include/SDL_video.h
author Sam Lantinga <slouken@libsdl.org>
Wed, 12 Jul 2006 06:39:26 +0000
changeset 1897 c2a27da60b18
parent 1895 c121d94672cb
child 1907 06c27a737b7a
permissions -rw-r--r--
Solved the performance problems by introducing the concept of a single-buffered
display, which is a fast path used for the whole-surface SDL 1.2 API.
Solved the flicker problems by implementing a backbuffer in the GDI renderer.

Unfortunately, now using the GDI renderer with a backbuffer and HBITMAPs is
significantly slower than SDL's surface code. *sigh*
     1 /*
     2     SDL - Simple DirectMedia Layer
     3     Copyright (C) 1997-2006 Sam Lantinga
     4 
     5     This library is free software; you can redistribute it and/or
     6     modify it under the terms of the GNU Lesser General Public
     7     License as published by the Free Software Foundation; either
     8     version 2.1 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     Lesser General Public License for more details.
    14 
    15     You should have received a copy of the GNU Lesser General Public
    16     License along with this library; if not, write to the Free Software
    17     Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
    18 
    19     Sam Lantinga
    20     slouken@libsdl.org
    21 */
    22 
    23 /**
    24  * \file SDL_video.h
    25  *
    26  * Header file for access to the SDL raw framebuffer window
    27  */
    28 
    29 #ifndef _SDL_video_h
    30 #define _SDL_video_h
    31 
    32 #include "SDL_stdinc.h"
    33 #include "SDL_error.h"
    34 #include "SDL_pixels.h"
    35 #include "SDL_rwops.h"
    36 
    37 #include "begin_code.h"
    38 /* Set up for C function definitions, even when using C++ */
    39 #ifdef __cplusplus
    40 /* *INDENT-OFF* */
    41 extern "C" {
    42 /* *INDENT-ON* */
    43 #endif
    44 
    45 /* Transparency definitions: These define alpha as the opacity of a surface */
    46 #define SDL_ALPHA_OPAQUE 255
    47 #define SDL_ALPHA_TRANSPARENT 0
    48 
    49 /**
    50  * \struct SDL_Rect
    51  *
    52  * \brief A rectangle, with the origin at the upper left.
    53  */
    54 typedef struct SDL_Rect
    55 {
    56     int x, y;
    57     int w, h;
    58 } SDL_Rect;
    59 
    60 /**
    61  * \struct SDL_DisplayMode
    62  *
    63  * \brief  The structure that defines a display mode
    64  *
    65  * \sa SDL_GetNumDisplayModes()
    66  * \sa SDL_GetDisplayMode()
    67  * \sa SDL_GetDesktopDisplayMode()
    68  * \sa SDL_GetCurrentDisplayMode()
    69  * \sa SDL_GetClosestDisplayMode()
    70  * \sa SDL_SetDisplayMode()
    71  */
    72 typedef struct
    73 {
    74     Uint32 format;              /**< pixel format */
    75     int w;                      /**< width */
    76     int h;                      /**< height */
    77     int refresh_rate;           /**< refresh rate (or zero for unspecified) */
    78     void *driverdata;           /**< driver-specific data, initialize to 0 */
    79 } SDL_DisplayMode;
    80 
    81 /**
    82  * \typedef SDL_WindowID
    83  *
    84  * \brief The type used to identify a window
    85  *
    86  * \sa SDL_CreateWindow()
    87  * \sa SDL_CreateWindowFrom()
    88  * \sa SDL_DestroyWindow()
    89  * \sa SDL_GetWindowData()
    90  * \sa SDL_GetWindowFlags()
    91  * \sa SDL_GetWindowGrab()
    92  * \sa SDL_GetWindowPosition()
    93  * \sa SDL_GetWindowSize()
    94  * \sa SDL_GetWindowTitle()
    95  * \sa SDL_HideWindow()
    96  * \sa SDL_MaximizeWindow()
    97  * \sa SDL_MinimizeWindow()
    98  * \sa SDL_RaiseWindow()
    99  * \sa SDL_RestoreWindow()
   100  * \sa SDL_SetWindowData()
   101  * \sa SDL_SetWindowFullscreen()
   102  * \sa SDL_SetWindowGrab()
   103  * \sa SDL_SetWindowIcon()
   104  * \sa SDL_SetWindowPosition()
   105  * \sa SDL_SetWindowSize()
   106  * \sa SDL_SetWindowTitle()
   107  * \sa SDL_ShowWindow()
   108  */
   109 typedef Uint32 SDL_WindowID;
   110 
   111 /**
   112  * \enum SDL_WindowFlags
   113  *
   114  * \brief The flags on a window
   115  *
   116  * \sa SDL_GetWindowFlags()
   117  */
   118 typedef enum
   119 {
   120     SDL_WINDOW_FULLSCREEN = 0x00000001,         /**< fullscreen window, implies borderless */
   121     SDL_WINDOW_OPENGL = 0x00000002,             /**< window usable with OpenGL context */
   122     SDL_WINDOW_SHOWN = 0x00000004,              /**< window is visible */
   123     SDL_WINDOW_BORDERLESS = 0x00000008,         /**< no window decoration */
   124     SDL_WINDOW_RESIZABLE = 0x00000010,          /**< window can be resized */
   125     SDL_WINDOW_MINIMIZED = 0x00000020,          /**< minimized */
   126     SDL_WINDOW_MAXIMIZED = 0x00000040,          /**< maximized */
   127     SDL_WINDOW_INPUT_GRABBED = 0x00000100,      /**< window has grabbed input focus */
   128     SDL_WINDOW_INPUT_FOCUS = 0x00000200,        /**< window has input focus */
   129     SDL_WINDOW_MOUSE_FOCUS = 0x00000400,        /**< window has mouse focus */
   130 } SDL_WindowFlags;
   131 
   132 /**
   133  * \def SDL_WINDOWPOS_UNDEFINED
   134  * \brief Used to indicate that you don't care what the window position is.
   135  */
   136 #define SDL_WINDOWPOS_UNDEFINED 0x7FFFFFF
   137 /**
   138  * \def SDL_WINDOWPOS_CENTERED
   139  * \brief Used to indicate that the window position should be centered.
   140  */
   141 #define SDL_WINDOWPOS_CENTERED  0x7FFFFFE
   142 
   143 /**
   144  * \enum SDL_WindowEventID
   145  *
   146  * \brief Event subtype for window events
   147  */
   148 typedef enum
   149 {
   150     SDL_WINDOWEVENT_NONE,               /**< Never used */
   151     SDL_WINDOWEVENT_SHOWN,              /**< Window has been shown */
   152     SDL_WINDOWEVENT_HIDDEN,             /**< Window has been hidden */
   153     SDL_WINDOWEVENT_EXPOSED,            /**< Window has been exposed and should be redrawn */
   154     SDL_WINDOWEVENT_MOVED,              /**< Window has been moved to data1,data2 */
   155     SDL_WINDOWEVENT_RESIZED,            /**< Window size changed to data1xdata2 */
   156     SDL_WINDOWEVENT_MINIMIZED,          /**< Window has been minimized */
   157     SDL_WINDOWEVENT_MAXIMIZED,          /**< Window has been maximized */
   158     SDL_WINDOWEVENT_RESTORED,           /**< Window has been restored to normal size and position */
   159     SDL_WINDOWEVENT_ENTER,              /**< The window has gained mouse focus */
   160     SDL_WINDOWEVENT_LEAVE,              /**< The window has lost mouse focus */
   161     SDL_WINDOWEVENT_FOCUS_GAINED,       /**< The window has gained keyboard focus */
   162     SDL_WINDOWEVENT_FOCUS_LOST,         /**< The window has lost keyboard focus */
   163     SDL_WINDOWEVENT_CLOSE,                              /**< The window manager requests that the window be closed */
   164 } SDL_WindowEventID;
   165 
   166 /**
   167  * \enum SDL_RendererFlags
   168  *
   169  * \brief Flags used when initializing a render manager.
   170  */
   171 typedef enum
   172 {
   173     SDL_Renderer_SingleBuffer = 0x00000001,     /**< Render directly to the window, if possible */
   174     SDL_Renderer_PresentCopy = 0x00000002,      /**< Present uses a copy from back buffer to the front buffer */
   175     SDL_Renderer_PresentFlip2 = 0x00000004,     /**< Present uses a flip, swapping back buffer and front buffer */
   176     SDL_Renderer_PresentFlip3 = 0x00000008,     /**< Present uses a flip, rotating between two back buffers and a front buffer */
   177     SDL_Renderer_PresentDiscard = 0x00000010,   /**< Present leaves the contents of the backbuffer undefined */
   178     SDL_Renderer_PresentVSync = 0x00000020,     /**< Present is synchronized with the refresh rate */
   179     SDL_Renderer_RenderTarget = 0x00000040,     /**< The renderer can create texture render targets */
   180     SDL_Renderer_Accelerated = 0x00000080,      /**< The renderer uses hardware acceleration */
   181     SDL_Renderer_Minimal = 0x00000100,          /**< The renderer only supports the read/write pixel and present functions */
   182 } SDL_RendererFlags;
   183 
   184 /**
   185  * \struct SDL_RendererInfo
   186  *
   187  * \brief Information on the capabilities of a render manager.
