *    "0"       - Disable Spaces support (FULLSCREEN_DESKTOP won't use them and
   617  *                SDL_WINDOW_RESIZABLE windows won't offer the "fullscreen"
   618  *                button on their titlebars).
   619  *    "1"       - Enable Spaces support (FULLSCREEN_DESKTOP will use them and
   620  *                SDL_WINDOW_RESIZABLE windows will offer the "fullscreen"
   621  *                button on their titlebars).
   622  *
   623  *  The default value is "1". Spaces are disabled regardless of this hint if
   624  *   the OS isn't at least Mac OS X Lion (10.7). This hint must be set before
   625  *   any windows are created.
   626  */
   627 #define SDL_HINT_VIDEO_MAC_FULLSCREEN_SPACES    "SDL_VIDEO_MAC_FULLSCREEN_SPACES"
   628 
   629 /**
   630 *  \brief  When set don't force the SDL app to become a foreground process
   631 *
   632 *  This hint only applies to Mac OS X.
   633 *
   634 */
   635 #define SDL_HINT_MAC_BACKGROUND_APP    "SDL_MAC_BACKGROUND_APP"
   636 
   637 /**
   638  * \brief Android APK expansion main file version. Should be a string number like "1", "2" etc.
   639  *
   640  * Must be set together with SDL_HINT_ANDROID_APK_EXPANSION_PATCH_FILE_VERSION.
   641  *
   642  * If both hints were set then SDL_RWFromFile() will look into expansion files
   643  * after a given relative path was not found in the internal storage and assets.
   644  *
   645  * By default this hint is not set and the APK expansion files are not searched.
   646  */
   647 #define SDL_HINT_ANDROID_APK_EXPANSION_MAIN_FILE_VERSION "SDL_ANDROID_APK_EXPANSION_MAIN_FILE_VERSION"
   648  
   649 /**
   650  * \brief Android APK expansion patch file version. Should be a string number like "1", "2" etc.
   651  *
   652  * Must be set together with SDL_HINT_ANDROID_APK_EXPANSION_MAIN_FILE_VERSION.
   653  *
   654  * If both hints were set then SDL_RWFromFile() will look into expansion files
   655  * after a given relative path was not found in the internal storage and assets.
   656  *
   657  * By default this hint is not set and the APK expansion files are not searched.
   658  */
   659 #define SDL_HINT_ANDROID_APK_EXPANSION_PATCH_FILE_VERSION "SDL_ANDROID_APK_EXPANSION_PATCH_FILE_VERSION"
   660 
   661 /**
   662  * \brief A variable to control whether certain IMEs should handle text editing internally instead of sending SDL_TEXTEDITING events.
   663  *
   664  * The variable can be set to the following values:
   665  *   "0"       - SDL_TEXTEDITING events are sent, and it is the application's
   666  *               responsibility to render the text from these events and 
   667  *               differentiate it somehow from committed text. (default)
   668  *   "1"       - If supported by the IME then SDL_TEXTEDITING events are not sent, 
   669  *               and text that is being composed will be rendered in its own UI.
   670  */
   671 #define SDL_HINT_IME_INTERNAL_EDITING "SDL_IME_INTERNAL_EDITING"
   672 
   673  /**
   674  * \brief A variable to control whether mouse and touch events are to be treated together or separately
   675  *
   676  * The variable can be set to the following values:
   677  *   "0"       - Mouse events will be handled as touch events, and touch will raise fake mouse
   678  *               events. This is the behaviour of SDL <= 2.0.3. (default)
   679  *   "1"       - Mouse events will be handled separately from pure touch events.
   680  *
   681  * The value of this hint is used at runtime, so it can be changed at any time.
   682  */
   683 #define SDL_HINT_ANDROID_SEPARATE_MOUSE_AND_TOUCH "SDL_ANDROID_SEPARATE_MOUSE_AND_TOUCH"
   684 
   685 /**
   686  *  \brief override the binding element for keyboard inputs for Emscripten builds
   687  *
   688  * This hint only applies to the emscripten platform
   689  *
   690  * The variable can be one of
   691  *    "#window"      - The javascript window object (this is the default)
   692  *    "#document"    - The javascript document object
   693  *    "#screen"      - the javascript window.screen object
   694  *    "#canvas"      - the WebGL canvas element
   695  *    any other string without a leading # sign applies to the element on the page with that ID.
   696  */
   697 #define SDL_HINT_EMSCRIPTEN_KEYBOARD_ELEMENT   "SDL_EMSCRIPTEN_KEYBOARD_ELEMENT"
   698 
   699 /**
   700  *  \brief Tell SDL not to catch the SIGINT or SIGTERM signals.
   701  *
   702  * This hint only applies to Unix-like platforms.