   188  */
   189 typedef struct SDL_RendererInfo
   190 {
   191     const char *name;           /**< The name of the renderer */
   192     Uint32 flags;               /**< Supported SDL_RendererFlags */
   193     Uint32 blend_modes;         /**< A mask of supported blend modes */
   194     Uint32 scale_modes;         /**< A mask of supported scale modes */
   195     Uint32 num_texture_formats; /**< The number of available texture formats */
   196     Uint32 texture_formats[32]; /**< The available texture formats */
   197     int max_texture_width;      /**< The maximimum texture width */
   198     int max_texture_height;     /**< The maximimum texture height */
   199 } SDL_RendererInfo;
   200 
   201 /**
   202  * \enum SDL_TextureAccess
   203  *
   204  * \brief The access pattern allowed for a texture
   205  */
   206 typedef enum
   207 {
   208     SDL_TextureAccess_Render,   /**< Unlockable video memory, rendering allowed */
   209     SDL_TextureAccess_Remote,   /**< Unlockable video memory */
   210     SDL_TextureAccess_Local,    /**< Lockable system memory */
   211 } SDL_TextureAccess;
   212 
   213 /**
   214  * \enum SDL_TextureBlendMode
   215  *
   216  * \brief The blend mode used in SDL_RenderCopy()
   217  */
   218 typedef enum
   219 {
   220     SDL_TextureBlendMode_None = 0x00000000,     /**< No blending */
   221     SDL_TextureBlendMode_Mask = 0x00000001,     /**< dst = A ? src : dst (alpha is mask) */
   222     SDL_TextureBlendMode_Blend = 0x00000002,    /**< dst = (src * A) + (dst * (1-A)) */
   223     SDL_TextureBlendMode_Add = 0x00000004,      /**< dst = (src * A) + dst */
   224     SDL_TextureBlendMode_Mod = 0x00000008,      /**< dst = src * dst */
   225 } SDL_TextureBlendMode;
   226 
   227 /**
   228  * \enum SDL_TextureScaleMode
   229  *
   230  * \brief The scale mode used in SDL_RenderCopy()
   231  */
   232 typedef enum
   233 {
   234     SDL_TextureScaleMode_None = 0x00000000,     /**< No scaling, rectangles must match dimensions */
   235     SDL_TextureScaleMode_Fast = 0x00000001,     /**< Point sampling or equivalent algorithm */
   236     SDL_TextureScaleMode_Slow = 0x00000002,     /**< Linear filtering or equivalent algorithm */
   237     SDL_TextureScaleMode_Best = 0x00000004,     /**< Bicubic filtering or equivalent algorithm */
   238 } SDL_TextureScaleMode;
   239 
   240 /**
   241  * \typedef SDL_TextureID
   242  *
   243  * \brief An efficient driver-specific representation of pixel data
   244  */
   245 typedef Uint32 SDL_TextureID;
   246 
   247 /**
   248  * \typedef SDL_GLContext
   249  *
   250  * \brief An opaque handle to an OpenGL context.
   251  */
   252 typedef void *SDL_GLContext;
   253 
   254 
   255 /* These are the currently supported flags for the SDL_surface */
   256 /* Used internally (read-only) */
   257 #define SDL_HWSURFACE       0x00000001  /* Surface represents a texture */
   258 #define SDL_PREALLOC        0x00000002  /* Surface uses preallocated memory */
   259 #define SDL_SRCALPHA        0x00000004  /* Blit uses source alpha blending */
   260 #define SDL_SRCCOLORKEY     0x00000008  /* Blit uses a source color key */
   261 #define SDL_RLEACCELOK      0x00000010  /* Private flag */
   262 #define SDL_RLEACCEL        0x00000020  /* Surface is RLE encoded */
   263 
   264 /* Evaluates to true if the surface needs to be locked before access */
   265 #define SDL_MUSTLOCK(S)	(((S)->flags & (SDL_HWSURFACE|SDL_RLEACCEL)) != 0)
   266 
   267 /* This structure should be treated as read-only, except for 'pixels',
   268    which, if not NULL, contains the raw pixel data for the surface.
   269 */
   270 typedef struct SDL_Surface
   271 {
   272     Uint32 flags;               /* Read-only */
   273     SDL_PixelFormat *format;    /* Read-only */
   274     int w, h;                   /* Read-only */
   275     int pitch;                  /* Read-only */
   276     void *pixels;               /* Read-write */
   277 
   278     /* texture associated with the surface, if any */
   279     SDL_TextureID textureID;
   280 
   281     /* information needed for surfaces requiring locks */
   282     int locked;
   283     void *lock_data;
   284 
   285     /* clipping information */
   286     SDL_Rect clip_rect;         /* Read-only */
   287 
   288     /* info for fast blit mapping to other surfaces */
   289     struct SDL_BlitMap *map;    /* Private */
   290 
   291     /* format version, bumped at every change to invalidate blit maps */
   292     unsigned int format_version;        /* Private */
   293 
   294     /* Reference count -- used when freeing surface */
   295     int refcount;               /* Read-mostly */
   296 } SDL_Surface;
   297 
   298 /* typedef for private surface blitting functions */
   299 typedef int (*SDL_blit) (struct SDL_Surface * src, SDL_Rect * srcrect,
   300                          struct SDL_Surface * dst, SDL_Rect * dstrect);
   301 
   302 
   303 /**
   304  * \enum SDL_GLattr
   305  *
   306  * \brief OpenGL configuration attributes
   307  */
   308 typedef enum
   309 {
   310     SDL_GL_RED_SIZE,
   311     SDL_GL_GREEN_SIZE,
   312     SDL_GL_BLUE_SIZE,
   313     SDL_GL_ALPHA_SIZE,
   314     SDL_GL_BUFFER_SIZE,
   315     SDL_GL_DOUBLEBUFFER,
   316     SDL_GL_DEPTH_SIZE,
   317     SDL_GL_STENCIL_SIZE,
   318     SDL_GL_ACCUM_RED_SIZE,
   319     SDL_GL_ACCUM_GREEN_SIZE,
   320     SDL_GL_ACCUM_BLUE_SIZE,
   321     SDL_GL_ACCUM_ALPHA_SIZE,
   322     SDL_GL_STEREO,
   323     SDL_GL_MULTISAMPLEBUFFERS,
   324     SDL_GL_MULTISAMPLESAMPLES,
   325     SDL_GL_ACCELERATED_VISUAL
   326 } SDL_GLattr;
   327 
   328 
   329 /* Function prototypes */
   330 
   331 /**
   332  * \fn int SDL_GetNumVideoDrivers(void)
   333  *
   334  * \brief Get the number of video drivers compiled into SDL
   335  *
   336  * \sa SDL_GetVideoDriver()
   337  */
   338 extern DECLSPEC int SDLCALL SDL_GetNumVideoDrivers(void);
   339 
   340 /**
   341  * \fn const char *SDL_GetVideoDriver(int index)
   342  *
   343  * \brief Get the name of a built in video driver.
   344  *
   345  * \note The video drivers are presented in the order in which they are
   346  * normally checked during initialization.
   347  *
   348  * \sa SDL_GetNumVideoDrivers()
   349  */
   350 extern DECLSPEC const char *SDLCALL SDL_GetVideoDriver(int index);
   351 
   352 /**
   353  * \fn int SDL_VideoInit(const char *driver_name, Uint32 flags)
   354  *
   355  * \brief Initialize the video subsystem, optionally specifying a video driver.
   356  *
   357  * \param driver_name Initialize a specific driver by name, or NULL for the default video driver.
   358  * \param flags FIXME: Still needed?
   359  *
   360  * \return 0 on success, -1 on error
   361  *
   362  * This function initializes the video subsystem; setting up a connection
   363  * to the window manager, etc, and determines the available display modes
   364  * and pixel formats, but does not initialize a window or graphics mode.
   365  *
   366  * \sa SDL_VideoQuit()
   367  */
   368 extern DECLSPEC int SDLCALL SDL_VideoInit(const char *driver_name,
   369                                           Uint32 flags);
   370 
   371 /**
   372  * \fn void SDL_VideoQuit(void)
   373  *
   374  * \brief Shuts down the video subsystem.
   375  *
   376  * This function closes all windows, and restores the original video mode.
   377  *
   378  * \sa SDL_VideoInit()
   379  */
   380 extern DECLSPEC void SDLCALL SDL_VideoQuit(void);
   381 
   382 /**
   383  * \fn const char *SDL_GetCurrentVideoDriver(void)
   384  *
   385  * \brief Returns the name of the currently initialized video driver.
   386  *
   387  * \return The name of the current video driver or NULL if no driver
   388  *         has been initialized
   389  *
   390  * \sa SDL_GetNumVideoDrivers()
   391  * \sa SDL_GetVideoDriver()
   392  */
   393 extern DECLSPEC const char *SDLCALL SDL_GetCurrentVideoDriver(void);
   394 
   395 /**
   396  * \fn int SDL_GetNumVideoDisplays(void)
   397  *
   398  * \brief Returns the number of available video displays.
   399  *
   400  * \sa SDL_SelectVideoDisplay()
   401  */
   402 extern DECLSPEC int SDLCALL SDL_GetNumVideoDisplays(void);
   403 
   404 /**
   405  * \fn int SDL_SelectVideoDisplay(int index)
   406  *
   407  * \brief Set the index of the currently selected display.