   703  *
   704  * The variable can be set to the following values:
   705  *   "0"       - SDL will install a SIGINT and SIGTERM handler, and when it
   706  *               catches a signal, convert it into an SDL_QUIT event.
   707  *   "1"       - SDL will not install a signal handler at all.
   708  */
   709 #define SDL_HINT_NO_SIGNAL_HANDLERS   "SDL_NO_SIGNAL_HANDLERS"
   710 
   711 /**
   712  *  \brief Tell SDL not to generate window-close events for Alt+F4 on Windows.
   713  *
   714  * The variable can be set to the following values:
   715  *   "0"       - SDL will generate a window-close event when it sees Alt+F4.
   716  *   "1"       - SDL will only do normal key handling for Alt+F4.
   717  */
   718 #define SDL_HINT_WINDOWS_NO_CLOSE_ON_ALT_F4	"SDL_WINDOWS_NO_CLOSE_ON_ALT_F4"
   719 
   720 /**
   721  *  \brief Prevent SDL from using version 4 of the bitmap header when saving BMPs.
   722  *
   723  * The bitmap header version 4 is required for proper alpha channel support and
   724  * SDL will use it when required. Should this not be desired, this hint can
   725  * force the use of the 40 byte header version which is supported everywhere.
   726  *
   727  * The variable can be set to the following values:
   728  *   "0"       - Surfaces with a colorkey or an alpha channel are saved to a
   729  *               32-bit BMP file with an alpha mask. SDL will use the bitmap
   730  *               header version 4 and set the alpha mask accordingly.
   731  *   "1"       - Surfaces with a colorkey or an alpha channel are saved to a
   732  *               32-bit BMP file without an alpha mask. The alpha channel data
   733  *               will be in the file, but applications are going to ignore it.
   734  *
   735  * The default value is "0".
   736  */
   737 #define SDL_HINT_BMP_SAVE_LEGACY_FORMAT "SDL_BMP_SAVE_LEGACY_FORMAT"
   738 
   739 /**
   740  * \brief Tell SDL not to name threads on Windows with the 0x406D1388 Exception.
   741  *        The 0x406D1388 Exception is a trick used to inform Visual Studio of a
   742  *        thread's name, but it tends to cause problems with other debuggers,
   743  *        and the .NET runtime. Note that SDL 2.0.6 and later will still use
   744  *        the (safer) SetThreadDescription API, introduced in the Windows 10
   745  *        Creators Update, if available.
   746  *
   747  * The variable can be set to the following values:
   748  *   "0"       - SDL will raise the 0x406D1388 Exception to name threads.
   749  *               This is the default behavior of SDL <= 2.0.4.
   750  *   "1"       - SDL will not raise this exception, and threads will be unnamed. (default)
   751  *               This is necessary with .NET languages or debuggers that aren't Visual Studio.
   752  */
   753 #define SDL_HINT_WINDOWS_DISABLE_THREAD_NAMING "SDL_WINDOWS_DISABLE_THREAD_NAMING"
   754 
   755 /**
   756  * \brief Tell SDL which Dispmanx layer to use on a Raspberry PI
   757  *
   758  * Also known as Z-order. The variable can take a negative or positive value.
   759  * The default is 10000.
   760  */
   761 #define SDL_HINT_RPI_VIDEO_LAYER           "SDL_RPI_VIDEO_LAYER"
   762 
   763 /**
   764  *  \brief  A variable controlling what driver to use for OpenGL ES contexts.
   765  *
   766  *  On some platforms, currently Windows and X11, OpenGL drivers may support
   767  *  creating contexts with an OpenGL ES profile. By default SDL uses these
   768  *  profiles, when available, otherwise it attempts to load an OpenGL ES
   769  *  library, e.g. that provided by the ANGLE project. This variable controls
   770  *  whether SDL follows this default behaviour or will always load an
   771  *  OpenGL ES library.
   772  *
   773  *  Circumstances where this is useful include
   774  *  - Testing an app with a particular OpenGL ES implementation, e.g ANGLE,
   775  *    or emulator, e.g. those from ARM, Imagination or Qualcomm.
   776  *  - Resolving OpenGL ES function addresses at link time by linking with
   777  *    the OpenGL ES library instead of querying them at run time with
   778  *    SDL_GL_GetProcAddress().
   779  *
   780  *  Caution: for an application to work with the default behaviour across
   781  *  different OpenGL drivers it must query the OpenGL ES function
   782  *  addresses at run time using SDL_GL_GetProcAddress().
   783  *
   784  *  This variable is ignored on most platforms because OpenGL ES is native
   785  *  or not supported.
   786  *
   787  *  This variable can be set to the following values:
   788  *    "0"       - Use ES profile of OpenGL, if available. (Default when not set.)
   789  *    "1"       - Load OpenGL ES library using the default library names.