   408  *
   409  * \return The index of the currently selected display.
   410  *
   411  * \note You can query the currently selected display by passing an index of -1.
   412  *
   413  * \sa SDL_GetNumVideoDisplays()
   414  */
   415 extern DECLSPEC int SDLCALL SDL_SelectVideoDisplay(int index);
   416 
   417 /**
   418  * \fn int SDL_GetNumDisplayModes(void)
   419  *
   420  * \brief Returns the number of available display modes for the current display.
   421  *
   422  * \sa SDL_GetDisplayMode()
   423  */
   424 extern DECLSPEC int SDLCALL SDL_GetNumDisplayModes(void);
   425 
   426 /**
   427  * \fn const SDL_DisplayMode *SDL_GetDisplayMode(int index)
   428  *
   429  * \brief Retrieve information about a specific display mode.
   430  *
   431  * \note The display modes are sorted in this priority:
   432  *       \li bits per pixel -> more colors to fewer colors
   433  *       \li width -> largest to smallest
   434  *       \li height -> largest to smallest
   435  *       \li refresh rate -> highest to lowest
   436  *
   437  * \sa SDL_GetNumDisplayModes()
   438  */
   439 extern DECLSPEC const SDL_DisplayMode *SDLCALL SDL_GetDisplayMode(int index);
   440 
   441 /**
   442  * \fn const SDL_DisplayMode *SDL_GetDesktopDisplayMode(void)
   443  *
   444  * \brief Retrieve information about the desktop display mode for the current display.
   445  */
   446 extern DECLSPEC const SDL_DisplayMode *SDLCALL
   447 SDL_GetDesktopDisplayMode(void);
   448 
   449 /**
   450  * \fn const SDL_DisplayMode *SDL_GetCurrentDisplayMode(void)
   451  *
   452  * \brief Retrieve information about the current display mode.
   453  */
   454 extern DECLSPEC const SDL_DisplayMode *SDLCALL
   455 SDL_GetCurrentDisplayMode(void);
   456 
   457 /**
   458  * \fn SDL_DisplayMode *SDL_GetClosestDisplayMode(const SDL_DisplayMode *mode, SDL_DisplayMode *closest)
   459  *
   460  * \brief Get the closest match to the requested display mode.
   461  *
   462  * \param mode The desired display mode
   463  * \param closest A pointer to a display mode to be filled in with the closest match of the available display modes.
   464  *
   465  * \return The passed in value 'closest', or NULL if no matching video mode was available.
   466  *
   467  * The available display modes are scanned, and 'closest' is filled in with the closest mode matching the requested mode and returned.  The mode format and refresh_rate default to the desktop mode if they are 0.  The modes are scanned with size being first priority, format being second priority, and finally checking the refresh_rate.  If all the available modes are too small, then NULL is returned.
   468  *
   469  * \sa SDL_GetNumDisplayModes()
   470  * \sa SDL_GetDisplayMode()
   471  */
   472 extern DECLSPEC SDL_DisplayMode *SDLCALL SDL_GetClosestDisplayMode(const
   473                                                                    SDL_DisplayMode
   474                                                                    * mode,
   475                                                                    SDL_DisplayMode
   476                                                                    * closest);
   477 
   478 /**
   479  * \fn int SDL_SetFullscreenDisplayMode(const SDL_DisplayMode *mode)
   480  *
   481  * \brief Set the display mode used when a fullscreen window is visible
   482  *        on the currently selected display.
   483  *
   484  * \param mode The mode to use, or NULL for the desktop mode.
   485  *
   486  * \return 0 on success, or -1 if setting the display mode failed.
   487  *
   488  * \sa SDL_SetWindowFullscreen()
   489  */
   490 extern DECLSPEC int SDLCALL SDL_SetFullscreenDisplayMode(const SDL_DisplayMode
   491                                                          * mode);
   492 
   493 /**
   494  * \fn const SDL_DisplayMode *SDL_GetFullscreenDisplayMode(void)
   495  *
   496  * \brief Query the display mode used when a fullscreen window is visible
   497  *        on the currently selected display.
   498  */
   499 extern DECLSPEC const SDL_DisplayMode *SDLCALL
   500 SDL_GetFullscreenDisplayMode(void);
   501 
   502 /**
   503  * \fn int SDL_SetDisplayPalette(const SDL_Color *colors, int firstcolor, int ncolors)
   504  *
   505  * \brief Set the palette entries for indexed display modes.
   506  *
   507  * \return 0 on success, or -1 if the display mode isn't palettized or the colors couldn't be set.
   508  */
   509 extern DECLSPEC int SDLCALL SDL_SetDisplayPalette(const SDL_Color * colors,
   510                                                   int firstcolor,
   511                                                   int ncolors);
   512 
   513 /**
   514  * \fn int SDL_GetDisplayPalette(SDL_Color *colors, int firstcolor, int ncolors)
   515  *
   516  * \brief Gets the palette entries for indexed display modes.
   517  *
   518  * \return 0 on success, or -1 if the display mode isn't palettized
   519  */
   520 extern DECLSPEC int SDLCALL SDL_GetDisplayPalette(SDL_Color * colors,
   521                                                   int firstcolor,
   522                                                   int ncolors);
   523 
   524 /**
   525  * \fn int SDL_SetGamma(float red, float green, float blue)
   526  *
   527  * \brief Set the gamma correction for each of the color channels on the currently selected display.
   528  *
   529  * \return 0 on success, or -1 if setting the gamma isn't supported.
   530  *
   531  * \sa SDL_SetGammaRamp()
   532  */
   533 extern DECLSPEC int SDLCALL SDL_SetGamma(float red, float green, float blue);
   534 
   535 /**
   536  * \fn int SDL_SetGammaRamp(const Uint16 * red, const Uint16 * green, const Uint16 * blue)
   537  *
   538  * \brief Set the gamma ramp for the currently selected display.
   539  *
   540  * \param red The translation table for the red channel, or NULL
   541  * \param green The translation table for the green channel, or NULL
   542  * \param blue The translation table for the blue channel, or NULL
   543  *
   544  * \return 0 on success, or -1 if gamma ramps are unsupported.
   545  *
   546  * Set the gamma translation table for the red, green, and blue channels
   547  * of the video hardware.  Each table is an array of 256 16-bit quantities,
   548  * representing a mapping between the input and output for that channel.
   549  * The input is the index into the array, and the output is the 16-bit
   550  * gamma value at that index, scaled to the output color precision.
   551  * 
   552  * \sa SDL_GetGammaRamp()
   553  */
   554 extern DECLSPEC int SDLCALL SDL_SetGammaRamp(const Uint16 * red,
   555                                              const Uint16 * green,
   556                                              const Uint16 * blue);
   557 
   558 /**
   559  * \fn int SDL_GetGammaRamp(Uint16 * red, Uint16 * green, Uint16 * blue)
   560  *
   561  * \brief Get the gamma ramp for the currently selected display.
   562  *
   563  * \param red A pointer to a 256 element array of 16-bit quantities to hold the translation table for the red channel, or NULL.
   564  * \param green A pointer to a 256 element array of 16-bit quantities to hold the translation table for the green channel, or NULL.
   565  * \param blue A pointer to a 256 element array of 16-bit quantities to hold the translation table for the blue channel, or NULL.
   566  * 
   567  * \return 0 on success, or -1 if gamma ramps are unsupported.
   568  *
   569  * \sa SDL_SetGammaRamp()
   570  */
   571 extern DECLSPEC int SDLCALL SDL_GetGammaRamp(Uint16 * red, Uint16 * green,
   572                                              Uint16 * blue);
   573 
   574 
   575 /**
   576  * \fn SDL_WindowID SDL_CreateWindow(const char *title, int x, int y, int w, int h, Uint32 flags)
   577  *
   578  * \brief Create a window with the specified position, dimensions, and flags.
   579  *
   580  * \param title The title of the window
   581  * \param x The x position of the window
   582  * \param y The y position of the window
   583  * \param w The width of the window
   584  * \param h The height of the window
   585  * \param flags The flags for the window, a mask of any of the following: SDL_WINDOW_FULLSCREEN, SDL_WINDOW_OPENGL, SDL_WINDOW_SHOWN, SDL_WINDOW_BORDERLESS, SDL_WINDOW_RESIZABLE, SDL_WINDOW_MAXIMIZED, SDL_WINDOW_MINIMIZED, SDL_WINDOW_INPUT_GRABBED
   586  *
   587  * \return The id of the window created, or zero if window creation failed.
   588  *
   589  * \note Setting the position to -1, -1, indicates any position is fine.
   590  *
   591  * \sa SDL_DestroyWindow()
   592  */
   593 extern DECLSPEC SDL_WindowID SDLCALL SDL_CreateWindow(const char *title,
   594                                                       int x, int y, int w,
   595                                                       int h, Uint32 flags);
   596 
   597 /**
   598  * \fn SDL_WindowID SDL_CreateWindowFrom(void *data)
   599  *
   600  * \brief Create an SDL window struct from an existing native window.
   601  *
   602  * \param data A pointer to driver-dependent window creation data
   603  *
   604  * \return The id of the window created, or zero if window creation failed.
   605  *
   606  * \warning This function is NOT SUPPORTED, use at your own risk!
   607  *
   608  * \sa SDL_DestroyWindow()
   609  */
   610 extern DECLSPEC SDL_WindowID SDLCALL SDL_CreateWindowFrom(const void *data);
   611 
   612 /**
   613  * \fn Uint32 SDL_GetWindowFlags(SDL_WindowID windowID)
   614  *
   615  * \brief Get the window flags.
   616  */
   617 extern DECLSPEC Uint32 SDLCALL SDL_GetWindowFlags(SDL_WindowID windowID);
   618 
   619 /**
   620  * \fn void SDL_SetWindowTitle(SDL_WindowID windowID, const char *title)
   621  *
   622  * \brief Set the title of the window, in UTF-8 format.
   623  *
   624  * \sa SDL_GetWindowTitle()
   625  */
   626 extern DECLSPEC void SDLCALL SDL_SetWindowTitle(SDL_WindowID windowID,
   627                                                 const char *title);
   628 
   629 /**
   630  * \fn const char *SDL_GetWindowTitle(SDL_WindowID windowID)
   631  *
   632  * \brief Get the title of the window, in UTF-8 format.
   633  *
   634  * \sa SDL_SetWindowTitle()
   635  */
   636 extern DECLSPEC const char *SDLCALL SDL_GetWindowTitle(SDL_WindowID windowID);
   637 
   638 /**
   639  * \fn void SDL_SetWindowIcon(SDL_Surface *icon)
   640  *
   641  * \brief Set the icon of the window.
   642  *
   643  * \param icon The icon for the window
   644  *
   645  * FIXME: The icon needs to be set before the window is first shown.  Should some icon representation be part of the window creation data?
   646  */
   647 extern DECLSPEC void SDLCALL SDL_SetWindowIcon(SDL_Surface * icon);
   648 
   649 /**
   650  * \fn void SDL_SetWindowData(SDL_WindowID windowID, void *userdata)
   651  *
   652  * \brief Associate an arbitrary pointer with the window.
   653  *
   654  * \sa SDL_GetWindowData()
   655  */
   656 extern DECLSPEC void SDLCALL SDL_SetWindowData(SDL_WindowID windowID,
   657                                                void *userdata);
   658 
   659 /**
   660  * \fn void *SDL_GetWindowData(SDL_WindowID windowID)
   661  *
   662  * \brief Retrieve the data pointer associated with the window.
   663  *
   664  * \sa SDL_SetWindowData()
   665  */
   666 extern DECLSPEC void *SDLCALL SDL_GetWindowData(SDL_WindowID windowID);
   667 
   668 /**
   669  * \fn void SDL_SetWindowPosition(SDL_WindowID windowID, int x, int y)
   670  *
   671  * \brief Set the position of the window.
   672  *
   673  * \param windowID The window to reposition
   674  * \param x The x coordinate of the window, SDL_WINDOWPOS_CENTERED, or SDL_WINDOWPOS_UNDEFINED
   675  * \param y The y coordinate of the window, SDL_WINDOWPOS_CENTERED, or SDL_WINDOWPOS_UNDEFINED
   676  *
   677  * \note The window coordinate origin is the upper left of the display.
   678  *
   679  * \sa SDL_GetWindowPosition()
   680  */
   681 extern DECLSPEC void SDLCALL SDL_SetWindowPosition(SDL_WindowID windowID,
   682                                                    int x, int y);
   683 
   684 /**
   685  * \fn void SDL_GetWindowPosition(SDL_WindowID windowID, int *x, int *y)
   686  *
   687  * \brief Get the position of the window.
   688  *
   689  * \sa SDL_SetWindowPosition()
   690  */
   691 extern DECLSPEC void SDLCALL SDL_GetWindowPosition(SDL_WindowID windowID,
   692                                                    int *x, int *y);
   693 
   694 /**
   695  * \fn void SDL_SetWindowSize(SDL_WindowID windowID, int w, int w)
   696  *
   697  * \brief Set the size of the window's client area.
   698  *
   699  * \note You can't change the size of a fullscreen window, it automatically
   700  * matches the size of the display mode.
   701  *
   702  * \sa SDL_GetWindowSize()
   703  */
   704 extern DECLSPEC void SDLCALL SDL_SetWindowSize(SDL_WindowID windowID, int w,
   705                                                int h);
   706 
   707 /**
   708  * \fn void SDL_GetWindowSize(SDL_WindowID windowID, int *w, int *w)
   709  *
   710  * \brief Get the size of the window's client area.
   711  *
   712  * \sa SDL_SetWindowSize()
   713  */
   714 extern DECLSPEC void SDLCALL SDL_GetWindowSize(SDL_WindowID windowID, int *w,
   715                                                int *h);
   716 
   717 /**
   718  * \fn void SDL_ShowWindow(SDL_WindowID windowID)
   719  *
   720  * \brief Show the window
   721  *
   722  * \sa SDL_HideWindow()
   723  */
   724 extern DECLSPEC void SDLCALL SDL_ShowWindow(SDL_WindowID windowID);
   725 
   726 /**
   727  * \fn void SDL_HideWindow(SDL_WindowID windowID)
   728  *
   729  * \brief Hide the window
   730  *
   731  * \sa SDL_ShowWindow()
   732  */
   733 extern DECLSPEC void SDLCALL SDL_HideWindow(SDL_WindowID windowID);
   734 
   735 /**
   736  * \fn void SDL_RaiseWindow(SDL_WindowID windowID)
   737  *
   738  * \brief Raise the window above other windows and set the input focus.
   739  */
   740 extern DECLSPEC void SDLCALL SDL_RaiseWindow(SDL_WindowID windowID);
   741 
   742 /**
   743  * \fn void SDL_MaximizeWindow(SDL_WindowID windowID)
   744  *
   745  * \brief Make the window as large as possible.
   746  *
   747  * \sa SDL_RestoreWindow()
   748  */
   749 extern DECLSPEC void SDLCALL SDL_MaximizeWindow(SDL_WindowID windowID);
   750 
   751 /**
   752  * \fn void SDL_MinimizeWindow(SDL_WindowID windowID)
   753  *
   754  * \brief Minimize the window to an iconic representation.
   755  *
   756  * \sa SDL_RestoreWindow()
   757  */
   758 extern DECLSPEC void SDLCALL SDL_MinimizeWindow(SDL_WindowID windowID);
   759 
   760 /**
   761  * \fn void SDL_RestoreWindow(SDL_WindowID windowID)
   762  *
   763  * \brief Restore the size and position of a minimized or maximized window.
   764  *
   765  * \sa SDL_MaximizeWindow()
   766  * \sa SDL_MinimizeWindow()
   767  */
   768 extern DECLSPEC void SDLCALL SDL_RestoreWindow(SDL_WindowID windowID);
   769 
   770 /**
   771  * \fn int SDL_SetWindowFullscreen(SDL_WindowID windowID, int fullscreen)
   772  *
   773  * \brief Set the window's fullscreen state.
   774  *
   775  * \return 0 on success, or -1 if setting the display mode failed.
   776  *
   777  * \sa SDL_SetFullscreenDisplayMode()
   778  */
   779 extern DECLSPEC int SDLCALL SDL_SetWindowFullscreen(SDL_WindowID windowID,
   780                                                     int fullscreen);
   781 
   782 /**
   783  * \fn void SDL_SetWindowGrab(SDL_WindowID windowID, int mode)
   784  *
   785  * \brief Set the window's input grab mode.
   786  *
   787  * \param mode This is 1 to grab input, and 0 to release input.
   788  *
   789  * \sa SDL_GetWindowGrab()
   790  */
   791 extern DECLSPEC void SDLCALL SDL_SetWindowGrab(SDL_WindowID windowID,
   792                                                int mode);
   793 
   794 /**
   795  * \fn int SDL_GetWindowGrab(SDL_WindowID windowID)
   796  *
   797  * \brief Get the window's input grab mode.
   798  *
   799  * \return This returns 1 if input is grabbed, and 0 otherwise.
   800  *
   801  * \sa SDL_SetWindowGrab()
   802  */
   803 extern DECLSPEC int SDLCALL SDL_GetWindowGrab(SDL_WindowID windowID);
   804 
   805 /**
   806  * \fn SDL_bool SDL_GetWindowWMInfo(SDL_WindowID windowID, struct SDL_SysWMinfo * info)
   807  *
   808  * \brief Get driver specific information about a window.
   809  *
   810  * \note Include SDL_syswm.h for the declaration of SDL_SysWMinfo.
   811  */
   812 struct SDL_SysWMinfo;
   813 extern DECLSPEC SDL_bool SDLCALL SDL_GetWindowWMInfo(SDL_WindowID windowID,
   814                                                      struct SDL_SysWMinfo
   815                                                      *info);
   816 
   817 /**
   818  * \fn void SDL_DestroyWindow(SDL_WindowID windowID)
   819  *
   820  * \brief Destroy a window.
   821  */
   822 extern DECLSPEC void SDLCALL SDL_DestroyWindow(SDL_WindowID windowID);
   823 
   824 /**
   825  * \fn int SDL_GetNumRenderers(void)
   826  *
   827  * \brief Get the number of render managers on the current display.