   790  *
   791  */
   792 #define SDL_HINT_OPENGL_ES_DRIVER   "SDL_OPENGL_ES_DRIVER"
   793 
   794 /**
   795  *  \brief  A variable controlling speed/quality tradeoff of audio resampling.
   796  *
   797  *  If available, SDL can use libsamplerate ( http://www.mega-nerd.com/SRC/ )
   798  *  to handle audio resampling. There are different resampling modes available
   799  *  that produce different levels of quality, using more CPU.
   800  *
   801  *  If this hint isn't specified to a valid setting, or libsamplerate isn't
   802  *  available, SDL will use the default, internal resampling algorithm.
   803  *
   804  *  Note that this is currently only applicable to resampling audio that is
   805  *  being written to a device for playback or audio being read from a device
   806  *  for capture. SDL_AudioCVT always uses the default resampler (although this
   807  *  might change for SDL 2.1).
   808  *
   809  *  This hint is currently only checked at audio subsystem initialization.
   810  *
   811  *  This variable can be set to the following values:
   812  *
   813  *    "0" or "default" - Use SDL's internal resampling (Default when not set - low quality, fast)
   814  *    "1" or "fast"    - Use fast, slightly higher quality resampling, if available
   815  *    "2" or "medium"  - Use medium quality resampling, if available
   816  *    "3" or "best"    - Use high quality resampling, if available
   817  */
   818 #define SDL_HINT_AUDIO_RESAMPLING_MODE   "SDL_AUDIO_RESAMPLING_MODE"
   819 
   820 /**
   821  *  \brief  An enumeration of hint priorities
   822  */
   823 typedef enum
   824 {
   825     SDL_HINT_DEFAULT,
   826     SDL_HINT_NORMAL,
   827     SDL_HINT_OVERRIDE
   828 } SDL_HintPriority;
   829 
   830 
   831 /**
   832  *  \brief Set a hint with a specific priority
   833  *
   834  *  The priority controls the behavior when setting a hint that already
   835  *  has a value.  Hints will replace existing hints of their priority and
   836  *  lower.  Environment variables are considered to have override priority.
   837  *
   838  *  \return SDL_TRUE if the hint was set, SDL_FALSE otherwise
   839  */
   840 extern DECLSPEC SDL_bool SDLCALL SDL_SetHintWithPriority(const char *name,
   841                                                          const char *value,
   842                                                          SDL_HintPriority priority);
   843 
   844 /**
   845  *  \brief Set a hint with normal priority
   846  *
   847  *  \return SDL_TRUE if the hint was set, SDL_FALSE otherwise
   848  */
   849 extern DECLSPEC SDL_bool SDLCALL SDL_SetHint(const char *name,
   850                                              const char *value);
   851 
   852 /**
   853  *  \brief Get a hint
   854  *
   855  *  \return The string value of a hint variable.
   856  */
   857 extern DECLSPEC const char * SDLCALL SDL_GetHint(const char *name);
   858 
   859 /**
   860  *  \brief Get a hint
   861  *
   862  *  \return The boolean value of a hint variable.
   863  */
   864 extern DECLSPEC SDL_bool SDLCALL SDL_GetHintBoolean(const char *name, SDL_bool default_value);
   865 
   866 /**
   867  * \brief type definition of the hint callback function.
   868  */
   869 typedef void (*SDL_HintCallback)(void *userdata, const char *name, const char *oldValue, const char *newValue);
   870 
   871 /**
   872  *  \brief Add a function to watch a particular hint
   873  *
   874  *  \param name The hint to watch
   875  *  \param callback The function to call when the hint value changes
   876  *  \param userdata A pointer to pass to the callback function
   877  */
   878 extern DECLSPEC void SDLCALL SDL_AddHintCallback(const char *name,
   879                                                  SDL_HintCallback callback,
   880                                                  void *userdata);
   881 
   882 /**
   883  *  \brief Remove a function watching a particular hint
   884  *
   885  *  \param name The hint being watched
   886  *  \param callback The function being called when the hint value changes
   887  *  \param userdata A pointer being passed to the callback function
   888  */
   889 extern DECLSPEC void SDLCALL SDL_DelHintCallback(const char *name,
   890                                                  SDL_HintCallback callback,
   891                                                  void *userdata);
   892 
   893 /**
   894  *  \brief  Clear all hints
   895  *
   896  *  This function is called during SDL_Quit() to free stored hints.
   897  */
   898 extern DECLSPEC void SDLCALL SDL_ClearHints(void);
   899 
   900 
   901 /* Ends C function definitions when using C++ */
   902 #ifdef __cplusplus
   903 }
   904 #endif
   905 #include "close_code.h"
   906 
   907 #endif /* SDL_hints_h_ */
   908 
   909 /* vi: set ts=4 sw=4 expandtab: */