   828  *
   829  * A render manager is a set of code that handles rendering and texture
   830  * management on a particular display.  Normally there is only one, but
   831  * some drivers may have several available with different capabilities.
   832  *
   833  * \sa SDL_GetRendererInfo()
   834  * \sa SDL_CreateRenderer()
   835  */
   836 extern DECLSPEC int SDLCALL SDL_GetNumRenderers(void);
   837 
   838 /**
   839  * \fn SDL_RendererInfo *SDL_GetRendererInfo(int index)
   840  *
   841  * \brief Get information about a specific render manager on the current
   842  *        display.
   843  *
   844  * \sa SDL_CreateRenderer()
   845  */
   846 extern DECLSPEC int SDLCALL SDL_GetRendererInfo(int index,
   847                                                 SDL_RendererInfo * info);
   848 
   849 /**
   850  * \fn int SDL_CreateRenderer(SDL_WindowID window, int index, Uint32 flags)
   851  *
   852  * \brief Create and make active a 2D rendering context for a window.
   853  *
   854  * \param windowID The window used for rendering
   855  * \param index The index of the render manager to initialize, or -1 to initialize the first one supporting the requested flags.
   856  * \param flags SDL_RendererFlags
   857  *
   858  * \return 0 on success, -1 if the flags were not supported, or -2 if
   859  *         there isn't enough memory to support the requested flags
   860  *
   861  * \sa SDL_SelectRenderer()
   862  * \sa SDL_DestroyRenderer()
   863  */
   864 extern DECLSPEC int SDLCALL SDL_CreateRenderer(SDL_WindowID windowID,
   865                                                int index, Uint32 flags);
   866 
   867 /**
   868  * \fn int SDL_SelectRenderer(SDL_WindowID windowID)
   869  *
   870  * \brief Select the rendering context for a particular window.
   871  *
   872  * \return 0 on success, -1 if the selected window doesn't have a
   873  *         rendering context.
   874  */
   875 extern DECLSPEC int SDLCALL SDL_SelectRenderer(SDL_WindowID windowID);
   876 
   877 /**
   878  * \fn SDL_TextureID SDL_CreateTexture(Uint32 format, int access, int w, int h)
   879  *
   880  * \brief Create a texture for the current rendering context.
   881  *
   882  * \param format The format of the texture
   883  * \param access One of the enumerated values in SDL_TextureAccess
   884  * \param w The width of the texture in pixels
   885  * \param h The height of the texture in pixels
   886  *
   887  * \return The created texture is returned, or 0 if no render manager was active,  the format was unsupported, or the width or height were out of range.
   888  *
   889  * \sa SDL_QueryTexture()
   890  * \sa SDL_DestroyTexture()
   891  */
   892 extern DECLSPEC SDL_TextureID SDLCALL SDL_CreateTexture(Uint32 format,
   893                                                         int access, int w,
   894                                                         int h);
   895 
   896 /**
   897  * \fn SDL_TextureID SDL_CreateTextureFromSurface(Uint32 format, int access, SDL_Surface *surface)
   898  *
   899  * \brief Create a texture from an existing surface.
   900  *
   901  * \param format The format of the texture, or 0 to pick an appropriate format
   902  * \param access One of the enumerated values in SDL_TextureAccess
   903  * \param surface The surface containing pixel data used to fill the texture
   904  *
   905  * \return The created texture is returned, or 0 if no render manager was active,  the format was unsupported, or the surface width or height were out of range.
   906  *
   907  * \note The surface is not modified or freed by this function.
   908  *
   909  * \sa SDL_QueryTexture()
   910  * \sa SDL_DestroyTexture()
   911  */
   912 extern DECLSPEC SDL_TextureID SDLCALL SDL_CreateTextureFromSurface(Uint32
   913                                                                    format,
   914                                                                    int access,
   915                                                                    SDL_Surface
   916                                                                    * surface);
   917 
   918 /**
   919  * \fn int SDL_QueryTexture(SDL_TextureID textureID, Uint32 *format, int *access, int *w, int *h)
   920  *
   921  * \brief Query the attributes of a texture
   922  *
   923  * \param texture A texture to be queried
   924  * \param format A pointer filled in with the raw format of the texture.  The actual format may differ, but pixel transfers will use this format.
   925  * \param access A pointer filled in with the actual access to the texture.
   926  * \param w A pointer filled in with the width of the texture in pixels
   927  * \param h A pointer filled in with the height of the texture in pixels
   928  *
   929  * \return 0 on success, or -1 if the texture is not valid
   930  */
   931 extern DECLSPEC int SDLCALL SDL_QueryTexture(SDL_TextureID textureID,
   932                                              Uint32 * format, int *access,
   933                                              int *w, int *h);
   934 
   935 /**
   936  * \fn int SDL_QueryTexturePixels(SDL_TextureID textureID, void **pixels, int pitch)
   937  *
   938  * \brief Query the pixels of a texture, if the texture does not need to be locked for pixel access.
   939  *
   940  * \param texture A texture to be queried, which was created with SDL_TextureAccess_Local
   941  * \param pixels A pointer filled with a pointer to the pixels for the texture 
   942  * \param pitch A pointer filled in with the pitch of the pixel data
   943  *
   944  * \return 0 on success, or -1 if the texture is not valid, or must be locked for pixel access.
   945  */
   946 extern DECLSPEC int SDLCALL SDL_QueryTexturePixels(SDL_TextureID textureID,
   947                                                    void **pixels, int *pitch);
   948 
   949 /**
   950  * \fn int SDL_SetTexturePalette(SDL_TextureID textureID, const SDL_Color * colors, int firstcolor, int ncolors)
   951  *
   952  * \brief Update an indexed texture with a color palette
   953  *
   954  * \param texture The texture to update
   955  * \param colors The array of RGB color data
   956  * \param firstcolor The first index to update
   957  * \param ncolors The number of palette entries to fill with the color data
   958  *
   959  * \return 0 on success, or -1 if the texture is not valid or not an indexed texture
   960  */
   961 extern DECLSPEC int SDLCALL SDL_SetTexturePalette(SDL_TextureID textureID,
   962                                                   const SDL_Color * colors,
   963                                                   int firstcolor,
   964                                                   int ncolors);
   965 
   966 /**
   967  * \fn int SDL_GetTexturePalette(SDL_TextureID textureID, SDL_Color * colors, int firstcolor, int ncolors)
   968  *
   969  * \brief Update an indexed texture with a color palette
   970  *
   971  * \param texture The texture to update
   972  * \param colors The array to fill with RGB color data
   973  * \param firstcolor The first index to retrieve
   974  * \param ncolors The number of palette entries to retrieve
   975  *
   976  * \return 0 on success, or -1 if the texture is not valid or not an indexed texture
   977  */
   978 extern DECLSPEC int SDLCALL SDL_GetTexturePalette(SDL_TextureID textureID,
   979                                                   SDL_Color * colors,
   980                                                   int firstcolor,
   981                                                   int ncolors);
   982 
   983 /**
   984  * \fn int SDL_UpdateTexture(SDL_TextureID textureID, const SDL_Rect *rect, const void *pixels, int pitch)
   985  *
   986  * \brief Update the given texture rectangle with new pixel data.
   987  *
   988  * \param texture The texture to update
   989  * \param rect A pointer to the rectangle of pixels to update, or NULL to update the entire texture.
   990  * \param pixels The raw pixel data
   991  * \param pitch The number of bytes between rows of pixel data
   992  *
   993  * \return 0 on success, or -1 if the texture is not valid
   994  *
   995  * \note This is a very slow function for textures not created with SDL_TextureAccess_Local.
   996  */
   997 extern DECLSPEC int SDLCALL SDL_UpdateTexture(SDL_TextureID textureID,
   998                                               const SDL_Rect * rect,
   999                                               const void *pixels, int pitch);
  1000 
  1001 /**
  1002  * \fn void SDL_LockTexture(SDL_TextureID textureID, const SDL_Rect *rect, int markDirty, void **pixels, int *pitch)
  1003  *
  1004  * \brief Lock a portion of the texture for pixel access.
  1005  *
  1006  * \param texture The texture to lock for access, which must have been created with SDL_TextureAccess_Local.
  1007  * \param rect A pointer to the rectangle to lock for access. If the rect is NULL, the entire texture will be locked.
  1008  * \param markDirty If this is nonzero, the locked area will be marked dirty when the texture is unlocked.
  1009  * \param pixels This is filled in with a pointer to the locked pixels, appropriately offset by the locked area.
  1010  * \param pitch This is filled in with the pitch of the locked pixels.
  1011  *
  1012  * \return 0 on success, or -1 if the texture is not valid or was created with SDL_TextureAccess_Remote
  1013  *
  1014  * \sa SDL_DirtyTexture()
  1015  * \sa SDL_UnlockTexture()
  1016  */
  1017 extern DECLSPEC int SDLCALL SDL_LockTexture(SDL_TextureID textureID,
  1018                                             const SDL_Rect * rect,
  1019                                             int markDirty, void **pixels,
  1020                                             int *pitch);
  1021 
  1022 /**
  1023  * \fn void SDL_UnlockTexture(SDL_TextureID textureID)
  1024  *
  1025  * \brief Unlock a texture, uploading the changes to video memory, if needed.
  1026  *
  1027  * \sa SDL_LockTexture()
  1028  * \sa SDL_DirtyTexture()
  1029  */
  1030 extern DECLSPEC void SDLCALL SDL_UnlockTexture(SDL_TextureID textureID);
  1031 
  1032 /**
  1033  * \fn void SDL_DirtyTexture(SDL_TextureID textureID, int numrects, const SDL_Rect * rects)
  1034  *
  1035  * \brief Mark the specified rectangles of the texture as dirty.
  1036  *
  1037  * \note The texture must have been created with SDL_TextureAccess_Local.
  1038  *
  1039  * \sa SDL_LockTexture()
  1040  * \sa SDL_UnlockTexture()
  1041  */
  1042 extern DECLSPEC void SDLCALL SDL_DirtyTexture(SDL_TextureID textureID,
  1043                                               int numrects,
  1044                                               const SDL_Rect * rects);
  1045 
  1046 /**
  1047  * \fn void SDL_SelectRenderTexture(SDL_TextureID textureID)
  1048  *
  1049  * \brief Select a texture as the rendering target, or 0 to reselect the current window.
  1050  *
  1051  * \note The texture must have been created with SDL_TextureAccess_Render.
  1052  */
  1053 extern DECLSPEC void SDLCALL SDL_SelectRenderTexture(SDL_TextureID textureID);
  1054 
  1055 /**
  1056  * \fn void SDL_RenderFill(const SDL_Rect *rect, Uint32 color)
  1057  *
  1058  * \brief Fill the current rendering target with the specified color.
  1059  *
  1060  * \param rect A pointer to the destination rectangle, or NULL for the entire rendering target.
  1061  * \param color An ARGB color value.
  1062  *
  1063  * \return 0 on success, or -1 if there is no renderer current
  1064  */
  1065 extern DECLSPEC int SDLCALL SDL_RenderFill(const SDL_Rect * rect,
  1066                                            Uint32 color);
  1067 
  1068 /**
  1069  * \fn int SDL_RenderCopy(SDL_TextureID textureID, const SDL_Rect *srcrect, const SDL_Rect *dstrect, Uint32 blendMode, Uint32 scaleMode)
  1070  *
  1071  * \brief Copy a portion of the texture to the current rendering target.
  1072  *
  1073  * \param texture The source texture.
  1074  * \param srcrect A pointer to the source rectangle, or NULL for the entire texture.
  1075  * \param dstrect A pointer to the destination rectangle, or NULL for the entire rendering target.
  1076  * \param blendMode SDL_TextureBlendMode to be used if the source texture has an alpha channel.
  1077  * \param scaleMode SDL_TextureScaleMode to be used if the source and destination rectangles don't have the same width and height.
  1078  *
  1079  * \return 0 on success, or -1 if there is no renderer current, or the driver doesn't support the requested operation.
  1080  *
  1081  * \note You can check the video driver info to see what operations are supported.
  1082  */
  1083 extern DECLSPEC int SDLCALL SDL_RenderCopy(SDL_TextureID textureID,
  1084                                            const SDL_Rect * srcrect,
  1085                                            const SDL_Rect * dstrect,
  1086                                            int blendMode, int scaleMode);
  1087 
  1088 /**
  1089  * \fn int SDL_RenderReadPixels(const SDL_Rect *rect, void *pixels, int pitch)
  1090  *
  1091  * \brief Read pixels from the current rendering target.
  1092  *
  1093  * \param rect A pointer to the rectangle to read, or NULL for the entire render target
  1094  * \param pixels A pointer to be filled in with the pixel data
  1095  * \param pitch The pitch of the pixels parameter
  1096  *
  1097  * \return 0 on success, or -1 if pixel reading is not supported.
  1098  *
  1099  * \warning This is a very slow operation, and should not be used frequently.
  1100  */
  1101 extern DECLSPEC int SDLCALL SDL_RenderReadPixels(const SDL_Rect * rect,
  1102                                                  void *pixels, int pitch);
  1103 
  1104 /**
  1105  * \fn int SDL_RenderWritePixels(const SDL_Rect *rect, const void *pixels, int pitch)
  1106  *
  1107  * \brief Write pixels to the current rendering target.
  1108  *
  1109  * \param rect A pointer to the rectangle to write, or NULL for the entire render target
  1110  * \param pixels A pointer to the pixel data to write
  1111  * \param pitch The pitch of the pixels parameter
  1112  *
  1113  * \return 0 on success, or -1 if pixel writing is not supported.
  1114  *
  1115  * \warning This is a very slow operation, and should not be used frequently.
  1116  */
  1117 extern DECLSPEC int SDLCALL SDL_RenderWritePixels(const SDL_Rect * rect,
  1118                                                   const void *pixels,
  1119                                                   int pitch);
  1120 
  1121 /**
  1122  * \fn void SDL_RenderPresent(void)
  1123  *
  1124  * \brief Update the screen with rendering performed.
  1125  */
  1126 extern DECLSPEC void SDLCALL SDL_RenderPresent(void);
  1127 
  1128 /**
  1129  * \fn void SDL_DestroyTexture(SDL_TextureID textureID);
  1130  *
  1131  * \brief Destroy the specified texture.
  1132  *
  1133  * \sa SDL_CreateTexture()
  1134  * \sa SDL_CreateTextureFromSurface()
  1135  */
  1136 extern DECLSPEC void SDLCALL SDL_DestroyTexture(SDL_TextureID textureID);
  1137 
  1138 /**
  1139  * \fn void SDL_DestroyRenderer(SDL_WindowID windowID);
  1140  *
  1141  * \brief Destroy the rendering context for a window and free associated
  1142  *        textures.
  1143  *
  1144  * \sa SDL_CreateRenderer()
  1145  */
  1146 extern DECLSPEC void SDLCALL SDL_DestroyRenderer(SDL_WindowID windowID);
  1147 
  1148 /*
  1149  * Maps an RGB triple to an opaque pixel value for a given pixel format
  1150  */
  1151 extern DECLSPEC Uint32 SDLCALL SDL_MapRGB
  1152     (SDL_PixelFormat * format, Uint8 r, Uint8 g, Uint8 b);
  1153 
  1154 /*
  1155  * Maps an RGBA quadruple to a pixel value for a given pixel format
  1156  */
  1157 extern DECLSPEC Uint32 SDLCALL SDL_MapRGBA(SDL_PixelFormat * format,
  1158                                            Uint8 r, Uint8 g, Uint8 b,
  1159                                            Uint8 a);
  1160 
  1161 /*
  1162  * Maps a pixel value into the RGB components for a given pixel format
  1163  */
  1164 extern DECLSPEC void SDLCALL SDL_GetRGB(Uint32 pixel, SDL_PixelFormat * fmt,
  1165                                         Uint8 * r, Uint8 * g, Uint8 * b);
  1166 
  1167 /*
  1168  * Maps a pixel value into the RGBA components for a given pixel format
  1169  */
  1170 extern DECLSPEC void SDLCALL SDL_GetRGBA(Uint32 pixel, SDL_PixelFormat * fmt,
  1171                                          Uint8 * r, Uint8 * g, Uint8 * b,
  1172                                          Uint8 * a);
  1173 
  1174 /*
  1175  * Allocate and free an RGB surface (must be called after SDL_SetVideoMode)
  1176  * If the depth is 4 or 8 bits, an empty palette is allocated for the surface.
  1177  * If the depth is greater than 8 bits, the pixel format is set using the
  1178  * flags '[RGB]mask'.
  1179  * If the function runs out of memory, it will return NULL.
  1180  *
  1181  * The 'flags' tell what kind of surface to create.
  1182  * SDL_SRCCOLORKEY indicates that the surface will be used for colorkey blits.
  1183  * SDL_SRCALPHA means that the surface will be used for alpha blits.
  1184  */
  1185 extern DECLSPEC SDL_Surface *SDLCALL SDL_CreateRGBSurface
  1186     (Uint32 flags, int width, int height, int depth,
  1187      Uint32 Rmask, Uint32 Gmask, Uint32 Bmask, Uint32 Amask);
  1188 extern DECLSPEC SDL_Surface *SDLCALL SDL_CreateRGBSurfaceFrom(void *pixels,
  1189                                                               int width,
  1190                                                               int height,
  1191                                                               int depth,
  1192                                                               int pitch,
  1193                                                               Uint32 Rmask,
  1194                                                               Uint32 Gmask,
  1195                                                               Uint32 Bmask,
  1196                                                               Uint32 Amask);
  1197 extern DECLSPEC SDL_Surface *SDLCALL
  1198 SDL_CreateRGBSurfaceFromTexture(SDL_TextureID textureID);
  1199 extern DECLSPEC void SDLCALL SDL_FreeSurface(SDL_Surface * surface);
  1200 
  1201 /**
  1202  * \fn int SDL_SetSurfacePalette(SDL_Surface *surface, SDL_Palette *palette)
  1203  *
  1204  * \brief Set the palette used by a surface.
  1205  *
  1206  * \return 0, or -1 if the surface format doesn't use a palette.
  1207  *
  1208  * \note A single palette can be shared with many surfaces.
  1209  */
  1210 extern DECLSPEC int SDLCALL SDL_SetSurfacePalette(SDL_Surface * surface,
  1211                                                   SDL_Palette * palette);
  1212 
  1213 /*
  1214  * SDL_LockSurface() sets up a surface for directly accessing the pixels.
  1215  * Between calls to SDL_LockSurface()/SDL_UnlockSurface(), you can write
  1216  * to and read from 'surface->pixels', using the pixel format stored in 
  1217  * 'surface->format'.  Once you are done accessing the surface, you should 
  1218  * use SDL_UnlockSurface() to release it.
  1219  *
  1220  * Not all surfaces require locking.  If SDL_MUSTLOCK(surface) evaluates
  1221  * to 0, then you can read and write to the surface at any time, and the
  1222  * pixel format of the surface will not change.
  1223  * 
  1224  * No operating system or library calls should be made between lock/unlock
  1225  * pairs, as critical system locks may be held during this time.
  1226  *
  1227  * SDL_LockSurface() returns 0, or -1 if the surface couldn't be locked.
  1228  */
  1229 extern DECLSPEC int SDLCALL SDL_LockSurface(SDL_Surface * surface);
  1230 extern DECLSPEC void SDLCALL SDL_UnlockSurface(SDL_Surface * surface);
  1231 
  1232 /*
  1233  * Load a surface from a seekable SDL data source (memory or file.)
  1234  * If 'freesrc' is non-zero, the source will be closed after being read.
  1235  * Returns the new surface, or NULL if there was an error.
  1236  * The new surface should be freed with SDL_FreeSurface().
  1237  */
  1238 extern DECLSPEC SDL_Surface *SDLCALL SDL_LoadBMP_RW(SDL_RWops * src,
  1239                                                     int freesrc);
  1240 
  1241 /* Convenience macro -- load a surface from a file */
  1242 #define SDL_LoadBMP(file)	SDL_LoadBMP_RW(SDL_RWFromFile(file, "rb"), 1)
  1243 
  1244 /*
  1245  * Save a surface to a seekable SDL data source (memory or file.)
  1246  * If 'freedst' is non-zero, the source will be closed after being written.
  1247  * Returns 0 if successful or -1 if there was an error.
  1248  */
  1249 extern DECLSPEC int SDLCALL SDL_SaveBMP_RW
  1250     (SDL_Surface * surface, SDL_RWops * dst, int freedst);
  1251 
  1252 /* Convenience macro -- save a surface to a file */
  1253 #define SDL_SaveBMP(surface, file) \
  1254 		SDL_SaveBMP_RW(surface, SDL_RWFromFile(file, "wb"), 1)
  1255 
  1256 /*
  1257  * Sets the color key (transparent pixel) in a blittable surface.
  1258  * If 'flag' is SDL_SRCCOLORKEY (optionally OR'd with SDL_RLEACCEL), 
  1259  * 'key' will be the transparent pixel in the source image of a blit.
  1260  * SDL_RLEACCEL requests RLE acceleration for the surface if present,
  1261  * and removes RLE acceleration if absent.
  1262  * If 'flag' is 0, this function clears any current color key.
  1263  * This function returns 0, or -1 if there was an error.
  1264  */
  1265 extern DECLSPEC int SDLCALL SDL_SetColorKey
  1266     (SDL_Surface * surface, Uint32 flag, Uint32 key);
  1267 
  1268 /*
  1269  * This function sets the alpha value for the entire surface, as opposed to
  1270  * using the alpha component of each pixel. This value measures the range
  1271  * of transparency of the surface, 0 being completely transparent to 255
  1272  * being completely opaque. An 'alpha' value of 255 causes blits to be
  1273  * opaque, the source pixels copied to the destination (the default). Note
  1274  * that per-surface alpha can be combined with colorkey transparency.
  1275  *
  1276  * If 'flag' is 0, alpha blending is disabled for the surface.
  1277  * If 'flag' is SDL_SRCALPHA, alpha blending is enabled for the surface.
  1278  * OR:ing the flag with SDL_RLEACCEL requests RLE acceleration for the
  1279  * surface; if SDL_RLEACCEL is not specified, the RLE accel will be removed.
  1280  *
  1281  * The 'alpha' parameter is ignored for surfaces that have an alpha channel.
  1282  */
  1283 extern DECLSPEC int SDLCALL SDL_SetAlpha(SDL_Surface * surface, Uint32 flag,
  1284                                          Uint8 alpha);
  1285 
  1286 /*
  1287  * Sets the clipping rectangle for the destination surface in a blit.
  1288  *
  1289  * If the clip rectangle is NULL, clipping will be disabled.
  1290  * If the clip rectangle doesn't intersect the surface, the function will
  1291  * return SDL_FALSE and blits will be completely clipped.  Otherwise the
  1292  * function returns SDL_TRUE and blits to the surface will be clipped to
  1293  * the intersection of the surface area and the clipping rectangle.
  1294  *
  1295  * Note that blits are automatically clipped to the edges of the source
  1296  * and destination surfaces.
  1297  */
  1298 extern DECLSPEC SDL_bool SDLCALL SDL_SetClipRect(SDL_Surface * surface,
  1299                                                  const SDL_Rect * rect);
  1300 
  1301 /*
  1302  * Gets the clipping rectangle for the destination surface in a blit.
  1303  * 'rect' must be a pointer to a valid rectangle which will be filled
  1304  * with the correct values.
  1305  */
  1306 extern DECLSPEC void SDLCALL SDL_GetClipRect(SDL_Surface * surface,
  1307                                              SDL_Rect * rect);
  1308 
  1309 /*
  1310  * Creates a new surface of the specified format, and then copies and maps 
  1311  * the given surface to it so the blit of the converted surface will be as 
  1312  * fast as possible.  If this function fails, it returns NULL.
  1313  *
  1314  * The 'flags' parameter is passed to SDL_CreateRGBSurface() and has those 
  1315  * semantics.  You can also pass SDL_RLEACCEL in the flags parameter and
  1316  * SDL will try to RLE accelerate colorkey and alpha blits in the resulting
  1317  * surface.
  1318  *
  1319  * This function is used internally by SDL_DisplayFormat().
  1320  */
  1321 extern DECLSPEC SDL_Surface *SDLCALL SDL_ConvertSurface
  1322     (SDL_Surface * src, SDL_PixelFormat * fmt, Uint32 flags);
  1323 
  1324 /*
  1325  * This function performs a fast fill of the given rectangle with 'color'
  1326  * The given rectangle is clipped to the destination surface clip area
  1327  * and the final fill rectangle is saved in the passed in pointer.
  1328  * If 'dstrect' is NULL, the whole surface will be filled with 'color'
  1329  * The color should be a pixel of the format used by the surface, and 
  1330  * can be generated by the SDL_MapRGB() function.
  1331  * This function returns 0 on success, or -1 on error.
  1332  */
  1333 extern DECLSPEC int SDLCALL SDL_FillRect
  1334     (SDL_Surface * dst, SDL_Rect * dstrect, Uint32 color);
  1335 
  1336 /*
  1337  * This performs a fast blit from the source surface to the destination
  1338  * surface.  It assumes that the source and destination rectangles are
  1339  * the same size.  If either 'srcrect' or 'dstrect' are NULL, the entire
  1340  * surface (src or dst) is copied.  The final blit rectangles are saved
  1341  * in 'srcrect' and 'dstrect' after all clipping is performed.
  1342  * If the blit is successful, it returns 0, otherwise it returns -1.
  1343  *
  1344  * The blit function should not be called on a locked surface.
  1345  *
  1346  * The blit semantics for surfaces with and without alpha and colorkey
  1347  * are defined as follows:
  1348  *
  1349  * RGBA->RGB:
  1350  *     SDL_SRCALPHA set:
  1351  * 	alpha-blend (using alpha-channel).
  1352  * 	SDL_SRCCOLORKEY ignored.
  1353  *     SDL_SRCALPHA not set:
  1354  * 	copy RGB.
  1355  * 	if SDL_SRCCOLORKEY set, only copy the pixels matching the
  1356  * 	RGB values of the source colour key, ignoring alpha in the
  1357  * 	comparison.
  1358  * 
  1359  * RGB->RGBA:
  1360  *     SDL_SRCALPHA set:
  1361  * 	alpha-blend (using the source per-surface alpha value);
  1362  * 	set destination alpha to opaque.
  1363  *     SDL_SRCALPHA not set:
  1364  * 	copy RGB, set destination alpha to source per-surface alpha value.
  1365  *     both:
  1366  * 	if SDL_SRCCOLORKEY set, only copy the pixels matching the
  1367  * 	source colour key.
  1368  * 
  1369  * RGBA->RGBA:
  1370  *     SDL_SRCALPHA set:
  1371  * 	alpha-blend (using the source alpha channel) the RGB values;
  1372  * 	leave destination alpha untouched. [Note: is this correct?]
  1373  * 	SDL_SRCCOLORKEY ignored.
  1374  *     SDL_SRCALPHA not set:
  1375  * 	copy all of RGBA to the destination.
  1376  * 	if SDL_SRCCOLORKEY set, only copy the pixels matching the
  1377  * 	RGB values of the source colour key, ignoring alpha in the
  1378  * 	comparison.
  1379  * 
  1380  * RGB->RGB: 
  1381  *     SDL_SRCALPHA set:
  1382  * 	alpha-blend (using the source per-surface alpha value).
  1383  *     SDL_SRCALPHA not set:
  1384  * 	copy RGB.
  1385  *     both:
  1386  * 	if SDL_SRCCOLORKEY set, only copy the pixels matching the
  1387  * 	source colour key.
  1388  *
  1389  * If either of the surfaces were in video memory, and the blit returns -2,
  1390  * the video memory was lost, so it should be reloaded with artwork and 
  1391  * re-blitted:
  1392 	while ( SDL_BlitSurface(image, imgrect, screen, dstrect) == -2 ) {
  1393 		while ( SDL_LockSurface(image) < 0 )
  1394 			Sleep(10);
  1395 		-- Write image pixels to image->pixels --
  1396 		SDL_UnlockSurface(image);
  1397 	}
  1398  * This happens under DirectX 5.0 when the system switches away from your
  1399  * fullscreen application.  The lock will also fail until you have access
  1400  * to the video memory again.
  1401  */
  1402 /* You should call SDL_BlitSurface() unless you know exactly how SDL
  1403    blitting works internally and how to use the other blit functions.
  1404 */
  1405 #define SDL_BlitSurface SDL_UpperBlit
  1406 
  1407 /* This is the public blit function, SDL_BlitSurface(), and it performs
  1408    rectangle validation and clipping before passing it to SDL_LowerBlit()
  1409 */
  1410 extern DECLSPEC int SDLCALL SDL_UpperBlit
  1411     (SDL_Surface * src, SDL_Rect * srcrect,
  1412      SDL_Surface * dst, SDL_Rect * dstrect);
  1413 /* This is a semi-private blit function and it performs low-level surface
  1414    blitting only.
  1415 */
  1416 extern DECLSPEC int SDLCALL SDL_LowerBlit
  1417     (SDL_Surface * src, SDL_Rect * srcrect,
  1418      SDL_Surface * dst, SDL_Rect * dstrect);
  1419 
  1420 /**
  1421  * \fn int SDL_SoftStretch(SDL_Surface * src, SDL_Rect * srcrect, SDL_Surface * dst, SDL_Rect * dstrect)
  1422  *
  1423  * \brief Perform a fast, low quality, stretch blit between two surfaces of the same pixel format.
  1424  *
  1425  * \note This function uses a static buffer, and is not thread-safe.
  1426  */
  1427 extern DECLSPEC int SDLCALL SDL_SoftStretch(SDL_Surface * src,
  1428                                             SDL_Rect * srcrect,
  1429                                             SDL_Surface * dst,
  1430                                             SDL_Rect * dstrect);
  1431 
  1432 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
  1433 /* OpenGL support functions.                                                 */
  1434 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
  1435 
  1436 /**
  1437  * \fn int SDL_GL_LoadLibrary(const char *path)
  1438  *
  1439  * \brief Dynamically load an OpenGL library.
  1440  *
  1441  * \param path The platform dependent OpenGL library name, or NULL to open the default OpenGL library
  1442  *
  1443  * \return 0 on success, or -1 if the library couldn't be loaded
  1444  *
  1445  * \note If you do this, you need to retrieve all of the GL functions used in
  1446  *       your program from the dynamic library using SDL_GL_GetProcAddress().
  1447  *
  1448  * \sa SDL_GL_GetProcAddress()
  1449  */
  1450 extern DECLSPEC int SDLCALL SDL_GL_LoadLibrary(const char *path);
  1451 
  1452 /**
  1453  * \fn void *SDL_GL_GetProcAddress(const char *proc)
  1454  *
  1455  * \brief Get the address of an OpenGL function.
  1456  */
  1457 extern DECLSPEC void *SDLCALL SDL_GL_GetProcAddress(const char *proc);
  1458 
  1459 /**
  1460  * \fn int SDL_GL_SetAttribute(SDL_GLattr attr, int value)
  1461  *
  1462  * \brief Set an OpenGL window attribute before window creation.
  1463  */
  1464 extern DECLSPEC int SDLCALL SDL_GL_SetAttribute(SDL_GLattr attr, int value);
  1465 
  1466 /**
  1467  * \fn int SDL_GL_GetWindowAttribute(SDL_WindowID windowID, SDL_GLattr attr, int *value)
  1468  *
  1469  * \brief Get the actual value for an OpenGL window attribute.
  1470  */
  1471 extern DECLSPEC int SDLCALL SDL_GL_GetWindowAttribute(SDL_WindowID windowID,
  1472                                                       SDL_GLattr attr,
  1473                                                       int *value);
  1474 
  1475 /**
  1476  * \fn SDL_GLContext SDL_GL_CreateContext(SDL_WindowID windowID)
  1477  *
  1478  * \brief Create an OpenGL context for use with an OpenGL window, and make it current.
  1479  *
  1480  * \sa SDL_GL_DeleteContext()
  1481  */
  1482 extern DECLSPEC SDL_GLContext SDLCALL SDL_GL_CreateContext(SDL_WindowID
  1483                                                            windowID);
  1484 
  1485 /**
  1486  * \fn int SDL_GL_MakeCurrent(SDL_WindowID windowID, SDL_GLContext context)
  1487  *
  1488  * \brief Set up an OpenGL context for rendering into an OpenGL window.
  1489  *
  1490  * \note The context must have been created with a compatible window.
  1491  */
  1492 extern DECLSPEC int SDLCALL SDL_GL_MakeCurrent(SDL_WindowID windowID,
  1493                                                SDL_GLContext context);
  1494 
  1495 /**
  1496  * \fn int SDL_GL_SetSwapInterval(int interval)
  1497  *
  1498  * \brief Set the swap interval for the current OpenGL context.
  1499  *
  1500  * \sa SDL_GL_GetSwapInterval()
  1501  */
  1502 extern DECLSPEC int SDLCALL SDL_GL_SetSwapInterval(int interval);
  1503 
  1504 /**
  1505  * \fn int SDL_GL_GetSwapInterval(void)
  1506  *
  1507  * \brief Get the swap interval for the current OpenGL context.
  1508  *
  1509  * \sa SDL_GL_SetSwapInterval()
  1510  */
  1511 extern DECLSPEC int SDLCALL SDL_GL_GetSwapInterval(void);
  1512 
  1513 /**
  1514  * \fn void SDL_GL_SwapBuffers(void)
  1515  *
  1516  * Swap the OpenGL buffers, if double-buffering is supported.
  1517  */
  1518 extern DECLSPEC void SDLCALL SDL_GL_SwapBuffers(void);
  1519 
  1520 /**
  1521  * \fn void SDL_GL_DeleteContext(SDL_GLContext context)
  1522  *
  1523  * \brief Delete an OpenGL context.
  1524  *
  1525  * \sa SDL_GL_CreateContext()
  1526  */
  1527 extern DECLSPEC void SDLCALL SDL_GL_DeleteContext(SDL_GLContext context);
  1528 
  1529 /**
  1530  * \def SDL_RectEmpty()
  1531  *
  1532  * \brief Returns true if the rectangle has no area.
  1533  */
  1534 #define SDL_RectEmpty(X)    (((X)->w <= 0) || ((X)->h <= 0))
  1535 
  1536 /**
  1537  * \def SDL_RectEquals()
  1538  *
  1539  * \brief Returns true if the two rectangles are equal.
  1540  */
  1541 #define SDL_RectEquals(A, B)   (((A)->x == (B)->x) && ((A)->y == (B)->y) && \
  1542                                 ((A)->w == (B)->w) && ((A)->h == (B)->h))
  1543 
  1544 /**
  1545  * \fn SDL_bool SDL_HasIntersection(const SDL_Rect * A, const SDL_Rect * B);
  1546  *
  1547  * \brief Determine whether two rectangles intersect.
  1548  *
  1549  * \return SDL_TRUE if there is an intersection, SDL_FALSE otherwise.
  1550  */
  1551 extern DECLSPEC SDL_bool SDLCALL SDL_HasIntersection(const SDL_Rect * A,
  1552                                                      const SDL_Rect * B);
  1553 
  1554 /**
  1555  * \fn SDL_bool SDL_IntersectRect(const SDL_Rect * A, const SDL_Rect * B, SDL_Rect * result)
  1556  *
  1557  * \brief Calculate the intersection of two rectangles.
  1558  *
  1559  * \return SDL_TRUE if there is an intersection, SDL_FALSE otherwise.
  1560  */
  1561 extern DECLSPEC SDL_bool SDLCALL SDL_IntersectRect(const SDL_Rect * A,
  1562                                                    const SDL_Rect * B,
  1563                                                    SDL_Rect * result);
  1564 
  1565 /**
  1566  * \fn void SDL_UnionRect(const SDL_Rect * A, const SDL_Rect * B, SDL_Rect * result)
  1567  *
  1568  * \brief Calculate the union of two rectangles
  1569  */
  1570 extern DECLSPEC void SDLCALL SDL_UnionRect(const SDL_Rect * A,
  1571                                            const SDL_Rect * B,
  1572                                            SDL_Rect * result);
  1573 
  1574 /* Ends C function definitions when using C++ */
  1575 #ifdef __cplusplus
  1576 /* *INDENT-OFF* */
  1577 }
  1578 /* *INDENT-ON* */
  1579 #endif
  1580 #include "close_code.h"
  1581 
  1582 #endif /* _SDL_video_h */
  1583 
  1584 /* vi: set ts=4 sw=4 expandtab: */